Infraspecific variation of sulfur-containing bisamides from Aglaia leptantha.

Six new amides, leptaglin (1), hemileptaglin (2), aglanthin (3), agleptin (4), isoagleptin (5), and leptanthin (6), together with known lignans yangambin, eudesmin, grandisin (7), epigrandisin (8), and dehydrodiconiferyl alcohol, were isolated and identified from the lipophilic leaf and stem bark extracts of Aglaia leptantha. The dominating sulfur-containing bisamides contained either putrescine or the corresponding pyrrolidine ring as the diamine part, linked to phenylacetic and/or methylthiopropenoic acid moieties showing a remarkable infraspecific variation in eight individuals from two different habitats. Structures were determined by MS and NMR, including lanthanide-induced shifts.