""Of molecules and men"" : inaugural lecture delivered at Rhodes University
- Authors: Kaye, Perry T
- Date: 1989
- Subjects: Biochemistry , Chemistry, Organic , Chemistry
- Language: English
- Type: Text
- Identifier: vital:643 , http://hdl.handle.net/10962/d1020712 , ISBN 0868101842
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
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- Date Issued: 1989
Crystallographic Analysis and Structural Revision of a Spiroterpenoid Rearrangement Product
- Authors: Lobb, Kevin A , Kaye, Perry T
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449335 , vital:74812 , xlink:href="https://www.ajol.info/index.php/sajc/article/view/122435"
- Description: Single crystal X-ray analysis of a spiroterpenoid rearrangement product has revealed that its structure is, in fact, isomeric with the structure proposed previously – an observation that has significant mechanistic implications.
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- Date Issued: 2003
100 years of chemistry at Rhodes University
- Authors: Brown, Michael E , Eve, Desmond John , Kaye, Perry T , Rivett, Douglas E A , Watkins, Gareth M
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6564 , http://hdl.handle.net/10962/d1004123
- Description: The history of Grahamstown is well documented and two books deal with the history of Rhodes University.1,2 Although the Chemistry Department was one of the founding departments, coverage in the official histories is minimal and sometimes inaccurate or misleading. The Rhodes University Centenary is an appropriate time to look back on some of the achievements of the department and some of its graduates over the past 100 years.
- Full Text:
- Date Issued: 2004
The Baylis-Hillman entrée to heterocyclic systems — the Rhodes contribution
- Authors: Kaye, Perry T
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6575 , http://hdl.handle.net/10962/d1004138
- Description: This review focuses on applications of the Baylis-Hillman reaction in the synthesis of various heterocyclic products, which include indolizines, chromenes, thiochromenes, coumarins and quinolines. Attention is also given to the mechanistic implications and the elaboration of various products to afford compounds with medicinal potential.
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- Date Issued: 2004
Synthesis and structure determination of 8-and 9-iodocamphorquinone bis (ethylene ketal)
- Authors: Magqi, Nceba , Lobb, Kevin A , Kaye, Perry T , Caira, Mino R
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449399 , vital:74817 , xlink:href="https://doi.org/10.3184/030823407X209"
- Description: The structures of 8- and 9-iodocamphorquinone bis(ethylene ketal) have been confirmed by spectroscopic and single crystal X-ray analysis. The unexpected formation of the latter isomer is attributed to intramolecular rearrangement of the camphor skeleton, the mechanistic details of which have been explored using coset analysis.
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- Date Issued: 2007
Chromone Studies. Part 17. Tricyclic Scaffolds from Reactions of chromone-3-carbaldehydes and methyl vinyl ketone under Baylis–Hillman conditions
- Authors: Ganto, Mlungiseleli M , Molefe, Duduzile M , Lobb, Kevin A , Kaye, Perry T
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449321 , vital:74811 , xlink:href="https://doi.org/10.3184/030823409X4652"
- Description: Reaction of a series of chromone-3-carbaldehydes with methyl vinyl ketone under Baylis–Hillman conditions, using 3-hydroxyquinuclidine in chloroform or DABCO in 1-methyl-2-pyrrolidinone, affords unprecedented tricylic chromone derivatives which, depending on the conditions, may be accompanied by the normal Baylis–Hillman products or their respective tricyclic dimers.
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- Date Issued: 2009
31P NMR kinetic study of the tandem cleavage of phosphonate esters by bromotrimethylsilane
- Authors: Conibear, Anne C , Lobb, Kevin A , Kaye, Perry T
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449304 , vital:74810 , xlink:href="https://doi.org/10.1016/j.tet.2010.08.058"
- Description: 1H and 31P NMR methods have been used to access rate constants and activation parameters for each of the consecutive second-order silylation reactions involved in the overall transformation (1a→3a→4a), while computational optimisation of the rate constants obtained from the initial, linear phase of each reaction has permitted an excellent fit with the experimental data for the entire course of the reaction.
