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The complete stereochemistry of the antibiotic candicidin A3 (syn. ascosin A3, levorin A3)
Julia Borzyszkowska-Bukowska1, Paweł Szczeblewski1, Agnieszka Konkol1
1Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdańsk University of Technology, Gdańsk, Poland.
Abstract:
Herein, the stereostructure of the aromatic heptaene macrolide (AHM) antifungal antibiotic candicidin A3 (syn. ascosin A3, levorin A3) has been established upon the 2D NMR studies, consisting of DQF-COSY, TOCSY, ROESY, HSQC and HMBC experiments, as well as upon extensive molecular dynamics simulations. The geometry of the heptaenic chromophore was defined as: (22E, 24E, 26Z, 28Z, 30E, 32E, 34E). The previously unreported absolute configuration of the chiral centres of candicidin A3 was established as: (3R, 9R, 11S, 13S, 15R, 17S, 18R, 19S, 21R, 36S, 37R, 38S, 40S, 41S).
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