subject:(cyclic peptides)

University of Aberdeen

1. Umeobika, Ugochukwu Christian. Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues.

Degree: PhD, 2017, University of Aberdeen

URL: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153069850005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.725376

► Ribosomal synthesized and post translational modified peptide natural products have attracted a lot of interest in the past decade. Backbone cyclization of the translated linear… (more)

Subjects/Keywords: 547; Cyclic peptides; Peptides

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Umeobika, U. C. (2017). Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues. (Doctoral Dissertation). University of Aberdeen. Retrieved from https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153069850005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.725376

Chicago Manual of Style (16^th Edition):

Umeobika, Ugochukwu Christian. “Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues.” 2017. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153069850005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.725376.

MLA Handbook (7^th Edition):

Umeobika, Ugochukwu Christian. “Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues.” 2017. Web. 23 Jan 2021.

Vancouver:

Umeobika UC. Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues. [Internet] [Doctoral dissertation]. University of Aberdeen; 2017. [cited 2021 Jan 23]. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153069850005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.725376.

Council of Science Editors:

Umeobika UC. Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues. [Doctoral Dissertation]. University of Aberdeen; 2017. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153069850005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.725376

University of Aberdeen

2. Adaba, Rosemary Isioma. Chemical characterization and quantification of enzymatically synthesised cyclic peptides.

Degree: PhD, 2017, University of Aberdeen

URL: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153095890005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723247

► This thesis presents results for the extraction, purification and chemical characterisation and quantification of cyclic peptides. The thesis is divided into six chapters including a… (more)

Subjects/Keywords: 547; Cyclic peptides

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Adaba, R. I. (2017). Chemical characterization and quantification of enzymatically synthesised cyclic peptides. (Doctoral Dissertation). University of Aberdeen. Retrieved from https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153095890005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723247

Chicago Manual of Style (16^th Edition):

Adaba, Rosemary Isioma. “Chemical characterization and quantification of enzymatically synthesised cyclic peptides.” 2017. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153095890005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723247.

MLA Handbook (7^th Edition):

Adaba, Rosemary Isioma. “Chemical characterization and quantification of enzymatically synthesised cyclic peptides.” 2017. Web. 23 Jan 2021.

Vancouver:

Adaba RI. Chemical characterization and quantification of enzymatically synthesised cyclic peptides. [Internet] [Doctoral dissertation]. University of Aberdeen; 2017. [cited 2021 Jan 23]. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153095890005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723247.

Council of Science Editors:

Adaba RI. Chemical characterization and quantification of enzymatically synthesised cyclic peptides. [Doctoral Dissertation]. University of Aberdeen; 2017. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12153095890005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723247

University of Aberdeen

3. Rickaby, Kirstie. Investigation of the chemo-enzymatic synthesis of cyclic peptides.

Degree: PhD, 2018, University of Aberdeen

URL: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152299330005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.759981

► Cyclic peptides constitute an attractive class of compounds for drug development, however the numerous problems associated with their synthesis have limited their applicability. The cyclisation… (more)

▼ Cyclic peptides constitute an attractive class of compounds for drug development, however the numerous problems associated with their synthesis have limited their applicability. The cyclisation step itself is particularly problematic, with solution phase cyclisations being required to be conducted under very high dilution to promote cyclisation over unwanted side reactions such as oligomerisation. In addition, epimerisation, leading to the loss of chiral integrity at the terminal residues is a major concern. Attention is now turning to biochemical cyclisation strategies, such as SICLOPPS and sortase mediated ligation, although these also come with their own inherent disadvantages, for example, in the case of sortase mediated ligation, there is significant “scarring” of the target due to the presence of a four amino acid long recognition sequence. Cyclisation using ribosomally synthesised post translationally modified enzymes is also gaining popularity. One such family of enzymes is the patellamides. PatGmac is capable of performing cyclisations on linear peptide substrates with minimal scarring compared to the aforementioned alternatives and, importantly, with no epimerisation and could constitute a greener and more facile route to cyclic peptides. The work herein details some of the investigations designed to define the range of synthetic utility and test the flexibility of the enzymes. This was done qualitatively, by designing a variety of linear peptide analogues of the natural product, homophymine A, featuring unique structural moieties and evaluating their compatibility with the enzyme. It was also done quantitatively, using an LCMS based semi-quantitative strategy, to assess differences between similar, but different, enzymes and to assess whether there were differences in how different substrates are processed by the same enzyme. In addition to this, a variety of these substrates were also assessed for their proclivity to cyclise under standard chemical conditions for comparison. Lastly, with the increasing appearance cyclic peptides and non-peptidic macrocycles in the libraries of compounds being considered for clinical trials, there is now a growing need for computational modelling of these structures. Herein, a 3D v structure for the natural product callipetin N is proposed for the first time, determined using a combination of computational and NMR techniques.

Subjects/Keywords: 540; Cyclic peptides; Enzymes

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rickaby, K. (2018). Investigation of the chemo-enzymatic synthesis of cyclic peptides. (Doctoral Dissertation). University of Aberdeen. Retrieved from https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152299330005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.759981

Chicago Manual of Style (16^th Edition):

Rickaby, Kirstie. “Investigation of the chemo-enzymatic synthesis of cyclic peptides.” 2018. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152299330005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.759981.

MLA Handbook (7^th Edition):

Rickaby, Kirstie. “Investigation of the chemo-enzymatic synthesis of cyclic peptides.” 2018. Web. 23 Jan 2021.

Vancouver:

Rickaby K. Investigation of the chemo-enzymatic synthesis of cyclic peptides. [Internet] [Doctoral dissertation]. University of Aberdeen; 2018. [cited 2021 Jan 23]. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152299330005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.759981.

Council of Science Editors:

Rickaby K. Investigation of the chemo-enzymatic synthesis of cyclic peptides. [Doctoral Dissertation]. University of Aberdeen; 2018. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152299330005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.759981

University of Aberdeen

4. Adaba, Rosemary Isioma. Chemical characterization and quantification of enzymatically synthesised cyclic peptides.

Degree: Dept. of Chemistry., 2017, University of Aberdeen

URL: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233135 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233135&custom_att_2=simple_viewer

Subjects/Keywords: Cyclic peptides

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Adaba, R. I. (2017). Chemical characterization and quantification of enzymatically synthesised cyclic peptides. (Doctoral Dissertation). University of Aberdeen. Retrieved from http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233135 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233135&custom_att_2=simple_viewer

Chicago Manual of Style (16^th Edition):

Adaba, Rosemary Isioma. “Chemical characterization and quantification of enzymatically synthesised cyclic peptides.” 2017. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233135 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233135&custom_att_2=simple_viewer.

MLA Handbook (7^th Edition):

Adaba, Rosemary Isioma. “Chemical characterization and quantification of enzymatically synthesised cyclic peptides.” 2017. Web. 23 Jan 2021.

Vancouver:

Adaba RI. Chemical characterization and quantification of enzymatically synthesised cyclic peptides. [Internet] [Doctoral dissertation]. University of Aberdeen; 2017. [cited 2021 Jan 23]. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233135 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233135&custom_att_2=simple_viewer.

Council of Science Editors:

Adaba RI. Chemical characterization and quantification of enzymatically synthesised cyclic peptides. [Doctoral Dissertation]. University of Aberdeen; 2017. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233135 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233135&custom_att_2=simple_viewer

University of Aberdeen

5. Umeobika, Ugochukwu Christian.; University of Aberdeen.Dept. of Chemistry. Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues.

Degree: Dept. of Chemistry., 2017, University of Aberdeen

URL: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233678 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233678&custom_att_2=simple_viewer

Subjects/Keywords: Cyclic peptides.; Peptides.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Umeobika, U. C. ;. U. o. A. D. o. C. (2017). Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues. (Doctoral Dissertation). University of Aberdeen. Retrieved from http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233678 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233678&custom_att_2=simple_viewer

Chicago Manual of Style (16^th Edition):

Umeobika, Ugochukwu Christian ; University of Aberdeen Dept of Chemistry. “Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues.” 2017. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233678 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233678&custom_att_2=simple_viewer.

MLA Handbook (7^th Edition):

Umeobika, Ugochukwu Christian ; University of Aberdeen Dept of Chemistry. “Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues.” 2017. Web. 23 Jan 2021.

Vancouver:

Umeobika UC;UoADoC. Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues. [Internet] [Doctoral dissertation]. University of Aberdeen; 2017. [cited 2021 Jan 23]. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233678 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233678&custom_att_2=simple_viewer.

Council of Science Editors:

Umeobika UC;UoADoC. Solid phase peptide synthesis of substrates for the chemoenzymatic generation of cyanobactins analogues. [Doctoral Dissertation]. University of Aberdeen; 2017. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=233678 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=233678&custom_att_2=simple_viewer

Boston College

6. Condurso, Heather Lindsay. Structural and Functional Investigations into the Biosynthesis of Peptide Natural Products.

Degree: PhD, Chemistry, 2013, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:104069

► Peptide natural products have diverse, elaborate scaffolds and are important leads in the development of new drugs. A complete understanding of the natural biosynthetic pathways… (more)

▼ Peptide natural products have diverse, elaborate scaffolds and are important leads in the development of new drugs. A complete understanding of the natural biosynthetic pathways of these compounds can improve chemical syntheses and boost bioengineering efforts. There are two classes of peptide natural products: ribosomal and nonribosomal peptides. Ribosomally produced and posttranslationally modified peptides (RiPPs) are produced by the ribosome using the 20 canonical amino acids and undergo extensive tailoring to yield the active natural products. Nonribosomal peptides (NRPs) are assembled through an enzyme dependent system and can incorporate over 500 different amino and acyl building blocks to impart complexity. These peptides can also undergo additional tailoring to further modify the core peptide. The microviridins are a class of RiPPs that are modified by two ATP dependent ligases to create a total of three macrocyclic bonds. We have solved the three dimensional protein structures of each of these ligases to establish the mechanism of substrate recognition and cyclization. Vancomycin is a NRP that contains five nonproteinogenic aromatic amino acids that are necessary for biological activity. One of these amino acids is derived from a polyketide pathway and undergoes a four-electron oxidation by a cofactor independent dioxygenase, DpgC. We have solved the structure of this enzyme and have established a radical mechanism. We have investigated this mechanism using synthetic probes and mutagenesis. We have examined O₂ binding using molecular dynamics and mutagenesis. NRPs are synthesized by the multidomain, modular nonribosomal peptide synthetases (NRPSs) in an enzyme templated, ATP-dependent manner. We have synthesized domain specific probes to study the structures and mechanisms of these pathways. Our continued work will provide the insight necessary to manipulate these pathways to provide biologically active compounds. Advisors/Committee Members: Marc Snapper (Thesis advisor), Steven Bruner (Thesis advisor).

