Bio-guided isolation of androsta-1,4-dien-3,16-dione as a vasodilator active principle from the inflorescence of Sonn. (Strelitziaceae).

Androsta-1,4-dien-3,16-dione was isolated for the first time from the plant kingdom of the ethanolic extract of the ' inflorescence by the bio-guided method. Its structure was elucidated by NMR and MS spectroscopic data analysis. The vascular effects of ethanol extracts, fractions and androsta-1,4-dien-3,16-dione were assessed on the phenylephrine pre-contracted isolated rat aorta.