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Withanolide Z, a new chlorinated withanolide from Withania somnifera
Swapan Pramanick1, Amit Roy, Shekher Ghosh
1Medicinal Chemistry Division, Indian Institute of Chemical Biology, Jadavpur, Kolkata, India.
Abstract:
Reverse-phase preparative HPLC analysis of the n-butanol fraction of the methanolic extract of Withania somnifera Dunal (leaves) afforded a novel chlorinated withanolide, namely withanolide Z (1), along with four known withanolides, withanolide B (2), withanolide A (3), 27-hydroxywithanolide B (4) and withaferin A (5). Their structures were elucidated by IR, MS, CD and a combination of 1 D and 2 D NMR spectral analyses. The Leishmania donovani DNA topoisomerase I inhibitory activities of the isolated compounds were determined.
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