Structure and relative stereochemistry of a new polycyclic alkaloid, asparagamine A, showing anti-oxytocin activity, isolated from Asparagus racemosus

Abstract

The relative stereochemistry of a new cage-type alkaloid, asparagamine A 1, isolated from the roots of Asparagus racemosus Willd. (Liliaceae), has been elucidated by spectroscopic, chemical and single-crystal X-ray analyses. This novel polycyclic pyrrolizidine derivative is both the first alkaloid to be isolated from this genus and also the first pyrrolizidine derivative with carbon substituents at C-5 and C-8. The compound showed anti-oxytocin activity in vitro in a dose of 10^–5–10^–6 mg cm^–3.