Resveratrol 3-O-beta-D-glucopyranoside (1) has been isolated from the seeds of Erythrophleum lasianthum (Caesalpinioidae, Leguminosae), a South African plant used in traditional medicine, and has shown antiplatelet aggregation activity. The synthesis of 1, related hydroxystilbenes, and their glucosides has been undertaken to provide larger quantities, for further biological evaluation, and has been accomplished via Wittig reactions followed by glucosylation under phase transfer catalysis.

The characterisation of a further novel 1 a-hydroxycycloartane glycoside, mollic acid 3-p-~-xyloside, and of its genuine aglycone mollic acid is reported. Three new hydrolysis artifacts of the aglycone have been prepared and 13C .n.m.r. spectral data for these compounds are tabulated.We previously reported the isolation of mollic acid glucoside (1) a 1 ~-hydroxycycloart-24-en-30-oic acid 3-P-~-glucoside isolated from the acetone extract of Combretum molle leaves and showed that the acid hydrolysis of compound (1) in tetrahydrofuran (THF) gave the rearranged anhydro aglycone artifact (8).Subsequent investigations have led to the isolation of mollic acid (3), the genuine aglycone of (l), plus the related compound

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Two alkaloids 1 and 2 were isolated from the seeds of Erythrophleum lasianthum. Their structures were assigned by spectroscopic and chemical means as 3 beta-hydroxynorerythrosuamine (1) and its 3-O-beta-D-glucopyranoside (2). In spontaneously beating atria, both compounds 1 and 2 showed a marked and concentration-dependent positive inotropic activity and a weak negative chronotropic activity. The positive inotropic effect induced by 1 and 2 was not modified by propranolol, prazosin, carbachol, and ranitidine plus pyrilamine. Both 1 and 2 were very active in inhibiting the Na+/K(+)-ATPase isolated from bovine cardiac sarcolemmal vesicles.

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