Results 191 to 200 of about 8,953 (240)

Synthesis of epimers of ampicillin

Pharmaceutical Chemistry Journal, 1968
1. The potassium salts of N-[1-methyl-2-ethoxycarbonylvinyl]-D(−)-, L(+)-, and DL-α-aminophenylacetic acids were synthesized and their physicochemical properties were studied. 2. From the N-substituted D(−)-, L(+)-, and DL-isomers of α-aminophenylacetic acid were synthesized epimers of ampicillin, and their physicochemical and ...
G. S. Postnikova, M. S. Rabinovich, P. S. Braginskaya   +2 more
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7-Hydroxydehydroepiandrosterone epimers in the life span

The Journal of Steroid Biochemistry and Molecular Biology, 2001
Evidence has been accumulated that 7-hydroxyepimers of dehydroepiandrosterone (7-OH-DHEA), may act as locally active immunomodulatory and immunoprotective agents, counteracting exaggerated actions of glucocorticoids. Since Skinner et al. (1977) developed the first unspecific RIA, it has been known that 7alpha-OH-DHEA is present in near nanomolar ...
R, Hampl, M, Hill, L, Stárka
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Antibacterial activity of resolved temocillin epimers

Journal of Antimicrobial Chemotherapy, 1986
The antibacterial activity of pure resolved R and S epimers of temocillin was determined in a variety of in-vitro test systems, including those that allowed measurement of activity during the early period following exposure to the agents, thus minimising the effect of epimerization.
A R, White, C E, Cooper, K E, Griffin, B, Slocombe   +3 more
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Electrophoresis of Glucose Epimers

Nature, 1957
THE movement of sugars in an electric field has already been used in certain analytical and preparative methods. This movement is based on the principle that borate ions form complexes with hydroxyl groups in sugars, so that these will move towards the anode in a borate buffer.
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Activity, Stability, and Pharmacology of the Epimers of Moxalactam

Clinical Infectious Diseases, 1982
By an agar-dilution procedure, the minimal inhibitory concentrations of R, S, and R + S epimers of moxalactam were determined for 23 commonly isolated organisms. Generally the R epimer was twice as active as the S epimer; however, against Pseudomonas aeruginosa the two were equally active. The stability of the epimers and of the R + S mixture in saline
R, Wise, N, Wright, P J, Wills
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Synthesis of Castanospermine and Epimers by Metathesis Routes

Current Organic Chemistry, 2013
This article provides a fairly comprehensive overview on olefin metathesis reactions applied as pivotal steps in the total syntheses of indolizidine alkaloids belonging to the families of castanospermine, deoxycastanospermine and diastereomers thereof, natural or non-natural compounds that play multiple roles in biological processes.
Dragutan, Ileana, Vosloo, Hermanus C.M., Dragutan, Valerian, Demonceau, Albert   +3 more
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The resolution of aglinin A epimers and their NMR assignments

Journal of Asian Natural Products Research, 2013
Aglinin A (1) is a mixture of C(24)-epimeric 20S,24-epoxy-24,25-dihydroxy-3,4-secodammar-4(28)-en-3-oic acid and present in plants of the family Meliaceae. The two epimers of 1 were resolved through an acetonide reaction, and the absolute configurations of two derivatives were deduced by the analysis of their (13)C NMR differences induced by γ-gauche ...
Tian-Xiang, Feng, Shi-Jin, Qu, Jun-Jie, Tan, Kun, Jiang, Chang-Heng, Tan, Shuang-Jun, Lin   +5 more
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Stereoselective synthesis of (+)-boronolide and its 8-epimer

Organic & Biomolecular Chemistry, 2004
Starting from readily available carbohydrates the synthesis of 8-epi-(+)-boronolide 19 and (+)-boronolide was achieved with diastereoselective propargylation of alpha-oxygenated aldehyde as a key step.
Shou-Gang, Hu, Tai-Shan, Hu, Yu-Lin, Wu
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Total synthesis of (±) commiphoranes C–D and their epimers

Organic & Biomolecular Chemistry, 2022
(±) Commiphorane C, (±) commiphorane D, and their two isomers were synthesized through a linear synthesis strategy in 14 steps.
Xiaoyu Liu, Haidong Deng, Yingjun Jiang, Yang Cao, Zhe Wang, Xiaozhen Jiao, Ping Xie   +6 more
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Synthesis of epimer of Taniaphos ligand

Journal of Organometallic Chemistry, 2016
Abstract The spatial arrangement of groups within a chiral ligand is essential for its catalytic performance. This work describes convenient synthesis of (R,Sp)-1-(2-(diphenylphosphano)ferrocenyl)-1-(2-diphenylphosphanophenyl)-N,N-dimethylmethanamine, a diastereomer of the well known (R,Rp)-Taniaphos ligand.
Ambroz Almássy, Erik Rakovský, Andrea Malastová, Zuzana Sorádová, Radovan Šebesta   +4 more
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