- Full Text:
- Date Issued: 2010
Introducing chemistry students to the “real world” of chemistry
- Authors: Brown, Michael E , Cosser, Ronald C , Davies-Coleman, Michael T , Kaye, Perry T , Klein, Rosalyn , Lamprecht, Emmanuel , Lobb, Kevin A , Nyokong, Tebello , Sewry, Joyce D , Tshentu, Zenixole R , Van der Zeyde, Tino , Watkins, Gareth M
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449360 , vital:74814 , xlink:href="https://doi.org/10.1021/ed8001539"
- Description: A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at second-year level with practical projects in which student teams formulate and prepare relatively simple chemical products for marketing, followed a year later by a more advanced study of the feasibility of producing and marketing a fine chemical on a commercial scale.
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- Date Issued: 2010
Towards the synthesis of coumarin derivatives as potential dual-action HIV-1 protease and reverse transcriptase inhibitors
- Authors: Olomola, Temitope O , Klein, Rosalyn , Lobb, Kevin A , Sayed, Yasien , Kaye, Perry T
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448963 , vital:74774 , xlink:href="https://doi.org/10.1016/j.tetlet.2010.09.121"
- Description: 3-(Chloromethyl)coumarins, obtained via acid-catalysed cyclisation of salicylaldehyde-derived Baylis– Hillman adducts, have been treated with propargylamine; reaction of the resulting 3-alkynylmethylcoumarins with azidothymidine (AZT) in the presence of a Cu(I) catalyst has afforded a series of cycloaddition products for evaluation, in their own right, as potential dual-action HIV-1 protease and non-nucleoside reverse transcriptase inhibitors, and as scaffolds for further structural elaboration.
- Full Text:
- Date Issued: 2010
1H NMR-based kinetic and mechanistic study of unusual skeletal rearrangements of a spirobornyl tosylate derivative
- Authors: Lobb, Kevin A , Kaye, Perry T
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448858 , vital:74766 , xlink:href="https://doi.org/10.1002/poc.1699"
- Description: 1H NMR analysis of the kinetics of skeletal rearrangement of optically pure 3,3-xylyl-2-exo-bornyl tosylate in CDCl3 indicates the operation of tandem autocatalytic and pseudo-first-order transformations, leading sequentially to a pairof isomeric camphene derivatives and involving partial racemization. Changing the solvent system has been shown topermit the chemoselective isolation of either of the isomeric camphenes.
- Full Text:
- Date Issued: 2011
Designer ligands : the search for metal ion selectivity
- Authors: Kaye, Perry T
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6576 , http://hdl.handle.net/10962/d1004139
- Description: The paper reviews research conducted at Rhodes University towards the development of metal-selective ligands. The research has focused on the rational design, synthesis and evaluation of novel ligands for use in the formation of copper complexes as biomimetic models of the metalloenzyme, tyrosinase, and for the selective extraction of silver, nickel and platinum group metal ions in the presence of contaminating metal ions. Attention has also been given to the development of efficient, metal-selective molecular imprinted polymers.
- Full Text:
- Date Issued: 2011
Synthesis and evaluation of phosphonated N-heteroarylcarboxamides as DOXP-reductoisomerase (DXR) inhibitors
- Authors: Bodill, Taryn , Conibear, Anne C , Blatch, Gregory L , Lobb, Kevin A , Kaye, Perry T
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448939 , vital:74772 , xlink:href="https://doi.org/10.1016/j.bmc.2010.11.062"
- Description: The diethyl esters and disodium salts of a range of heteroarylcarbamoylphosphonic acids have been prepared and evaluated as analogues of the highly active DOXP-reductoisomerase (DXR) inhibitor, fosmidomycin. Computer-simulated docking studies, Saturation Transfer Difference (STD) NMR analysis and enzyme inhibition assays have been used to explore enzyme-binding and -inhibition potential, while in silico analysis of the DXR active site has highlighted the importance of including a well-parameterised metal co-factor in docking studies and has revealed the availability of an additional binding pocket to guide future drug design.
