@article{
author = "Krstić, Natalija M. and Bjelaković, Mira S. and Pavlović, Vladimir D. and Robeyns, Koen and Juranić, Zorica D. and Matić, Ivana Z. and Novaković, Irena T. and Sladić, Dušan",
year = "2012",
abstract = "The reactions of 17 alpha-hydroxyprogesterone with Lawesson's reagent (LR) in toluene, CH2Cl2 and/or CCl4 gave, depending on the duration of the reaction, two diastereoisomeric androst-4-en-17-spiro-1,3,2-oxathiaphospholane-2-sulfide pairs 2a,b and 3a,b in approximately 7:3 ratio, differing in configuration at the phosphorus atom. A parallel analysis of heteronuclear 2D H-1-C-13 spectra (HSQC and HMBC) and homo-nuclear 2D spectra (NOESY) enabled complete H-1 and C-13 assignments of each isomer. Also, analysis of NOESY correlations provided evidence for the preferred conformation. X-ray analysis of 3a confirmed the structure and absolute configuration on phosphorus. A pathway for the formation of 1,3,2-oxathiaphospholane ring was proposed. Cytotoxic activity in vitro was tested against three tumor cell lines (human cervix carcinoma HeLa cells and two human breast carcinoma MDA-MB-361 and MDA-MB-453 cells). Compound 3a and mixture 3a,b showed a moderate activity against HeLa and MDA-MB-453 cell lines while against MDA-MB-361 cell line all tested compounds exerted very weak cytotoxic effect. Antimicrobial activity against Gram-positive, Gram-negative bacteria and fungal cells, toxicity to brine shrimp Artemia sauna, were evaluated. All tested compounds showed strong antifungal activity. (C) 2012 Elsevier Inc. All rights reserved.",
publisher = "Elsevier Science Inc, New York",
journal = "Steroids",
title = "New androst-4-en-17-spiro-1,3,2-oxathiaphospholanes. Synthesis, assignment of absolute configuration and in vitro cytotoxic and antimicrobial activities",
volume = "77",
number = "5",
pages = "558-565",
doi = "10.1016/j.steroids.2012.01.021"
}