Squamocin-O1 and squamocin-O2, new adjacent bis-tetrahydrofuran acetogenins from the seeds of Annona squamosa

Abstract

Two bis-tetrahydrofuran acetogenins, squamocin-O1 (1) and squamocin-O2 (2), were isolated from a MeOH extract of seeds of Annona squamosa L. Their structures were determined by spectral means including precursor-ion scanning mass spectral analysis for their aminal derivatives. The configurations at the oxymethine chiral centers were assigned as 12R, 15R, 16R, 19R, 20R, 23R, 24S, 28S, 36S for 1 and 12S, 15R, 16R, 19R, 20R, 23R, 24S, 28S, 36S for 2, based on 1H NMR analysis of their Mosher's ester derivatives and CD data, © 2002 Elsevier Science Ltd. All rights reserved.