Subjects/Keywords: cyclic peptides; microviridin; natural products; nonribosomal peptides; ribosomal peptides

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Condurso, H. L. (2013). Structural and Functional Investigations into the Biosynthesis of Peptide Natural Products. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:104069

Chicago Manual of Style (16^th Edition):

Condurso, Heather Lindsay. “Structural and Functional Investigations into the Biosynthesis of Peptide Natural Products.” 2013. Doctoral Dissertation, Boston College. Accessed January 23, 2021. http://dlib.bc.edu/islandora/object/bc-ir:104069.

MLA Handbook (7^th Edition):

Condurso, Heather Lindsay. “Structural and Functional Investigations into the Biosynthesis of Peptide Natural Products.” 2013. Web. 23 Jan 2021.

Vancouver:

Condurso HL. Structural and Functional Investigations into the Biosynthesis of Peptide Natural Products. [Internet] [Doctoral dissertation]. Boston College; 2013. [cited 2021 Jan 23]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:104069.

Council of Science Editors:

Condurso HL. Structural and Functional Investigations into the Biosynthesis of Peptide Natural Products. [Doctoral Dissertation]. Boston College; 2013. Available from: http://dlib.bc.edu/islandora/object/bc-ir:104069

Seton Hall University

7. Elashal, Hader E. Cyclic Urethane: A Versatile Handle for Synthetic Peptide Applications.

Degree: PhD, Chemistry and Biochemistry, 2018, Seton Hall University

URL: https://scholarship.shu.edu/dissertations/2530

► While peptides have impeccable potential due to their biological and therapeutic abilities, they are inherently limited in clinical practice due to their instability towards… (more)

▼ While peptides have impeccable potential due to their biological and therapeutic abilities, they are inherently limited in clinical practice due to their instability towards proteolysis and poor bioavailability. In the past few years peptidomimetics have emerged as a powerful class of compounds that overcomes the shortcomings associated with peptides. Peptidomimetics essentially mimic a natural peptide or protein in its chemical composition, structure and its ability to perform a biologically relevant role. In addition to increased stability and bioavailability, peptidomimetics can also have increased receptor binding affinity and selectivity, thereby making these mimics lead compounds in the field of drug design and discovery. Most recently, modifications to the peptide backbone have been introduced to increase the versatility of peptidomimetic applications. This thesis work is based on the unrestricted ability to modify amino acid side chain residues within biologically relevant peptides and form new classes of peptidomimetics for studying their structure-function properties. Motivated by the idea of introducing a multipurpose moiety to increase the functionality of peptides, we sought to incorporate the cyclic urethane moiety otherwise known as 2-oxazolidinone and to explore the plethora of applications that accompany this incorporation. In the process of designing cyclic urethane containing peptides, we sought to peruse an approach where the cyclic urethane moiety would be derived from naturally occurring amino acids serine, threonine, glutamic acid, and/or cysteine. Modification of serine’s hydroxymethyl side chain to a 2- oxazolidinone moiety activates the peptide backbone chain and increases its susceptibility towards cleavage. Due to the versatility of this moiety, 2-oxazolidinone has been used to explore various applications such as protease mimics, formation of peptide thioesters, and modified C-terminal peptides. When used as a protease mimic, formation of 2-oxazolidinone allows for site-selective cleavage of extremely unreactive peptide bonds using neutral aqueous conditions. This method exhibits broad substrate scope and selectively cleaves various bioactive peptides with post-translational modifications (e.g. N-acetylation and N-methylation) and mutations (D- and β-amino acids), which are unsuitable substrates for enzymes. Further application of this method has been demonstrated by the sequencing of cyclic peptides which is difficult to achieve by utilizing traditional methods such as Edman’s degradation and MS/MS. Identifying the sequence of macrocyclic peptides is vital in exploring potential therapeutic candidates found in nature and/or created through split and pool techniques. Building on the susceptibility of 2-oxazolidinone to cleavage, this moiety was also utilized for the formation of peptide thioesters, which is of significance in native chemical ligation for the synthesis of large proteins. This approach allows the synthesis of peptide thioesters by using Fmoc SPPS, which is… Advisors/Committee Members: Monika Raj, Ph.D., Cecilia Marzabadi, Ph.D..

Subjects/Keywords: peptides; lasso peptides; peptidomimetics; cyclic peptides; sequencing; thioesters; Biochemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Elashal, H. E. (2018). Cyclic Urethane: A Versatile Handle for Synthetic Peptide Applications. (Doctoral Dissertation). Seton Hall University. Retrieved from https://scholarship.shu.edu/dissertations/2530

Chicago Manual of Style (16^th Edition):

Elashal, Hader E. “Cyclic Urethane: A Versatile Handle for Synthetic Peptide Applications.” 2018. Doctoral Dissertation, Seton Hall University. Accessed January 23, 2021. https://scholarship.shu.edu/dissertations/2530.

MLA Handbook (7^th Edition):

Elashal, Hader E. “Cyclic Urethane: A Versatile Handle for Synthetic Peptide Applications.” 2018. Web. 23 Jan 2021.

Vancouver:

Elashal HE. Cyclic Urethane: A Versatile Handle for Synthetic Peptide Applications. [Internet] [Doctoral dissertation]. Seton Hall University; 2018. [cited 2021 Jan 23]. Available from: https://scholarship.shu.edu/dissertations/2530.

Council of Science Editors:

Elashal HE. Cyclic Urethane: A Versatile Handle for Synthetic Peptide Applications. [Doctoral Dissertation]. Seton Hall University; 2018. Available from: https://scholarship.shu.edu/dissertations/2530

Nelson Mandela Metropolitan University

8. Qhola, Lipolelo. The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO).

Degree: Faculty of Health Sciences, 2012, Nelson Mandela Metropolitan University

URL: http://hdl.handle.net/10948/d1011619

► Cyclic dipeptides have been widely used as pharmaceutical agents due to their favourable properties and the fact that they are more stable and membrane permeable… (more)

Subjects/Keywords: Cyclic peptides; Pharmaceutical chemistry; Peptide drugs

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APA (6^th Edition):

Qhola, L. (2012). The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO). (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/d1011619

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Qhola, Lipolelo. “The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO).” 2012. Thesis, Nelson Mandela Metropolitan University. Accessed January 23, 2021. http://hdl.handle.net/10948/d1011619.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Qhola, Lipolelo. “The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO).” 2012. Web. 23 Jan 2021.

Vancouver:

Qhola L. The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO). [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2012. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10948/d1011619.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Qhola L. The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO). [Thesis]. Nelson Mandela Metropolitan University; 2012. Available from: http://hdl.handle.net/10948/d1011619

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nelson Mandela Metropolitan University

9. Milne, Marnus. The medicinal chemistry of cyclo(Phe-4CI-Pro) and Cyclo(D-Phe-4CI-Pro).

Degree: Faculty of Health Sciences, 2012, Nelson Mandela Metropolitan University

URL: http://hdl.handle.net/10948/d1011848

► Cyclic dipeptides have limited conformational freedom due to their diketopiperazine backbone and their small size. They are relatively simple to synthesise, making them ideal subjects… (more)

▼ Cyclic dipeptides have limited conformational freedom due to their diketopiperazine backbone and their small size. They are relatively simple to synthesise, making them ideal subjects for investigation into their biological effects. Cyclic dipeptides have also been known for their multitude of biological activities, including antimicrobial, anticancer and haematological properties. In this study the cyclic dipeptides, cyclo(Phe-4Cl-Pro) and cyclo(D-Phe-4Cl-Pro), were synthesised from their corresponding linear precursors using a modified phenol-induced cyclisation procedure. The phenol induced cyclisation procedure resulted in good yields and purity of the cyclic dipeptides. Quantitative analysis and evaluation of the physiochemical properties of the cyclic dipeptides was achieved using high-performance liquid chromatography, scanning electron microscopy, thermal analysis and X-ray powder diffraction. Structural elucidation of the cyclic dipeptides was done by means of infrared spectroscopy, mass spectroscopy, nuclear magnetic resonance spectroscopy and molecular modelling. The study‟s aim was to determine the biological activity of cyclo(Phe-4Cl-Pro) and cyclo(D-Phe-4Cl-Pro) with respect to their anticancer, antimicrobial, haematological and ant-diabetic studies. Anticancer studies revealed that cyclo(Phe-4Cl-Pro) and cyclo(D-Phe-4Cl-Pro) inhibited the growth of HeLa (cervical cancer), HT-29 (colon cancer) and MCF-7 (breast cancer) cancer cell lines. Both cyclic dipeptides also inhibited the growth of certain selected Gram-positive, Gram-negative and fungal microorganisms in the antimicrobial study. Although the inhibition of growth in the anticancer and antimicrobial studies was statistically significant, the clinical relevance is questionable, since the inhibition produced by both cyclic dipeptides was very limited compared to other pre-existing anticancer and antimicrobial agents. Both cyclic dipeptides caused a significant shortening of the APTT and PT clotting times and an increase in the fibrin and D-Dimer formation. Cyclo(D-Phe-4Cl-Pro) at a screening concentration of 12.5 mM and 3.125 mM, showed significant anti-platelet activity. Both cyclic dipeptides failed to produce any inhibition of the α-Glucosidase enzyme and very limited inhibition of the α-Amylase enzyme. Advisors/Committee Members: Dealtry, G Dr, Killian, G Dr.

Subjects/Keywords: Cyclic peptides; Pharmaceutical chemistry; Peptide drugs

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Milne, M. (2012). The medicinal chemistry of cyclo(Phe-4CI-Pro) and Cyclo(D-Phe-4CI-Pro). (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/d1011848

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Milne, Marnus. “The medicinal chemistry of cyclo(Phe-4CI-Pro) and Cyclo(D-Phe-4CI-Pro).” 2012. Thesis, Nelson Mandela Metropolitan University. Accessed January 23, 2021. http://hdl.handle.net/10948/d1011848.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Milne, Marnus. “The medicinal chemistry of cyclo(Phe-4CI-Pro) and Cyclo(D-Phe-4CI-Pro).” 2012. Web. 23 Jan 2021.

Vancouver:

Milne M. The medicinal chemistry of cyclo(Phe-4CI-Pro) and Cyclo(D-Phe-4CI-Pro). [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2012. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10948/d1011848.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Milne M. The medicinal chemistry of cyclo(Phe-4CI-Pro) and Cyclo(D-Phe-4CI-Pro). [Thesis]. Nelson Mandela Metropolitan University; 2012. Available from: http://hdl.handle.net/10948/d1011848

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

10. Milne, Mark Andrew. Synthesis and Characterization of New Cyclic and Acylic Ferrocene Peptide Conjugates.

Degree: 2009, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-03132009-160141

► In this thesis a series of diphenol phenanthroline (Dpp) peptide conjugates were synthesized and then coupled to ferrocene to give the corresponding organometallic conjugates. The… (more)

Subjects/Keywords: Cyclic; Peptides; Ferrocene

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APA (6^th Edition):

Milne, M. A. (2009). Synthesis and Characterization of New Cyclic and Acylic Ferrocene Peptide Conjugates. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-03132009-160141

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Milne, Mark Andrew. “Synthesis and Characterization of New Cyclic and Acylic Ferrocene Peptide Conjugates.” 2009. Thesis, University of Saskatchewan. Accessed January 23, 2021. http://hdl.handle.net/10388/etd-03132009-160141.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Milne, Mark Andrew. “Synthesis and Characterization of New Cyclic and Acylic Ferrocene Peptide Conjugates.” 2009. Web. 23 Jan 2021.