- Full Text:
- Date Issued: 2011
DBU-Mediated cleavage of aryl-and heteroaryl disulfides
- Authors: Nyoni, Dubekile , Lobb, Kevin A , Kaye, Perry T , Cairab, Mino R
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448884 , vital:74768
- Description: The capacity of the nitrogen nucleophile, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to reduce aryl- and heteroaryl disulfides to the corresponding mercaptans is demonstrated. While dicarboxylated disulfide analogues afford the mono-DBU disulfide salts, as confirmed by X-ray crystallography, the corresponding methyl esters are cleaved normally.
- Full Text:
- Date Issued: 2012
1H NMR-based kinetic-mechanistic study of the intramolecular trans-esterification of 2-exo-3-exo-dihydroxybornane monoacrylate esters
- Authors: Duggan, Andrew R , Mciteka, Lulama P , Lobb, Kevin A , Kaye, Perry T
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448871 , vital:74767 , xlink:href="https://hdl.handle.net/10520/EJC135616"
- Description: A 1H NMR study of the acid-catalyzed, intramolecular trans-esterification between isomeric 2-exo-3-exo-dihydroxybornane monoacrylate esters has afforded insights into the reaction mechanism and permitted the determination of kinetic and thermodynamic parameters for the pseudo-first-order processes.
- Full Text:
- Date Issued: 2013
Dual-Catalyst Acceleration of Tandem Disulfide Cleavage and Baylis–Hillman Synthesis of 2 H-1-Benzothiopyran Derivatives
- Authors: Nyoni, Dubekile , Lobb, Kevin A , Kaye, Perry T
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448898 , vital:74769 , xlink:href="https://doi.org/10.1080/00397911.2012.673449"
- Description: While both 1,8-diazabicyclo[5.4.0]undec-7-ene and triphenylphosphine catalyze tandem Baylis–Hillman reaction/disulfide cleavage of 2,2′-dithiodibenzaldehyde independently, when used together as a dual-catalyst system, the overall yields of the cyclized 2H-1-benzothiopyrans are consistently greater and the reaction time decreases dramatically.
- Full Text:
- Date Issued: 2013
Exploring DOXP-reductoisomerase binding limits using phosphonated N-aryl and N-heteroarylcarboxamides as DXR inhibitors
- Authors: Bodill, Taryn , Conibear, Anne C , Mutorwa, Marius K , Goble, Jessica L , Blatch, Gregory L , Lobb, Kevin A , Klein, Rosalyn , Kaye, Perry T
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448912 , vital:74770 , xlink:href=""
- Description: DOXP-reductoisomerase (DXR) is a validated target for the development of antimalarial drugs to address the increase in resistant strains of Plasmodium falciparum. Series of aryl- and heteroarylcarbamoylphosphonic acids, their diethyl esters and disodium salts have been prepared as analogues of the potent DXR inhibitor fosmidomycin. The effects of the carboxamide N-substituents and the length of the methylene linker have been explored using in silico docking studies, saturation transfer difference NMR spectroscopy and enzyme inhibition assays using both EcDXR and PfDXR. These studies indicate an optimal linker length of two methylene units and have confirmed the importance of an additional binding pocket in the PfDXR active site. Insights into the constraints of the PfDXR binding site provide additional scope for the rational design of DXR inhibitors with increased ligand–receptor interactions.
- Full Text:
- Date Issued: 2013
Application of Baylis-Hillman methodology in the direct construction of chromone derivatives
- Authors: Faridoon, H , Olomola, Temitope O , Klein, Rosalyn , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442488 , vital:73992 , https://doi.org/10.1016/j.tet.2015.11.039
- Description: Pyridinium chlorochromate oxidation of Baylis-Hillman-derived tert-butyl 2H-chromene-3-carboxylates affords chromone-3-carboxylate esters, providing the first application of Baylis-Hillman methodology in a direct and convenient three-step synthesis of chromone derivatives.
