Two undescribed paradol-related specialized metabolites from Aframomum melegueta.

Aframomum melegueta seeds are widely used as a spice in Africa. Two undescribed paradol-related compounds, (S)-9-hydroxy-[6]-paradol (1) and (9S)-3,9-dihydroxydihydro-[6]-paradol (2) together with eight reported constituents (3-10) were isolated and characterised from the methanol extract of A. melegueta seeds. Structure elucidation of these metabolites was achieved by means of NMR and mass spectroscopic data analyses. The absolute configuration of undescribed compounds (1 and 2) was determined using the modified Mosher's method.