Vancouver:

Milne MA. Synthesis and Characterization of New Cyclic and Acylic Ferrocene Peptide Conjugates. [Internet] [Thesis]. University of Saskatchewan; 2009. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10388/etd-03132009-160141.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Milne MA. Synthesis and Characterization of New Cyclic and Acylic Ferrocene Peptide Conjugates. [Thesis]. University of Saskatchewan; 2009. Available from: http://hdl.handle.net/10388/etd-03132009-160141

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Aberdeen

11. Rickaby, Kirstie.; Trembleau, Laurent.; Houssen, Wael.; Jaspers, Marcel.; AstraZeneca (Firm); University of Aberdeen. Investigation of the chemo-enzymatic synthesis of cyclic peptides.

Degree: 2018, University of Aberdeen

URL: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=238613 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=238613&custom_att_2=simple_viewer

Subjects/Keywords: Cyclic peptides; Enzymes

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APA (6^th Edition):

Rickaby, Kirstie.; Trembleau, Laurent.; Houssen, Wael.; Jaspers, M. ;. A. (. U. o. A. (2018). Investigation of the chemo-enzymatic synthesis of cyclic peptides. (Doctoral Dissertation). University of Aberdeen. Retrieved from http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=238613 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=238613&custom_att_2=simple_viewer

Chicago Manual of Style (16^th Edition):

Rickaby, Kirstie.; Trembleau, Laurent.; Houssen, Wael.; Jaspers, Marcel ; AstraZeneca (Firm); University of Aberdeen. “Investigation of the chemo-enzymatic synthesis of cyclic peptides.” 2018. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=238613 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=238613&custom_att_2=simple_viewer.

MLA Handbook (7^th Edition):

Rickaby, Kirstie.; Trembleau, Laurent.; Houssen, Wael.; Jaspers, Marcel ; AstraZeneca (Firm); University of Aberdeen. “Investigation of the chemo-enzymatic synthesis of cyclic peptides.” 2018. Web. 23 Jan 2021.

Vancouver:

Rickaby, Kirstie.; Trembleau, Laurent.; Houssen, Wael.; Jaspers M;A(UoA. Investigation of the chemo-enzymatic synthesis of cyclic peptides. [Internet] [Doctoral dissertation]. University of Aberdeen; 2018. [cited 2021 Jan 23]. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=238613 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=238613&custom_att_2=simple_viewer.

Council of Science Editors:

Rickaby, Kirstie.; Trembleau, Laurent.; Houssen, Wael.; Jaspers M;A(UoA. Investigation of the chemo-enzymatic synthesis of cyclic peptides. [Doctoral Dissertation]. University of Aberdeen; 2018. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=238613 ; http://digitool.abdn.ac.uk:1801/webclient/DeliveryManager?pid=238613&custom_att_2=simple_viewer

University of Sydney

12. Tran, Daniel Hao. Design, Synthesis and Evaluation of Cyclic Peptide Bromodomain Inhibitors .

Degree: University of Sydney

URL: http://hdl.handle.net/2123/22717

► The acetylation of lysine residues is a post-translational modification that plays an important role in cellular signalling and disease biology. The enzymes responsible for the… (more)

▼ The acetylation of lysine residues is a post-translational modification that plays an important role in cellular signalling and disease biology. The enzymes responsible for the acetylation and deacetylation of lysine, known as histone acetyltransferases (HATs) and histone deacetylases (HDACs), are exciting targets in current drug development research. However, very few potent and/or selective inhibitors of these enzymes have been developed to date. Bromodomains (BRDs) are a diverse family of conserved protein-interaction modules that are responsible for identifying and binding to N-acetylated lysine residues. Numerous oncogenic proteins rely on the use of BRDs for their recruitment of specific regulatory complexes that facilitate cancerous cell growth and survival and, as such, inhibition of BRDs is now an established method for reducing cancer cell proliferation. The conserved BRD pocket contains a deep and conserved hydrophobic acetyl lysine binding site, which represents an attractive therapeutic target for the development of novel pharmaceutically active molecules. Using the RaPID mRNA display technology developed by Suga and co-workers, a small library of cyclic peptides with nanomolar binding affinities for a range of BRDs were identified. This thesis discusses the development and biological evaluation of cyclic peptides based on the results of the mRNA display, with the intention of developing a novel class of compounds designed to inhibit BRDs. In Chapter 2, the chemical synthesis of the cyclic peptides identified by the RaPID mRNA display technology is discussed. The binding activity of the molecules to BRDs was determined by surface plasmon resonance (SPR), and crystal structures of these molecules bound to bromodomains of interest have been determined and discussed. Chapter 3 addresses the structure-activity relationship (SAR) studies performed on two of the cyclic peptides from Chapter 2, discussing the rational design and binding evaluation of the analogues mentioned. The data in this thesis lays the foundation for the development of novel cancer therapeutics that target BRDs.

Subjects/Keywords: bromodomains; cyclic peptides

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APA (6^th Edition):

Tran, D. H. (n.d.). Design, Synthesis and Evaluation of Cyclic Peptide Bromodomain Inhibitors . (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/22717

Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tran, Daniel Hao. “Design, Synthesis and Evaluation of Cyclic Peptide Bromodomain Inhibitors .” Thesis, University of Sydney. Accessed January 23, 2021. http://hdl.handle.net/2123/22717.

Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tran, Daniel Hao. “Design, Synthesis and Evaluation of Cyclic Peptide Bromodomain Inhibitors .” Web. 23 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Tran DH. Design, Synthesis and Evaluation of Cyclic Peptide Bromodomain Inhibitors . [Internet] [Thesis]. University of Sydney; [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2123/22717.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.

Council of Science Editors:

Tran DH. Design, Synthesis and Evaluation of Cyclic Peptide Bromodomain Inhibitors . [Thesis]. University of Sydney; Available from: http://hdl.handle.net/2123/22717

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.

Nelson Mandela Metropolitan University

13. Ndung'u, Susan Wanjiru. The medicinal chemistry of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro).

Degree: Faculty of Health Sciences, 2011, Nelson Mandela Metropolitan University

URL: http://hdl.handle.net/10948/7083

► Although peptides and proteins are considered as lead compounds for the discovery and development of new therapeutic agents, poor metabolic and physical properties have limited… (more)

▼ Although peptides and proteins are considered as lead compounds for the discovery and development of new therapeutic agents, poor metabolic and physical properties have limited their optimisation as drug candidates (Adessi & Soto, 2002). Research by medicinal chemists however, generated the discovery of structural similarities between some peptides and diketopiperazines and the common occurrence of such compounds in natural products. This discovery initiated the synthesis of diketopiperazines from amino acids in an attempt to bypass the previously mentioned limitations of using peptides as drug candidates (Dinsmore & Beshore, 2002). Diketopiperazines (DKPs) are the simplest form of cyclic dipeptides, and a class of unexplored bioactive peptides that have great potential for the future. The compounds are relatively simple to synthesise and are prevalent in nature (Prasad, 1995). The DKP backbone is rigid and therefore poses conformational constraint on the compounds. This rigidity allows for simple conformational analysis of the compounds and also gives insight into the conformational requirements for interaction with the targets involved in their biological activity. The reduced conformational freedom also increases the receptor specificity and thus the compounds are proposed to have less unfavourable effects (Anteunis, 1978). The aim of the study was to synthesise compounds that would exhibit metabolic stability, receptor specificity and enhanced lipophilicity which would increase the bioavailability of the compounds. This was to be achieved by the introduction of fluorine and chlorine elements into the DKPs. The structure of the DKPs would be altered which in turn would improve the physicochemical properties and the biological activity of the compounds (Naumann, 1999). Cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro) were synthesised using the method of Milne et al. (1992) and by boiling the linear counterparts under reflux in sec-butanol-toluene. The structures of the synthesised DKPs were elucidated using mass spectrometry, nuclear magnetic resonance spectroscopy, infrared spectroscopy and molecular modeling. Qualitative analysis and evaluation of the physicochemical properties of the DKPs were performed using high-performance liquid chromatography, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and x-ray powder diffraction. The study aimed to determine the biological activity of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro) with respect to their anticancer, antimicrobial, haematological and antidiabetic effects. The anticancer results obtained indicated that the percentage inhibition produced by both DKPs were lower than those proposed by Graz et al. (2000) for proline-containing DKPs where, a greater than 50% inhibition was observed for cyclo(Phe-Pro). Antimicrobial studies revealed that both DKPs demonstrated marginal effects on Gram-positive and Gram-negative organisms but showed significant effects against C. albicans. The haematological studies revealed that…

Subjects/Keywords: Peptide drugs; Cyclic peptides; Pharmaceutical chemistry; Peptides – Synthesis

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APA (6^th Edition):

Ndung'u, S. W. (2011). The medicinal chemistry of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro). (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/7083

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ndung'u, Susan Wanjiru. “The medicinal chemistry of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro).” 2011. Thesis, Nelson Mandela Metropolitan University. Accessed January 23, 2021. http://hdl.handle.net/10948/7083.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ndung'u, Susan Wanjiru. “The medicinal chemistry of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro).” 2011. Web. 23 Jan 2021.

Vancouver:

Ndung'u SW. The medicinal chemistry of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro). [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2011. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10948/7083.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ndung'u SW. The medicinal chemistry of cyclo(D-Phe-2Cl-Pro) and cyclo(Phe-4F-Pro). [Thesis]. Nelson Mandela Metropolitan University; 2011. Available from: http://hdl.handle.net/10948/7083

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Abbour, Shoukri. Pseudopeptides cycliques biocides de novo : Cyclic biocide pseudopeptides de novo.

