Arun Sethi

Expedient synthesis of some novel pregnane derivatives and their evaluation as anti-oxidant and anti-dyslipidemic agents

Synthesis of a number of novel pregnane derivatives has been described in detail. They were prepared by reaction of 3β-hydroxy-5, 16-pregnadiene-20-one (2) with diethylene glycol, 2-methoxy ethanol, 1,2-propane diol, p-chloroaniline and p-fluoroaniline, respectively. The structures of these newly synthesized compounds have been established on basis of physical, analytical and spectral data. These pregnane derivatives have been evaluated for their anti-dyslipidemic activity (Triton model) and in vitro antioxidant activities. Out of the 12 compounds tested, 3 of them showed potent anti-dyslipidemic activity and 7 showed potent antioxidant and scavenger of oxygen free radicals.

Pregnane glycoside from Hemidesmus indicus as a potential anti-oxidant and anti-dyslipidemic agent

A new pregnane glycoside hindicusine (1) was isolated from the CHCl3–EtOH (3 : 2) extract of Hemidesmus indicus, whose structure was established on the basis of spectroscopic studies. The glycoside (1) and its acetylated derivative (5) were evaluated for their anti-oxidant and anti-dyslipidemic activities.

A new pregnane glycoside from Marsdenia roylei as potential antioxidant and antidyslipidemic agents

A new pregnane glycoside roylenine (1) was isolated from the CHCl3–EtOH (4:1) extract of Marsdenia roylei. Its structure was established on the basis of spectroscopic studies. The glycoside (1) and its acetylated derivative (6) were evaluated for their antioxidant and antidyslipidemic activities.

Synthesis, characterization, and biological evaluation of novel thiazole and pyrazole derivatives of quinoline-4-carboxylic acid as potential antimicrobial agents

A series of quinoline-based heterocycles prepared and bioevaluated for their possible antimicrobial activity against a panel of gram-positive bacteria [Staphylococcus aureus (ATCC-9144) and Bacillus subtilis (ATCC-6633)] and gram-negative bacteria [Pseudomonas aeruginosa (ATCC-25615), and Escherichia coli (MTCC-739)], and fungal strains [Candida albicans (ATCC-24433), Aspergillus niger (MTCC-872), and Aspergillus fumigatus (MTCC-343)] by the known methods. All the prepared quinoline derivatives have shown significant antimicrobial activities. Few compounds, viz. 4b, 4c and 4a, 4c proved to be active at low concentrations against Sa and Ca, respectively, while compounds 4a, 6d, and 6b showed milder inhibitory effects against other microbes. The structures of newly synthesized compounds were characterized by elemental analysis, Infrared (IR), 1HNMR, 13C-NMR and Mass-spectroscopy.

Design, synthesis and antimicrobial properties of novel 3,3a,4,5,6,7- hexahydroindazole and arylthiazolylpyrazoline derivatives.

A remarkable diastereoselective synthesis of some novel arylthiazolyl pyrazoline derivatives 3(a-l) is displayed which were evaluated for their in vitro antimicrobial activities. In particular, compounds 3e, 3g & 3l (MIC 12.5 μg /ml) showed good activity against S. aureus and compounds 3b & 3j (MIC 12.5 μg / ml) against B. subtilis. Compounds 3g, 3i, 3j (MIC 12.5 μg/ ml) and 3l (MIC 6.25 μg / ml) also displayed excellent antifungal activity against C. albicans. Of all the synthesized compounds, 3g and 3e exerted a wide range of antibacterial activities against entire tested gram positive (S. aureus and B. subtilis) and gram negative (E. coli and P. aeruginosa) bacterial strain except P. aeruginosa.