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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Synthesis Of Reaction-Ready 6,6 '-Biindole And 6,6 '-Biisatin Via Palladium(Ii)-Catalysed Intramolecular C-H Functionalisation, Allan B. Gamble, Paul A. Keller
Synthesis Of Reaction-Ready 6,6 '-Biindole And 6,6 '-Biisatin Via Palladium(Ii)-Catalysed Intramolecular C-H Functionalisation, Allan B. Gamble, Paul A. Keller
Paul Keller
The first synthesis of a 6,6'-biindole and 6,6'-biisatin scaffold is reported with the penultimate step being the formation of the di-heterocyclic ring by Pd(II)-catalysed intramolecular C-H functionalisation and Sandmeyer cyclisation, respectively.
The First Syntheses Of Enantiopure 2,2 '-Biindoline, Steven M. Wales, Anthony C. Willis, Paul A. Keller
The First Syntheses Of Enantiopure 2,2 '-Biindoline, Steven M. Wales, Anthony C. Willis, Paul A. Keller
Paul Keller
The first two syntheses of chiral 2,2'-biindoline are reported either in five steps from 2,2'-bioxirane, or three steps from 2,2'-biaziridine, both with exceptional enantiopurity
Reductive Ring Opening Reactions Of Diphenyldihydrofullerenylpyrroles, William Hawkins, Paul A. Keller, Stephen G. Pyne
Reductive Ring Opening Reactions Of Diphenyldihydrofullerenylpyrroles, William Hawkins, Paul A. Keller, Stephen G. Pyne
Paul Keller
The reductive ring opening reaction conditions for the simple [60]fullerenyldihydropyrrole 1 have been optimized to include acetic acid in the reaction mixture to rapidly protonate the anionic intermediate. Under these conditions, the ring opened dihydrofullerene 2 was obtained in 68% yield. Under slightly modified conditions and at −78 °C, the reductive bis-ring opening of the tethered trans-4 isomer 3 provided the novel racemic bis-dihydrofullerenyl derivative 7.
Revealing Indigenous Indonesian Traditional Medicine: Anti-Infective Agents, Paul A. Keller, Ari Satia Nugraha
Revealing Indigenous Indonesian Traditional Medicine: Anti-Infective Agents, Paul A. Keller, Ari Satia Nugraha
Paul Keller
Indonesia is rich in medicinal plants which the population has used traditionally from generation to generation for curing diseases. Our interest in the treatment of infectious diseases has lead to the investigation of traditional Indonesian treatments. In this review, we present a comprehensive review of ethnopharmacologically directed screening in Indonesian medicinal plants to search for new anti-viral, antimalarial, anti-bacterial and anti-fungal agents. Some potent drug leads have been isolated from Indonesian medicinal plants. Further research is still required for the lead development as well as the search for new bioactive compounds from the enormous medicinal plant resources.
Binaphthyl-Anchored Antibacterial Tripeptide Derivatives With Hydrophobic C-Terminal Amino Acid Variations, John Bremner, Paul A. Keller, Stephen Pyne, Mark Robertson, Kandasamy Sakthivel, Kittiya Somphol, Dean Baylis, Jonathon A Coates, John Deadman, Dharshini Jeevarajah, David I. Rhodes
Binaphthyl-Anchored Antibacterial Tripeptide Derivatives With Hydrophobic C-Terminal Amino Acid Variations, John Bremner, Paul A. Keller, Stephen Pyne, Mark Robertson, Kandasamy Sakthivel, Kittiya Somphol, Dean Baylis, Jonathon A Coates, John Deadman, Dharshini Jeevarajah, David I. Rhodes
Paul Keller
The facile synthesis of seven new dicationic tripeptide benzyl ester derivatives, with hydrophobic group variations in the C-terminal amino acid component, is described. Moderate to good activity was seen against Gram-positive bacteria in vitro. One cyclohexyl-substituted compound 2c was tested more widely and showed good potency (MIC values ranging from 2–4 μg/mL) against antibiotic-resistant strains of Staphylococcus aureus and Enterococci (VRE, VSE), and against Staphylococcus epidermidis.