Degree: Docteur es, Chimie, 2013, Rennes 1

URL: http://www.theses.fr/2013REN1S182

►

L'identification de nouveaux agents anti-infectieux, actifs contre les pathogènes et les micro-organismes multi-résistants, reste un enjeu majeur pour la science. Parmi les molécules développées pour… (more)

▼

L'identification de nouveaux agents anti-infectieux, actifs contre les pathogènes et les micro-organismes multi-résistants, reste un enjeu majeur pour la science. Parmi les molécules développées pour combattre ces infections, les peptides thérapeutiques apparaissent comme un champ prometteur de recherche. Ils se synthétisent rapidement, grâce à la synthèse sur support solide automatisée, et leur structure modulable facilite la découverte et l'amélioration d'activités biologiques. Le principal inconvénient des peptides est leur manque de résistance face à la dégradation protéolytique, et donc leur rapide élimination du corps humain. L'introduction d'aminoacides modifiés, comme les aza-bêta³-aminoacides, au sein de la séquence peptidique, permet de renforcer la biodisponibilité de ces peptides, et peut conduire à une augmentation de l’activité biologique et/ou de la sélectivité. Les aza-bêta3-aminoacides sont des analogues aza des bêta³-aminoacides, où le carbone portant la chaîne latérale est remplacé par un atome d'azote chiral à configuration non-fixée. Introduit au sein d'une séquence peptidique, ces monomères donnent accès à des pseudopeptides dont la biodisponibilité est augmentée, et l’activité et/ou la sélectivité peuvent être améliorée. Ce mémoire de thèse présente la synthèse et la fonctionnalisation d’aza-bêta³-aminoacides, à chaînes latérales protéinogènes ou non, en vue de leur insertion en synthèse peptidique sur support solide. Deux séries de pseudopeptides cycliques de novo ont été développées. La première série cible les vésicules d’endocytose résultant d’une infection adénovirale, et la seconde série mime la séquence RGD, ligand des intégrines alpha-nu-bêta₃, qui est une cible d’intérêt contre la néo-angiogénèse tumorale.

Discovering new anti-pathogenic agent, which are effective against new or multi-drug resistant microorganisms, is still a major challenge for science. Among all the drugs, which are currently developed to fight these infections, therapeutic peptides arise as a promising research field. Their synthesis is fast, due to automated solid phase synthesis, and their adjustable structure makes the discovery and the enhancement of biological activities easier. The main drawback of peptides is their lack of resistance against proteolytic degradation, and therefore their quick elimination from the human body. Modification of peptide sequence, by introduction of aminoacids analogues, such as aza-bêta3-aminoacids, reinforces the peptide bioavailability, and can lead to an increase of the biological activity, and/or of the selectivity. Aza-bêta3-amino acids are aza analogues of bêta3-amino acids, where the side chain is carried by a chiral nitrogen atom, with a non-fixed configuration. Their introduction in a peptide sequence affords pseudopeptides, with a better bioavailability, and with an activity/selectivity which could be increased. This report describes the synthesis of aza-bêta3-aminoacids, with proteinogenic side chains or not, in order to insert them in solid phase peptide synthesis.…

Advisors/Committee Members: Baudy-Floc'h, Michèle (thesis director).

Subjects/Keywords: Peptides cycliques; Glycopeptides; Antiviraux; Anticancéreux; Cyclic peptides; Glycopeptides; Antiviral; Anticancer

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Abbour, S. (2013). Pseudopeptides cycliques biocides de novo : Cyclic biocide pseudopeptides de novo. (Doctoral Dissertation). Rennes 1. Retrieved from http://www.theses.fr/2013REN1S182

Chicago Manual of Style (16^th Edition):

Abbour, Shoukri. “Pseudopeptides cycliques biocides de novo : Cyclic biocide pseudopeptides de novo.” 2013. Doctoral Dissertation, Rennes 1. Accessed January 23, 2021. http://www.theses.fr/2013REN1S182.

MLA Handbook (7^th Edition):

Abbour, Shoukri. “Pseudopeptides cycliques biocides de novo : Cyclic biocide pseudopeptides de novo.” 2013. Web. 23 Jan 2021.

Vancouver:

Abbour S. Pseudopeptides cycliques biocides de novo : Cyclic biocide pseudopeptides de novo. [Internet] [Doctoral dissertation]. Rennes 1; 2013. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2013REN1S182.

Council of Science Editors:

Abbour S. Pseudopeptides cycliques biocides de novo : Cyclic biocide pseudopeptides de novo. [Doctoral Dissertation]. Rennes 1; 2013. Available from: http://www.theses.fr/2013REN1S182

The Ohio State University

15. Upadhyaya, Punit. Discovery and Optimization of Ras Inhibitors Through Combinatorial and Medicinal Chemistry.

Degree: PhD, Chemistry, 2014, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1405516420

► Ras is a small family of proteins that are ubiquitously expressed and play critical roles in cell proliferation, differentiation and survival. Mutations in the Ras… (more)

▼ Ras is a small family of proteins that are ubiquitously expressed and play critical roles in cell proliferation, differentiation and survival. Mutations in the Ras gene are present in approximately 30 % of human cancers. These mutations result in the functional activation of Ras due to the impairment of GTP hydrolysis. Despite half a century of extensive research, no therapeutics has been very successful in clinical trials. Most of the efforts to discover inhibitors of Ras have focused on small molecules. However, this approach may not be successful, as Ras does not contain any deep binding pockets ideal for small molecule binding. The mutant K-Ras G12V is prevalent in major neoplasms that result in a high level of mortality. Unlike G12C and G12D mutants that contain a reactive moiety (thiol and carboxyl groups respectively) that can be specifically targeted with covalent inhibitors, K-Ras G12V presents a much more challenging target. Since inhibition of Ras function requires a molecule that can compete with large effector proteins for binding to Ras, we chose to screen monocyclic and bicyclic peptide libraries to obtain binders and inhibitors against K-Ras G12V. These macrocycles occupy a unique chemical space between small molecules and antibodies and currently underexplored as inhibitors of Protein Protein Interactions (PPI’s). The one bead two compound (OBTC) approach was used to design bicyclic and monocyclic libraries with the potential inhibitor displayed on the surface and the corresponding encoding tag for hit identification. We successfully incorporated unique features in the library such as the ability to selective cleave and screen cyclic peptides in solution. This feature enhances our screening procedure and reduces the time and expense associated with the screening process. The bicyclic library screening produced compounds that bound to K-Ras G12V with high affinity. Some of these inhibitors bound to the effector binding surface of Ras and inhibited their function. Other molecules bound to a different site on Ras and were unable to inhibit Ras-effector protein interaction. We were successful in finding molecules that bound specifically to activated GTP bound K-Ras G12V with 10-fold selectivity. Although the usefulness of these molecules is blunted by their lack of cellular activity, we are currently in the process of improving their properties such as cell permeability and binding affinities to address that issues.The monocyclic library produced compounds that in addition to inhibiting K-Ras in vitro, were able to inhibit growth of lung cancer cells. Despite a lack of structural information on the binding mode of these compounds with the protein, we were able to use SAR studies to obtain molecules with improved potency and cell permeability. The most potent compound, 9A5 bound to GTP-K-Ras with 6-fold selectivity. 9A5 also downregulated major signaling pathways of K-Ras and induced apoptosis in lung cancer cell lines. These compounds represent the most potent inhibitors of K-Ras (in addition to other… Advisors/Committee Members: Pei, Dehua (Advisor).

Subjects/Keywords: Chemistry; Biochemistry; Combinatorial Chemistry, Cyclic Peptides, Bicyclic Peptides, Ras Inhibitors

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Upadhyaya, P. (2014). Discovery and Optimization of Ras Inhibitors Through Combinatorial and Medicinal Chemistry. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1405516420

Chicago Manual of Style (16^th Edition):

Upadhyaya, Punit. “Discovery and Optimization of Ras Inhibitors Through Combinatorial and Medicinal Chemistry.” 2014. Doctoral Dissertation, The Ohio State University. Accessed January 23, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405516420.

MLA Handbook (7^th Edition):

Upadhyaya, Punit. “Discovery and Optimization of Ras Inhibitors Through Combinatorial and Medicinal Chemistry.” 2014. Web. 23 Jan 2021.

Vancouver:

Upadhyaya P. Discovery and Optimization of Ras Inhibitors Through Combinatorial and Medicinal Chemistry. [Internet] [Doctoral dissertation]. The Ohio State University; 2014. [cited 2021 Jan 23]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1405516420.

Council of Science Editors:

Upadhyaya P. Discovery and Optimization of Ras Inhibitors Through Combinatorial and Medicinal Chemistry. [Doctoral Dissertation]. The Ohio State University; 2014. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1405516420

University of Utah

16. Zabriskie, T. Mark. The Characterization of cytotoxic metabolites from Fijian marine invertebrates;.

Degree: PhD, Medicinal Chemistry;, 1989, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd1/id/428/rec/1348

► Marine organisms have been shown to produce a wide variety of biologically active secondary metabolites, often without precedent among known terrestrial natural products. As part… (more)

▼ Marine organisms have been shown to produce a wide variety of biologically active secondary metabolites, often without precedent among known terrestrial natural products. As part of a continuing program to screen Fijian marine invertebrates for novel bioactive compounds, two organisms, the sponge Jaspis johnstoni and the didemnid tunicate Lissoclinum patella, have been investigated. Isolation of the active constituents of these organisms was directed by various bioassays and utilized standard chromatographic techniques. The structures were solved using a variety of spectroscopic methods with the major emphasis placed on high field two-dimensional nuclear magnetic resonance (2D NMR), single crystal x-ray diffraction and tandem mass spectrometry. Several of the structure proofs also relied heavily on analysis of key degradation products. The major active metabolite in the Jaspis sponge was found to be a novel compound of mixed peptide/polyketide biosynthesis called jaspamide. Jaspamide is a potent natural insecticide and antifungal agent with moderate cytotoxicity. The 7-deazapurine nucleosides toyocamycin and 5-(methoxycarbonyl)tubercidin and the corresponding aglycones were also isolated. Previous work has shown L. patella, collected from Palau and Australia, to produce a family of cytotoxic, cyclic peptides all containing a thiazole and usually an oxazoline amino acid. In contrast, the Fijian tunicate contained a series of thiazole-containing macrolides, the patellazoles, and a group of modified, thiazoline-containing cyclic peptides, the patellins. The patellazoles were extremely effective antitumor compounds in the National Cancer Institute's human cell line protocol with mean IC(50)s of 10{-3} to less than 10{-6}mu-g/mL. They also exhibited potent antiviral activity in vitro but were too toxic for in vivo use. The structures were solved primarily using NMR techniques, including a new phase-sensitive 2D INADEQUATE experiment. The three-dimensional structure of patellin 2 was solved by x-ray crystallography and the two-dimensional structures of patellins 1 and 3-5 were assigned primarily by fast atom bombardment tandem mass spectrometry. These peptides are unique in having two modified threonine or serine dimethylallyl ethers and in the tendency for most members of the family to exist in two conformations, the ratio of which is a function of solvent.

Subjects/Keywords: Peptides, Cyclic; Porifera; Thiazoles; Urochordata

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zabriskie, T. M. (1989). The Characterization of cytotoxic metabolites from Fijian marine invertebrates;. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd1/id/428/rec/1348

Chicago Manual of Style (16^th Edition):

Zabriskie, T Mark. “The Characterization of cytotoxic metabolites from Fijian marine invertebrates;.” 1989. Doctoral Dissertation, University of Utah. Accessed January 23, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd1/id/428/rec/1348.

MLA Handbook (7^th Edition):

Zabriskie, T Mark. “The Characterization of cytotoxic metabolites from Fijian marine invertebrates;.” 1989. Web. 23 Jan 2021.

