Five new steroids, the cholest-4-ene-3,22-diones : tumacone A (1), tumacone B (2), tumacoside A (3), tumacoside B (4), and a furostenone: tumaquenone (5), besides diosgenone (6), were isolated from the aerial parts of Solanum nudum. Their structures were determined by 2D NMR, MS analyses and chemical correlations. Steroid 3 and 5 displayed in vitro antimalarial activity against a Plasmodium falciparum chloroquine-resistant FCB-1 strain (IC50 27 and 16 mu M). The observed stereodependent cyclization into spiroketals of two 16-O isomers is discussed.
antimalarial, steroids, Solanum nudum, cholest-4-en-3, 22-dione, tumacones A and B, tumacosides A and B, tumaquenone, stereodependent cyclization
Publication DOI: 10.1016/S0040-4039(98)01354-9Journal NLM ID: 2984819RPublisher: Elsevier
Institutions: State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
Methods: 13C NMR, 1H NMR, EI-MS, IR, optical rotation measurement, CC, NOESY, HR-FAB-MS, extraciton
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