Synthesis Of Novel N-Protected Hydrophobic Phenylalanines And Their Application In Potential Antibacterials, Timothy P. Boyle, J. B. Bremner, Jonathan A. Coates, John Deadman, Paul A. Keller, Stephen G. Pyne, Kittiya Somphol
Synthesis Of Novel N-Protected Hydrophobic Phenylalanines And Their Application In Potential Antibacterials, Timothy P. Boyle, J. B. Bremner, Jonathan A. Coates, John Deadman, Paul A. Keller, Stephen G. Pyne, Kittiya Somphol
Paul Keller
An efficient synthesis of two new N-acetyl-4’-arylphenylalanines is described together with their incorporation in to a number of cationic peptoid antibacterial agents, one of which had an MIC of 7.8 μg/mL against Staphylococcus aureus.
Phytochemical And Biological Activity Studies Of The Bhutanese Medicinal Plant Corydalis Crispa, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Thanapat Sastraruji, Malai Taweechotipatr, Roonglawan Rattanajak, Aunchalee Tonsomboon, Sumalee Kamchonwongpaisan
Phytochemical And Biological Activity Studies Of The Bhutanese Medicinal Plant Corydalis Crispa, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Thanapat Sastraruji, Malai Taweechotipatr, Roonglawan Rattanajak, Aunchalee Tonsomboon, Sumalee Kamchonwongpaisan
Paul Keller
The chemical constituents and biological activities of Corydalis crispa (Fumariaceae) were investigated for the first time. The phytochemical study resulted in the isolation of nine known isoquinoline alkaloids: protopine (1), 13-oxoprotopine (2), 13-oxocryptopine (3), stylopine (4), coreximine (5), rheagenine (6), ochrobirine (7), sibiricine (8) and bicuculline (9), with complete NMR data for 2 and 3 provided here for the first time. Crude extracts exhibitedsignificant anti-inflammatory (p < 0.01) activity against TNF-alpha production in LPS activated THP-1 cells. The acetylcholinesterase inhibitory activity of compounds 2, 4 and 7 and the antiplasmodial activity of compound 5 against P. falciparum strains TM4/8.2 and K1CB1 …
Antimalarial Alkaloids From A Bhutanese Traditional Medicinal Plant Corydalis Dubia, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Anthony C. Willis, Sumalee Kamchonwongpaisan
Antimalarial Alkaloids From A Bhutanese Traditional Medicinal Plant Corydalis Dubia, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Anthony C. Willis, Sumalee Kamchonwongpaisan
Paul Keller
Ethnopharmacological relevance: Corydalis dubia is used in Bhutanese traditional medicine as a febrifuge and for treating infections in the blood, liver and bile which correlate to the signs and symptoms of malarial and microbial infections. Aim of the study: To validate the ethnopharmacological uses of the plant and to discover potential new therapeutic drug leads. Materials and methods C. dubia was collected from Bhutan and the alkaloids were obtained using acid–base fractionation and separation by repeated column and preparative plate chromatography. The alkaloids were identified from analysis of their physiochemical and spectroscopic data and were tested for antiplasmodial, antimicrobial and …
Structural Re-Assignment Of The Mono- And Bis-Addition Products From The Addition Reactions Of N-(Diphenylmethylene)Glycinate Esters To [60]Fullerene Under Bingel Conditions, Graham E Ball, Glenn Ashley Burley, Leila Chaker, William Hawkins, James Williams, Paul A. Keller, Stephen G. Pyne
Structural Re-Assignment Of The Mono- And Bis-Addition Products From The Addition Reactions Of N-(Diphenylmethylene)Glycinate Esters To [60]Fullerene Under Bingel Conditions, Graham E Ball, Glenn Ashley Burley, Leila Chaker, William Hawkins, James Williams, Paul A. Keller, Stephen G. Pyne
Paul Keller
The addition of N-(diphenylmethylene)glycinate esters (Ph2C=NCH2CO2R) to [60]fullerene under Bingel conditions gives [60]fullerenyldihydropyrroles and not methano[60]fullerenyl iminoesters [C60C(CO2R)(N=CPh2)] as previously reported. Unequivocal evidence for the structure of C60C(CO2Et)(N=CPh2) was provided by INADEQUATE NMR studies on 13C enriched material. New mechanistic details are proposed to account for the formation of [60]fullerenyldihydropyrroles and their reductive ring-opening reactions.