Vancouver:

Zabriskie TM. The Characterization of cytotoxic metabolites from Fijian marine invertebrates;. [Internet] [Doctoral dissertation]. University of Utah; 1989. [cited 2021 Jan 23]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd1/id/428/rec/1348.

Council of Science Editors:

Zabriskie TM. The Characterization of cytotoxic metabolites from Fijian marine invertebrates;. [Doctoral Dissertation]. University of Utah; 1989. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd1/id/428/rec/1348

Penn State University

17. El-mowafi, Shaima. Development and Validation of Screens For Drugs targeting Gram-negative Bacteria.

Degree: 2014, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/22620

► One of the greatest challenges of the twenty-first century is the development of antibiotic resistance. Selective pressure imposed by the interference of the conventional antibiotics… (more)

▼ One of the greatest challenges of the twenty-first century is the development of antibiotic resistance. Selective pressure imposed by the interference of the conventional antibiotics with essential processes has resulted in many multi-drug resistant pathogens causing several hospital-acquired and community-borne diseases. Antibiotic development is dwindling and only a limited pool of potential new drugs is available in the pharmaceutical pipeline. As a consequence, there is an urgent need for new molecular targets and new classes of antibiotics. Recently, alternative therapeutic strategies have been proposed as new treatment options. One such approach involves identification of compounds that target virulence instead of viability, thereby reducing the likelihood of developing resistance. Particularly, compounds targeting conserved regulators of virulence gene expression are expected to have broad spectrum of activity. This study describes the identification of inhibitors for the σE-sRNA-Hfq regulatory pathway. Small non-coding RNAs (sRNAs) act in conjunction with the RNA chaperone Hfq to regulate gene expression in bacteria. A subset of sRNAs that regulate expression of outer membrane proteins are transcribed using the alternative sigma factor σE. Because σE and Hfq components are required for virulence in several gram-negative pathogens and σE is required for viability of some other pathogens, the σE-sRNA-Hfq system is an attractive target for antibiotic development. To identify inhibitors of the σE-sRNA-Hfq regulatory pathway, a reporter strain was engineered in which OmpC’-YFP expression is controlled by the RybB sRNA. When the system is functional, the ompC’-yfp mRNA is degraded, resulting in no fluorescence. On the other hand, inhibition of any step in the pathway leads to OmpC’-YFP expression and fluorescent cells. This reporter was used in genetic screens to identify inhibitors from a library of cyclic peptides produced in E. coli using SICLOPPS, an intein-based technology. Assays with secondary reporter strains revealed that the identified cyclic peptides targeted different steps of the pathway. One cyclic peptide SI24 was identified as an inhibitor of σE-dependent transcription but not Hfq-RybB mediated repression. Anisotropy experiments in conjunction with in vitro transcription assays showed that SI24 binds σE, decreases the affinity of σE and RNAP and inhibits σE-RNAP holoenzyme formation. Another screen identified the cyclic peptide RI20, which inhibits Hfq-mediated repression of gene expression in conjunction with both RybB and an unrelated sRNA, MicF. Gel mobility shift assays showed that RI20 inhibits binding of Hfq to these sRNAs with similar KI values. It is likely that RI20 blocks interactions between Hfq and other sRNAs as well. Taken together, this study validates σE and Hfq as novel “druggable” targets and demonstrates that the σE-sRNA-Hfq regulatory pathway can be efficiently inhibited. The screening assay developed could be used for identification of small molecule inhibitors of the pathway.… Advisors/Committee Members: Kenneth Charles Keiler, Dissertation Advisor/Co-Advisor, Sarah Ellen Ades, Committee Member, Katsuhiko Murakami, Committee Member, Squire J Booker, Committee Member, Michael Axtell, Committee Member.

Subjects/Keywords: Gram-negative pathogens; virulence; σE-sRNA-Hfq pathway; cyclic peptides

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APA (6^th Edition):

El-mowafi, S. (2014). Development and Validation of Screens For Drugs targeting Gram-negative Bacteria. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/22620

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

El-mowafi, Shaima. “Development and Validation of Screens For Drugs targeting Gram-negative Bacteria.” 2014. Thesis, Penn State University. Accessed January 23, 2021. https://submit-etda.libraries.psu.edu/catalog/22620.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

El-mowafi, Shaima. “Development and Validation of Screens For Drugs targeting Gram-negative Bacteria.” 2014. Web. 23 Jan 2021.

Vancouver:

El-mowafi S. Development and Validation of Screens For Drugs targeting Gram-negative Bacteria. [Internet] [Thesis]. Penn State University; 2014. [cited 2021 Jan 23]. Available from: https://submit-etda.libraries.psu.edu/catalog/22620.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

El-mowafi S. Development and Validation of Screens For Drugs targeting Gram-negative Bacteria. [Thesis]. Penn State University; 2014. Available from: https://submit-etda.libraries.psu.edu/catalog/22620

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Hong Kong University of Science and Technology

18. Ng, Na Lee. Optimization of antibacterial cyclic decapeptides : tyrocidine A.

Degree: 2004, Hong Kong University of Science and Technology

URL: http://repository.ust.hk/ir/Record/1783.1-4032 ; https://doi.org/10.14711/thesis-b843351 ; http://repository.ust.hk/ir/bitstream/1783.1-4032/1/th_redirect.html

► Microbial resistance to currently available antibiotics has become an increasing threat to public health. The cyclic dodecapetide tyrocidine A produced by Bacillus brevis is an… (more)

▼ Microbial resistance to currently available antibiotics has become an increasing threat to public health. The cyclic dodecapetide tyrocidine A produced by Bacillus brevis is an attractive template for drug development to counter the resistance because it disrupts cell membranes in its bactericidal function and, as a result, unlikely to provoke new resistance. However, this natural product kills both bacteria and mammalian cells indiscriminately and is limited from direct application in treatment of resistant microbes. A novel method for parallel synthesis of cyclic peptides was previously developed to increase the cell-differentiating ability of the template tyrocidine A. In this thesis, this synthetic method is studied with circular dichroism (CD) spectroscopy and applied to optimize the biological functions of tyrocidine A. Comparison of the CD spectra of the linear and cyclic tyrocidine A found that the linear precursor adopts a β-pleated sheet structure closely resembling the cyclic product which is thermally stable in various media. This provides strong evidence that the linear precursor is predisposed to a favorable conformation that facilitates the head-to-tail ring closure observed in the synthetic method. Subsequently, two approaches were undertaken to optimize the natural antibiotic. First, using the conformation-dependent cyclization method, constituent amino acids of tyrocidine A were individually substituted with alanine and screening of the resulting analogues revealed that both antibacterial and hemolytic activities of the tyrocidine A are most susceptible to substitution at glutamine-5. Display of a variety of side chains at this position resulted in successful dissociation of the two intimately associated properties and identification of analogues with a therapeutic index up to 140. In a second approach, a 192-membered library was designed on the basis of the structural differences between the natural cyclic antibiotics tyrocidines, streptocidines, and loloatins, and successfully constructed with the developed method. Screening of the library identified three analogues with 10 to 90-fold increase in therapeutic index and concurrent increase in antibacterial activity. These newly discovered analogues are promising leads for further drug development to combat the microbial resistance.

Subjects/Keywords: Peptide antibiotics ; Cyclic peptides ; Tyrocidines

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ng, N. L. (2004). Optimization of antibacterial cyclic decapeptides : tyrocidine A. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-4032 ; https://doi.org/10.14711/thesis-b843351 ; http://repository.ust.hk/ir/bitstream/1783.1-4032/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ng, Na Lee. “Optimization of antibacterial cyclic decapeptides : tyrocidine A.” 2004. Thesis, Hong Kong University of Science and Technology. Accessed January 23, 2021. http://repository.ust.hk/ir/Record/1783.1-4032 ; https://doi.org/10.14711/thesis-b843351 ; http://repository.ust.hk/ir/bitstream/1783.1-4032/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ng, Na Lee. “Optimization of antibacterial cyclic decapeptides : tyrocidine A.” 2004. Web. 23 Jan 2021.

Vancouver:

Ng NL. Optimization of antibacterial cyclic decapeptides : tyrocidine A. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2004. [cited 2021 Jan 23]. Available from: http://repository.ust.hk/ir/Record/1783.1-4032 ; https://doi.org/10.14711/thesis-b843351 ; http://repository.ust.hk/ir/bitstream/1783.1-4032/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ng NL. Optimization of antibacterial cyclic decapeptides : tyrocidine A. [Thesis]. Hong Kong University of Science and Technology; 2004. Available from: http://repository.ust.hk/ir/Record/1783.1-4032 ; https://doi.org/10.14711/thesis-b843351 ; http://repository.ust.hk/ir/bitstream/1783.1-4032/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Aberdeen

19. Dalponte, Luca. Chemo-enzymatic modification of cyclic peptides.

Degree: PhD, 2018, University of Aberdeen

URL: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152847350005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760029

Subjects/Keywords: 540; Cyclic peptides; Enzymes

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APA (6^th Edition):

Dalponte, L. (2018). Chemo-enzymatic modification of cyclic peptides. (Doctoral Dissertation). University of Aberdeen. Retrieved from https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152847350005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760029

Chicago Manual of Style (16^th Edition):

Dalponte, Luca. “Chemo-enzymatic modification of cyclic peptides.” 2018. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152847350005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760029.

MLA Handbook (7^th Edition):

Dalponte, Luca. “Chemo-enzymatic modification of cyclic peptides.” 2018. Web. 23 Jan 2021.

Vancouver:

Dalponte L. Chemo-enzymatic modification of cyclic peptides. [Internet] [Doctoral dissertation]. University of Aberdeen; 2018. [cited 2021 Jan 23]. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152847350005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760029.

