Tropane alkaloids from Erythroxylum zeylanicum OE Schulz (Erythroxylaceae)

Six tropane alkaloids were isolated from the Sri Lankan endemic plant Eryth roxylum zeylanicum O.E. Schulz (Erythroxylaceae) and structurally elucidate d by NR IR and MS measurements. Three of them, erythrozeylanines A [1R,3R,5 S,6R-6-acetoxy-3-(3 ',4' ,5 '-trimethoxybenzoyloxy)tropane], B [cis-3 beta- (cinnamoyloxy)tropane], and C [cis-6 beta-acetoxy-3 alpha-(cinnamoyloxy)tro pane] are new, whereas the others have already been found in other Erythrox ylum species. For the first time, the absolute configuration of a tropane a lkaloid (erythrozeylanine A) has been determined by quantum chemical CD cal culations. (C) 2000 Elsevier Science Ltd. All rights reserved.