- Full Text:
- Date Issued: 2016
Elucidating Latent Mechanistic Complexity in Competing Acid-Catalyzed Reactions of Salicylaldehyde-Derived Baylis–Hillman Adducts
- Authors: Olomola, Temitope O , Klein, Rosalyn , Caira, Mino, R , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442596 , vital:74010 , https://doi.org/10.1021/acs.joc.5b02372
- Description: 1H NMR-based kinetic studies have revealed the latent mechanistic complexity of deceptively simple hydrochloric acid-catalyzed reactions of salicylaldehyde-derived Baylis–Hillman adducts. Reactions conducted at 0 °C afforded 2-(chloromethyl)cinnamic acid derivatives as the major products and the corresponding 3-(chloromethyl)coumarin derivatives as the minor products. In reactions conducted in refluxing acetic acid, however, the 3-(chloromethyl)coumarin derivatives are the sole products. Variable-temperature 1H NMR analysis permitted the determination of the rate constants and kinetic parameters involved in the pseudo-first-order formation of (Z)-2-(chloromethyl)-3-(2-hydroxyphenyl)-2-propenoic acid. The kinetic data clearly preclude the operation of classical kinetic versus thermodynamic control and indicate the operation of three independent reaction pathways. Theoretical studies of these pathways undertaken at the B3LYP/6-31G(d) level permitted rationalization of the experimental data and provided insights into the possible mechanism of the enzymic E–Z isomerization and cyclization of (E)-cinnamic acid analogues to afford coumarins.
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- Date Issued: 2016
Supplementary Material Synthesis and biological evaluation of (E)-cinnamic acid,(E)-2-styrylthiazole and (E)-2-[2-(naphthalen-1-yl) vinyl] thiazole derivatives
- Authors: Olawode, Emmanuel O , Tandlich, Roman , Prinsloo, Earl , Isaacs, Michelle , Hoppe, Heinrich C , Seldon, Ronnett , Warner, Digby F , Steenkamp, Vanessa , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431778 , vital:72803 , xlink:href=" https://www.arkat-usa.org/get-file/59868/"
- Description: The screening was conducted using multi-well plates which are suited for HeLa cells in the log phase of growth with final cell density > 10 cells/cm. Each experiment normally includes a blank control, containing medium without the cells.28,45 Non-contaminated HeLa cells (6.57 x 105 cells per well) in media were allowed to grow in the incubator under an atmosphere of 5% CO2 at 37 0C for 24 h. To each well was dispensed 200 µL of HeLa culture, containing 6.57 x 105 cells under LabEAir laminar flow hood (Vivid Air, South Africa); 20 µL of resazurin dye (Sigma TOX-8) and test compound (50 µL) were added, which were then incubated in the presence of 5% CO2 at 37 0C for 24 hours in a shaker, to enhance the distribution of the dye. The absorbance of each well was measured with Bio-tek Power Wave X fluorometer (Beijing, China), and increases in fluorescence was monitored at a wavelength of 590 nm, using an excitation wavelength of 560 nm.
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- Date Issued: 2016
Synthesis and evaluation of substituted 4-(N-benzylamino)cinnamate esters as potential anti-cancer agents and HIV-1 integrase inhibitors
- Authors: Faridoon, H , Edkins, Adrienne L , Isaacs, Michelle , Mnkandhla, Dumisani , Hoppe, Heinrich C , Kaye, Perry T
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66289 , vital:28929 , https://doi.org/10.1016/j.bmcl.2016.05.023
- Description: publisher version , Encouraging selectivity and low micromolar activity against HeLa cervical carcinoma (IC50 ⩾ 3.0 μM) and the aggressive MDA-MB-231 triple negative breast carcinoma (IC50 ⩾ 9.6 μM) cell lines has been exhibited by a number of readily accessible 4-(N-benzylamino)cinnamate esters. The potential of the ligands as HIV-1 integrase inhibitors has also been examined.
- Full Text: false
- Date Issued: 2016