Council of Science Editors:

Dalponte L. Chemo-enzymatic modification of cyclic peptides. [Doctoral Dissertation]. University of Aberdeen; 2018. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152847350005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760029

Washington University in St. Louis

20. Rensing, Derek Thomas. Synthesis of Simplified YM-254890 Analogs.

Degree: PhD, Chemistry, 2016, Washington University in St. Louis

URL: https://openscholarship.wustl.edu/art_sci_etds/888

► G Protein Coupled Receptors (GPCR’s) are responsible for a multitude of physiological, cellular, and disease processes. GPCR’s signal through non-receptor based heterotrimeric G proteins… (more)

▼ G Protein Coupled Receptors (GPCR’s) are responsible for a multitude of physiological, cellular, and disease processes. GPCR’s signal through non-receptor based heterotrimeric G proteins and since G proteins effectively mediate GPCR signal transduction they are attractive therapeutic targets. However, little is known about the signaling pathways associated with individual G proteins. For this reason, there is intense interest in the development of chemical probes that can help identify the downstream biochemistry of individual G proteins. One small molecule natural product that shows promise along these lines is YM-254890 (YM). YM has been shown to specifically and potently inhibit the α subunit of the G protein Gq. Further studies of the natural product have been hampered because YM has yet to be synthesized due to its complex cyclic depsipeptide structure. By studying the X-ray crystal structure of YM bound to Gqα, the contact points between the molecule and the protein have been elucidated, and from this we targeted a simplified analog substructure. This analog structure preserves the protein contact points of YM while reducing the complexity of 22 member ring structure of YM. The heart of the project undertaken centers on the development of a convergent synthetic route to the analog’s core ring structure that is general enough to enable the synthesis of a variety of derivatives in the future. To this effect we have synthesized two different YM analogs. The first, WU-07047, was completed with an overall yield of 6.4% and a longest linear reaction sequence of 10 steps. Initial biological testing of WU-07047 has shown that the simplified molecule is biologically active, albeit at a less potent level than YM. We currently have multiple collaborators testing the effectiveness of WU-07047 in different in-vivo studies. Before undertaking further biological studies in our labs, we wanted to increase the potency of the molecule. To this end we reintroduced an intramolecular hydrogen bond in the molecule that had been lost in simplified WU-0747 molecule. The 2nd molecule synthesized, WU-09060, was completed using the same convergent synthetic approach developed for WU-07047 and yielded the target molecule with an overall yield of 1.8% and a longest linear reaction sequence of 10 steps. Initial biological testing has shown that the reintroduction of the intramolecular hydrogen bond has had little effect on the potency of the molecule and therefore is not worth the extra synthetic effort. During the synthesis of the WU-09060 molecule we were also able to probe the effects of the top bridging structure of the molecule on ease of overall molecule synthesis, which has larger implications on the synthesis of this class of molecule. Advisors/Committee Members: Kevin D. Moeller, John-Stephen Taylor, Vladimir Birman, Kendall J. Blumer, Garland Marshall.

Subjects/Keywords: Cyclic Peptides; Depsipeptide; G Proteins; Total Synthesis; YM-254890

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rensing, D. T. (2016). Synthesis of Simplified YM-254890 Analogs. (Doctoral Dissertation). Washington University in St. Louis. Retrieved from https://openscholarship.wustl.edu/art_sci_etds/888

Chicago Manual of Style (16^th Edition):

Rensing, Derek Thomas. “Synthesis of Simplified YM-254890 Analogs.” 2016. Doctoral Dissertation, Washington University in St. Louis. Accessed January 23, 2021. https://openscholarship.wustl.edu/art_sci_etds/888.

MLA Handbook (7^th Edition):

Rensing, Derek Thomas. “Synthesis of Simplified YM-254890 Analogs.” 2016. Web. 23 Jan 2021.

Vancouver:

Rensing DT. Synthesis of Simplified YM-254890 Analogs. [Internet] [Doctoral dissertation]. Washington University in St. Louis; 2016. [cited 2021 Jan 23]. Available from: https://openscholarship.wustl.edu/art_sci_etds/888.

Council of Science Editors:

Rensing DT. Synthesis of Simplified YM-254890 Analogs. [Doctoral Dissertation]. Washington University in St. Louis; 2016. Available from: https://openscholarship.wustl.edu/art_sci_etds/888

University of Hong Kong

21. 渠瑾. Novel helices, reversed turns and cyclic peptides containing alpha-aminoxy acids.

Degree: 2001, University of Hong Kong

URL: http://hdl.handle.net/10722/35657

Subjects/Keywords: Cyclic compounds.; Peptides.; Amino acids.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

渠瑾. (2001). Novel helices, reversed turns and cyclic peptides containing alpha-aminoxy acids. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/35657

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

渠瑾. “Novel helices, reversed turns and cyclic peptides containing alpha-aminoxy acids.” 2001. Thesis, University of Hong Kong. Accessed January 23, 2021. http://hdl.handle.net/10722/35657.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

渠瑾. “Novel helices, reversed turns and cyclic peptides containing alpha-aminoxy acids.” 2001. Web. 23 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

渠瑾. Novel helices, reversed turns and cyclic peptides containing alpha-aminoxy acids. [Internet] [Thesis]. University of Hong Kong; 2001. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10722/35657.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

渠瑾. Novel helices, reversed turns and cyclic peptides containing alpha-aminoxy acids. [Thesis]. University of Hong Kong; 2001. Available from: http://hdl.handle.net/10722/35657

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

22. Gohard, Florence Helen. Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides.

Degree: PhD, 2015, University of Edinburgh

URL: http://hdl.handle.net/1842/10456

► The chromosome passenger complex (CPC) is an essential mitotic regulator with key roles in mitotic processes such as chromosome condensation, spindle dynamics, chromosome bi-orientation, the… (more)

▼ The chromosome passenger complex (CPC) is an essential mitotic regulator with key roles in mitotic processes such as chromosome condensation, spindle dynamics, chromosome bi-orientation, the spindle checkpoint and cytokinesis. The Aurora B kinase is the CPC’s catalytic subunit. Its targeting and activation are dependent on interactions with the other components of the complex: inner centromere protein (INCENP), survivin and borealin/Dasra B. INCENP serves both as a scaffolding subunit for the CPC as a whole and as an activator of Aurora B via its highly conserved INbox domain. Aurora B is a putative anti‐cancer target; several inhibitors of the kinase are currently in clinical trials. All these are ATP-analogues targeting the kinase active site. The protein-protein interaction between Aurora B and the INCENP INbox is also essential for CPC function. Earlier studies have demonstrated that INCENP INbox mutants unable to bind and/or activate Aurora B cannot rescue lethality in the absence of endogenous INCENP. The first goal of this study was to test the in vivo effects of disrupting the interaction between endogenous wild type INCENP and Aurora B. For this, a cell-based CPC function assay was developed in HeLa cells. Using this assay, I show that expression of soluble INbox in HeLa cells produces a significant increase in multinucleated and micronucleated cells: both effects consistent with Aurora B loss of function. Expression of soluble INbox bearing the mutations W845G and/or F881A does not elicit this effect suggesting that those mutants cannot bind to Aurora B and occlude INCENP binding. The result concerning the F881A mutant contrasts with earlier reports that equivalent mutants could bind, but not activate, Aurora B. Expression of an INbox mutant lacking the C-terminal TSS motif reported to be involved in Aurora B activation but not binding has effects similar to those of the wild type INbox. Using the INbox/Aurora B interaction as a model, a secondary goal of this study was to develop and evaluate a novel approach to identify small peptides capable of dissociating intracellular protein‐protein interactions. For this, a library of small (5-9 residues long) circular peptides (CPs) mimicking the INbox was generated using the split intein circular ligation of proteins and peptides (SICLOPPS) methodology and assayed using the cell-based CPC function assay. Over two successive rounds of screening, a small number of CPs were identified that caused a significant increase in rates of multinucleated and micronucleated cells. Although statistically significant, these increases were very modest. Furthermore, due to high heterogeneity in SICLOPPS processing efficiencies, it was not practicable to compare the effects of different peptides side-by-side by transfection. The level of variation in processing efficiency – thus, CP production – was unexpectedly high and puts into question the functional complexity of more commonly used combinatorial cyclic peptide libraries derived using current SICLOPPS methodology. The…

Subjects/Keywords: 572; Aurora B; chromosome passenger complex; CPC; INCENP; cyclic peptides

10 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gohard, F. H. (2015). Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/10456

Chicago Manual of Style (16^th Edition):

Gohard, Florence Helen. “Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides.” 2015. Doctoral Dissertation, University of Edinburgh. Accessed January 23, 2021. http://hdl.handle.net/1842/10456.

MLA Handbook (7^th Edition):

Gohard, Florence Helen. “Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides.” 2015. Web. 23 Jan 2021.

Vancouver:

Gohard FH. Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides. [Internet] [Doctoral dissertation]. University of Edinburgh; 2015. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/1842/10456.

Council of Science Editors:

Gohard FH. Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides. [Doctoral Dissertation]. University of Edinburgh; 2015. Available from: http://hdl.handle.net/1842/10456

Heriot-Watt University

23. Gilfillan, Robert. Studies on the synthesis and host-guest properties of polycyclic peptides.

Degree: PhD, 1997, Heriot-Watt University

URL: http://hdl.handle.net/10399/1100

Subjects/Keywords: 547; Cyclic peptides; Binding; Receptor

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gilfillan, R. (1997). Studies on the synthesis and host-guest properties of polycyclic peptides. (Doctoral Dissertation). Heriot-Watt University. Retrieved from http://hdl.handle.net/10399/1100

Chicago Manual of Style (16^th Edition):

Gilfillan, Robert. “Studies on the synthesis and host-guest properties of polycyclic peptides.” 1997. Doctoral Dissertation, Heriot-Watt University. Accessed January 23, 2021. http://hdl.handle.net/10399/1100.

MLA Handbook (7^th Edition):

Gilfillan, Robert. “Studies on the synthesis and host-guest properties of polycyclic peptides.” 1997. Web. 23 Jan 2021.

Vancouver:

Gilfillan R. Studies on the synthesis and host-guest properties of polycyclic peptides. [Internet] [Doctoral dissertation]. Heriot-Watt University; 1997. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10399/1100.

Council of Science Editors:

Gilfillan R. Studies on the synthesis and host-guest properties of polycyclic peptides. [Doctoral Dissertation]. Heriot-Watt University; 1997. Available from: http://hdl.handle.net/10399/1100

University of New South Wales

24. Ahmed, Md. Iqbal. Conformational fine-tuning of cyclic peptides: a strategy for improving cyclisation efficiency and biological activity.

Degree: Chemistry, 2015, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/55349 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37335/SOURCE02?view=true

► Cyclic peptides are valuable lead compounds for the development of medicines targeting many different diseases, due to their high stability and their often strong affinity… (more)

▼ Cyclic peptides are valuable lead compounds for the development of medicines targeting many different diseases, due to their high stability and their often strong affinity for biological targets. However, the synthesis of cyclic peptides is often inefficient, and their 3D shapes are not always optimal for target binding. This project aimed to provide a solution to both of these problems. The cyclic peptide Sansalvamide A (San A) was selected as the scaffold for this project. San A is a pentapeptide that has potent activity against various cancer cell lines, but its medicinal development is hampered by synthetic difficulties. First, a series of analogues of San A were synthesised by incrementally increasing the flexibility of peptide backbone using glycine, beta-alanine or gamma-aminobutyric acid (GABA) in place of a leucine residue of San A. These replacements were shown to dramatically increase the efficiency of peptide cyclisation, which was rationalised by comparing the effective molarity (EM) of cyclisation of the corresponding linear precursor peptides.Second, the cytotoxicity of the synthesised analogues was tested against human colon cancer cells. Overall, the analogues exhibited weaker activity than San A itself. However, the GABA-containing analogue had the most promising activity. Therefore this analogue was selected for further development.Third, a series of conformationally-restricted GABA derivatives were targeted, in order to “rescue” the San A activity while retaining cyclisation efficiency. The library of GABA derivatives included two unusual backbone-fluorinated amino acids; these had previously been synthesised in the Hunter group, but the synthesis was inefficient. Accordingly, a new synthetic route was developed. The conformationally-restricted GABA derivatives were then elaborated into new San A analogues, and the cytotoxicity was measured.Finally, to rationalise the observed trends in biological activity, preliminary efforts were made to determine the 3D geometries of all San A analogues synthesised by performing a series of NMR and molecular modelling experiments. Overall, this project has contributed significantly to the medicinal development of cyclic peptides, by developing a new strategy for improving peptide cyclisation efficiency and by highlighting a new class of selectively fluorinated amino acids as novel tools for “fine-tuning” the conformations of cyclic peptides. Advisors/Committee Members: Hunter, Luke, Chemistry, Faculty of Science, UNSW, McAlpine, Shelli Renee, Chemistry, Faculty of Science, UNSW.

