Antiviral isoflavonoid sulfate and steroidal glycosides from the fruits of Solanum torvum

The C-4 sulfated isoflavonoid, torvanol A (1), and the steroidal glycoside, torvoside H (3), together with the known glycoside, torvoside A (2), were isolated from a MeOH extract of Solanum torvum fruits. Upon enzymatic hydrolysis with beta-glucosidase, torvoside A (2) and torvoside H (3) yielded the corresponding acetal derivatives 4 and 5, respectively. Torvanol A (1), torvoside H (3) and compound 5 exhibited antiviral activity (herpes simplex virus type 1) with IC50 values of 9.6. 23.2 and 17.4 mug/ml, respectively. Compounds 1-5 showed no cytotoxicity (at 50 mug/ml) against BC, KB and Vero cell lines. (C) 2002 Elsevier Science Ltd. All rights reserved.