Subjects/Keywords: Gamma-aminobutyric acid (GABA); Cyclic peptides; Effective molarity; Backbone-fluorinated

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APA (6^th Edition):

Ahmed, M. I. (2015). Conformational fine-tuning of cyclic peptides: a strategy for improving cyclisation efficiency and biological activity. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/55349 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37335/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Ahmed, Md Iqbal. “Conformational fine-tuning of cyclic peptides: a strategy for improving cyclisation efficiency and biological activity.” 2015. Doctoral Dissertation, University of New South Wales. Accessed January 23, 2021. http://handle.unsw.edu.au/1959.4/55349 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37335/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Ahmed, Md Iqbal. “Conformational fine-tuning of cyclic peptides: a strategy for improving cyclisation efficiency and biological activity.” 2015. Web. 23 Jan 2021.

Vancouver:

Ahmed MI. Conformational fine-tuning of cyclic peptides: a strategy for improving cyclisation efficiency and biological activity. [Internet] [Doctoral dissertation]. University of New South Wales; 2015. [cited 2021 Jan 23]. Available from: http://handle.unsw.edu.au/1959.4/55349 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37335/SOURCE02?view=true.

Council of Science Editors:

Ahmed MI. Conformational fine-tuning of cyclic peptides: a strategy for improving cyclisation efficiency and biological activity. [Doctoral Dissertation]. University of New South Wales; 2015. Available from: http://handle.unsw.edu.au/1959.4/55349 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37335/SOURCE02?view=true

University of Texas – Austin

25. Crittenden, Christopher Martin. Tandem mass spectrometry approaches to characterizing challenging biomolecules : stapled and cyclic peptides and variants of lipid A from gram-negative bacteria.

Degree: MA, Chemistry, 2016, University of Texas – Austin

URL: http://hdl.handle.net/2152/44012

► Mass spectrometry has emerged as a leading tool in the field of chemistry as an analytical method for the characterization of small molecules, proteins, and… (more)

▼ Mass spectrometry has emerged as a leading tool in the field of chemistry as an analytical method for the characterization of small molecules, proteins, and other complex biomolecules. Specifically, cyclic and stapled peptides have become an intriguing class of biomolecules in drug research afforded to them because of their biological stability and resistance to proteolytic digestions. However, challenges are presented in regards to the characterization of these molecules as traditional methods are ineffective in determining a ring-opening site on the peptidic backbone. Additionally, lipid A, the hydrophobic domain of lipopolysaccharide (LPS), consists of a diglucosamine backbone and is responsible for fastening LPS to a membrane surface. Lipid A becomes a biologically relevant molecule to study as its function within LPS is directly related to the infectious and toxic properties of gram-negative bacteria, but the molecule is structurally complex and offers many challenges in terms of traditional mass spectrometry characterization. Presented in the thesis are methods to further comprehend structural motifs related to the aforementioned biomolecules. The “ornithine effect”, which describes the conversion of an arginine residue to an ornithine residue via reaction with hydrazine and subsequent preferential cyclization via nucleophilic attack of the ornithine side-chain to the neighboring carbonyl group, inducing heterolytic cleavage of the adjacent amide bond under gentle activation, is used to preferentially open cyclic and stapled rings to linearize these challenging biomolecules. Ramped collisional and photon based activation (in terms of energy and laser pulses) of lipid A molecules that contain differences in acyl-chain length and connectivity reveal general trends about the lability of certain bonds on the lipid A molecules themselves and paints a picture of the overall fragmentation trends associated with variations in lipid A structural motifs. Advisors/Committee Members: Brodbelt, Jennifer S. (advisor), Mullins, Charles B (committee member).

Subjects/Keywords: Mass spectrometry; Analytical; Photodissociation; Chemistry; Lipids; Cyclic peptides

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APA (6^th Edition):

Crittenden, C. M. (2016). Tandem mass spectrometry approaches to characterizing challenging biomolecules : stapled and cyclic peptides and variants of lipid A from gram-negative bacteria. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/44012

Chicago Manual of Style (16^th Edition):

Crittenden, Christopher Martin. “Tandem mass spectrometry approaches to characterizing challenging biomolecules : stapled and cyclic peptides and variants of lipid A from gram-negative bacteria.” 2016. Masters Thesis, University of Texas – Austin. Accessed January 23, 2021. http://hdl.handle.net/2152/44012.

MLA Handbook (7^th Edition):

Crittenden, Christopher Martin. “Tandem mass spectrometry approaches to characterizing challenging biomolecules : stapled and cyclic peptides and variants of lipid A from gram-negative bacteria.” 2016. Web. 23 Jan 2021.

Vancouver:

Crittenden CM. Tandem mass spectrometry approaches to characterizing challenging biomolecules : stapled and cyclic peptides and variants of lipid A from gram-negative bacteria. [Internet] [Masters thesis]. University of Texas – Austin; 2016. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2152/44012.

Council of Science Editors:

Crittenden CM. Tandem mass spectrometry approaches to characterizing challenging biomolecules : stapled and cyclic peptides and variants of lipid A from gram-negative bacteria. [Masters Thesis]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/44012

Indian Institute of Science

26. Sonti, Rajesh. Conformational Analysis of Designed and Natural Peptides : Studies of Aromatic/Aromatic and Aromatic/Proline Interactions by NMR.

Degree: PhD, Faculty of Science, 2018, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/3335

► This thesis describes NMR studies which probe weak interactions between amino acid side chains in folded peptide structures. Aromatic/aromatic interactions between facing phenylalanine residues have… (more)

▼ This thesis describes NMR studies which probe weak interactions between amino acid side chains in folded peptide structures. Aromatic/aromatic interactions between facing phenylalanine residues have been probed in antiparallel β-sheets, while aromatic/proline interactions have been examined using cyclic peptide disulfides that occur in the venom of marine cone snails. Novel intramolecular hydrogen bonded structures in hybrid peptides containing backbone homologated residues, specifically γ-amino acids, are also described. Chapter 1 provides a brief background to the principles involved in the design of antiparallel β-sheet structures and an introduction to previous studies on aromatic/aromatic and aromatic/proline interactions in influencing peptide conformations. A summary of the NMR methods used is also presented. Chapter 2 discusses the structural characterisation of a designed 14 residue, three stranded β-sheet peptide, Boc-LFVDP-PLFVADP-PLFV-OMe (LFV14). The results described in this Chapter support the presence of multiple conformational states about the χ1 (Cα-Cβ) torsional degree of freedom for the interacting aromatic pairs in solution. Chapter 3 presents the structural characterisation of a designed 19 residue three stranded hybrid β-sheet peptide, Boc-LVβFVDPGLβFVVLDPGLVLβFVV-OMe (BBH19). β-amino acid residues (β-phenylalanine, βPhe) were incorporated at facing positions on antiparallel β-sheets. The BBH19 structure provides an example of interaction between the N and C-terminal strands in a three stranded structure with an α/β hybrid backbone. Chapter 4 focuses on studies of the conformations of the contryphan In936 (GCVDLYPWC*) from Conus inscriptus and the related peptide Lo959 (GCPDWDPWC*) from Conus loroissi. Both peptides possess a macrocyclic 23 membered ring, with multiple accessible conformational states. Chapter 5 describes conformational analysis of a novel 20 membered cyclic peptide disulfide, CIWPWC (Vi804), from Conus virgo. NMR structures were calculated for Vi804 and an analog peptide, CIDWPWC, DW3-Vi804. Chapter 6 explores the solution conformation of hybrid sequences containing α and γ residues. Oligopeptides of the type (αγ)n and (αγγ)n have been studied in solution by NMR methods. Chapter 7 provides a summary of the results described in this thesis and highlights the major conclusions. Advisors/Committee Members: Balaram, P (advisor).

Subjects/Keywords: Natural Peptides; Aromatic/Aromatic Interactions; Aromatic/Proline Interactions; Peptides - Conformational Analysis; Nuclear Magnetic Resonance; Cyclic Peptide Disulfides; Cyclic Peptides; Hybrid Peptides; Beta Hairpins; Beta Sheets; Cyclic Peptide Disulfides; Designed Peptides; Proteins - Analysis; β-Hairpin; β-sheet Peptide; α/β Hybrid Peptide; Biochemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sonti, R. (2018). Conformational Analysis of Designed and Natural Peptides : Studies of Aromatic/Aromatic and Aromatic/Proline Interactions by NMR. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/3335

Chicago Manual of Style (16^th Edition):

Sonti, Rajesh. “Conformational Analysis of Designed and Natural Peptides : Studies of Aromatic/Aromatic and Aromatic/Proline Interactions by NMR.” 2018. Doctoral Dissertation, Indian Institute of Science. Accessed January 23, 2021. http://etd.iisc.ac.in/handle/2005/3335.

MLA Handbook (7^th Edition):

Sonti, Rajesh. “Conformational Analysis of Designed and Natural Peptides : Studies of Aromatic/Aromatic and Aromatic/Proline Interactions by NMR.” 2018. Web. 23 Jan 2021.

Vancouver:

Sonti R. Conformational Analysis of Designed and Natural Peptides : Studies of Aromatic/Aromatic and Aromatic/Proline Interactions by NMR. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2018. [cited 2021 Jan 23]. Available from: http://etd.iisc.ac.in/handle/2005/3335.

Council of Science Editors:

Sonti R. Conformational Analysis of Designed and Natural Peptides : Studies of Aromatic/Aromatic and Aromatic/Proline Interactions by NMR. [Doctoral Dissertation]. Indian Institute of Science; 2018. Available from: http://etd.iisc.ac.in/handle/2005/3335

Nelson Mandela Metropolitan University

27. Kilian, Gareth. Development and testing of liposome encapsulated cyclic dipeptides.

Degree: PhD, Faculty of Health Sciences, 2011, Nelson Mandela Metropolitan University

URL: http://hdl.handle.net/10948/1397

► Cyclic dipeptides have been well characterized for their multitude of biological activities, including antimicrobial and anticancer activities. Cyclo(His-Gly) and cyclo(His-Ala) have also recently been shown… (more)

▼ Cyclic dipeptides have been well characterized for their multitude of biological activities, including antimicrobial and anticancer activities. Cyclo(His-Gly) and cyclo(His-Ala) have also recently been shown to possess significant anticancer activity against a range of cell lines, despite the limitations of these two molecules with respect to their physicochemical properties. Low Log P results in poor cell permeability which can often be problematic for drugs with intracellular mechanisms of action. It can also results in poor biodistribution, and theoretical Log P values for cyclo(His-Gly) and cyclo(His-Ala) were extremely low making them ideal candidates for inclusion into a nanoparticulate drug delivery system. The aim of this study was therefore to formulate and evaluate liposome-encapsulated cyclic dipeptides that increase the tumour-suppressive actions of the cyclic dipeptides, while showing a high degree of specificity for tumour cells. While liposomes are relatively simple to prepare, inter batch variation, low encapsulation and poor stability are often problematic in their production and this has lead to very few liposomal products on the market. This study aimed at using a comprehensive statistical methodology in optimizing liposome formulations encapsulating cyclo(His-Gly) and cyclo(His-Ala). Initial screening of potential factors was conducted using a 25-1 fractional factorial design. This design made use of two levels for each of the five factors and abbreviated the design to minimize runs. Although not much information is provided by these types of designs, the design was sufficient in identifying two critical factors that would be studies further in a more robust design. The two factors selected, based on the screening study, were cholesterol and stearylamine content. These two factors were then used in designing a response surface methodology (RSM) design making use of a central composite rotatable vii design (CCRD) at five levels (-1.5, -1, 0, 1, 1.5) for each factor in order to better understand the design space. Various factors influenced the measured responses of encapsulation efficiency, zeta potential, polydispersity index, cellular uptake and leakage, but most notable were the adverse effects of increasing stearylamine levels on encapsulations efficiency and cholesterol levels on leakage for both cyclo(His-Gly) and cyclo(His-Ala) liposomes. Optimized formulations were derived from the data and prepared. Fair correlation between the predicted and measured responses was obtained. The cytotoxic activity of the encapsulated cyclic dipeptides were assessed against HeLa and MCF-7 cells and found to have limited improvement in activity. However, modification of the polyethylene glycol (PEG) grafted to the liposome surface in order to target folate receptors showed good benefit in significantly decreasing the IC50 values recorded in all cells lines tested, particularly low folate HeLa cells with the lowest IC50 being recorded as 0.0962 mM for folate targeted cyclo(His-Ala). The results therefore… Advisors/Committee Members: Milne, P J Prof.

Subjects/Keywords: Peptide antibiotics; Peptide drugs – Therapeutic use; Peptides – Synthesis; Antibacterial agents – Therapeutic use – Testing; Cyclic peptides; Liposomes

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kilian, G. (2011). Development and testing of liposome encapsulated cyclic dipeptides. (Doctoral Dissertation). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/1397

Chicago Manual of Style (16^th Edition):

Kilian, Gareth. “Development and testing of liposome encapsulated cyclic dipeptides.” 2011. Doctoral Dissertation, Nelson Mandela Metropolitan University. Accessed January 23, 2021. http://hdl.handle.net/10948/1397.

MLA Handbook (7^th Edition):

Kilian, Gareth. “Development and testing of liposome encapsulated cyclic dipeptides.” 2011. Web. 23 Jan 2021.

Vancouver:

Kilian G. Development and testing of liposome encapsulated cyclic dipeptides. [Internet] [Doctoral dissertation]. Nelson Mandela Metropolitan University; 2011. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10948/1397.

Council of Science Editors:

Kilian G. Development and testing of liposome encapsulated cyclic dipeptides. [Doctoral Dissertation]. Nelson Mandela Metropolitan University; 2011. Available from: http://hdl.handle.net/10948/1397

Georgia Tech

28. Arrowood, Kimberly Ann. Combining cyclic peptides with metal coordination.

Degree: MS, Chemistry and Biochemistry, 2009, Georgia Tech

URL: http://hdl.handle.net/1853/29700

► This thesis targets cyclic peptide supramolecular structures for biomaterial applications. The introduction gives a brief insight into supramolecular interactions, peptides, and their application in biomaterials.… (more)

Subjects/Keywords: Cyclic peptides; Supramolecular chemistry; Metal coordination; Cyclic peptides; Biomedical materials; Supramolecular chemistry

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APA (6^th Edition):

Arrowood, K. A. (2009). Combining cyclic peptides with metal coordination. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/29700

Chicago Manual of Style (16^th Edition):

Arrowood, Kimberly Ann. “Combining cyclic peptides with metal coordination.” 2009. Masters Thesis, Georgia Tech. Accessed January 23, 2021. http://hdl.handle.net/1853/29700.

MLA Handbook (7^th Edition):

Arrowood, Kimberly Ann. “Combining cyclic peptides with metal coordination.” 2009. Web. 23 Jan 2021.

Vancouver:

Arrowood KA. Combining cyclic peptides with metal coordination. [Internet] [Masters thesis]. Georgia Tech; 2009. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/1853/29700.

Council of Science Editors:

Arrowood KA. Combining cyclic peptides with metal coordination. [Masters Thesis]. Georgia Tech; 2009. Available from: http://hdl.handle.net/1853/29700

NSYSU

29. Liu, Che-Hsi. Exploring the allylic chalcogen effect in enyne metathesis and application towards bicyclic peptide synthesis.

Degree: Master, Chemistry, 2016, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0714116-212256

► Enyne metathesis is a metathesis reaction between an alkyne and an alkene in the presence of metal carbene catalyst forming a conjugate diene as the… (more)

Subjects/Keywords: aqueous reaction; enyne metathesis reaction; allylic chalcogen; cyclic peptides; ring-closing metathesis

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APA (6^th Edition):

Liu, C. (2016). Exploring the allylic chalcogen effect in enyne metathesis and application towards bicyclic peptide synthesis. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0714116-212256

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liu, Che-Hsi. “Exploring the allylic chalcogen effect in enyne metathesis and application towards bicyclic peptide synthesis.” 2016. Thesis, NSYSU. Accessed January 23, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0714116-212256.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liu, Che-Hsi. “Exploring the allylic chalcogen effect in enyne metathesis and application towards bicyclic peptide synthesis.” 2016. Web. 23 Jan 2021.

Vancouver:

Liu C. Exploring the allylic chalcogen effect in enyne metathesis and application towards bicyclic peptide synthesis. [Internet] [Thesis]. NSYSU; 2016. [cited 2021 Jan 23]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0714116-212256.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liu C. Exploring the allylic chalcogen effect in enyne metathesis and application towards bicyclic peptide synthesis. [Thesis]. NSYSU; 2016. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0714116-212256

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Santa Cruz

30. Schwochert, Joshua Allen. Pharmacokinetic and Conformational Analysis of Naturally Inspired Cyclic Peptides.

Degree: Chemistry, 2017, University of California – Santa Cruz

URL: http://www.escholarship.org/uc/item/7744s04p

► Research into macrocycles as an emerging class of pharmaceutically relevant molecules has increased in recent years. Advances in combinatorial chemistry and screening have yielded a… (more)

▼ Research into macrocycles as an emerging class of pharmaceutically relevant molecules has increased in recent years. Advances in combinatorial chemistry and screening have yielded a number of potent macrocycles against challenging protein targets. Although they often exhibit favorable target binding characteristics, with long off rates and high specificity, they generally tend to suffer from an inability to cross cellular membranes and are thus limited to extracellular targets. By contrast, some cyclic peptide natural products or derivatives thereof are cell permeable. This observation has led to a surge of interest in understanding the factors that govern ADME characteristics such as cell permeability, solubility and plasma stability, in medium- and large-ring macrocycles. Additionally, new synthetic strategies that allow for the synthesis of more diverse macrocycles, especially those mimicking natural products, are desired.First we investigate a cyclic peptide scaffold able to undergo an N-to-O acyl rearrangement. Despite the prevalence of head-to-side chain threonine linkages in natural products, their incorporation has been underexplored in synthetic cyclic peptides. Upon acylation of the amine with diverse carboxylic acids, the resulting cyclic depsipeptides displayed favorable cellular permeability and a conformation similar to the parent peptide. The rearrangement was found to be scaffold and conformation dependent as evidenced by molecular dynamics experiments.Additionally, we report on the effect of peptide-to-peptoid substitutions on the passive membrane permeability of an N-methylated cyclic hexapeptide. In general, substitutions maintained permeability but increased conformational heterogeneity. Diversification with nonproteinogenic side chains increased permeability up to 3-fold. Additionally, the conformational impact of peptoid substitutions within a β-turn are explored. Based on these results, the strategic incorporation of peptoid residues into cyclic peptides can maintain or improve cell permeability, while increasing access to diverse side-chain functionality.Finally, we identified the phepropeptins as natural product cyclic peptides with potential cell permeability. Synthesis of the phepropeptins and epimeric analogues revealed much more rapid cellular permeability for the natural stereochemical pattern. Despite being more cell permeable, the natural compounds exhibited similar aqueous solubility as the corresponding epimers, a phenomenon explained by solvent-dependent conformational flexibility among the natural compounds. When analyzing the polarity of the solution structures we found that neither the number of hydrogen bonds nor the total polar surface area accurately represents the solvation energies of the high and low dielectric conformations. This work adds to a growing number of natural cyclic peptides whose solvent-dependent conformational behavior allows for a balance between aqueous solubility and cell permeability, highlighting structural flexibility as an important…

Subjects/Keywords: Chemistry; Pharmaceutical sciences; cell permeability; cyclic peptides; macrocycle; natural products; peptide; synthesis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Schwochert, J. A. (2017). Pharmacokinetic and Conformational Analysis of Naturally Inspired Cyclic Peptides. (Thesis). University of California – Santa Cruz. Retrieved from http://www.escholarship.org/uc/item/7744s04p

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Schwochert, Joshua Allen. “Pharmacokinetic and Conformational Analysis of Naturally Inspired Cyclic Peptides.” 2017. Thesis, University of California – Santa Cruz. Accessed January 23, 2021. http://www.escholarship.org/uc/item/7744s04p.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Schwochert, Joshua Allen. “Pharmacokinetic and Conformational Analysis of Naturally Inspired Cyclic Peptides.” 2017. Web. 23 Jan 2021.

Vancouver:

Schwochert JA. Pharmacokinetic and Conformational Analysis of Naturally Inspired Cyclic Peptides. [Internet] [Thesis]. University of California – Santa Cruz; 2017. [cited 2021 Jan 23]. Available from: http://www.escholarship.org/uc/item/7744s04p.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Schwochert JA. Pharmacokinetic and Conformational Analysis of Naturally Inspired Cyclic Peptides. [Thesis]. University of California – Santa Cruz; 2017. Available from: http://www.escholarship.org/uc/item/7744s04p

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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Open Access Theses and Dissertations