(22Z,24S)-Stigmasta-5,22,25-trien-3β-ol and other novel sterols from Clerodendrum scandens: first report of the isolation of a cis-Δ²²-unsaturated sterol from a higher plant

Abstract

(22Z,24S)-Stigmasta-5,22,25-trien-3β-ol was isolated from Clerodendrum scandens(Verbenaceae). It is only the second example of a naturally occurring Z-Δ22-unsaturated sterol. Four other novel sterols were isolated from the same source, viz.(24S)-5α-stigmast-25-en-3β-ol, (22E,24S)-5α-stigmasta-22,25-dien-3β-ol, 24-methylergosta-5,25-dien-3β-ol, and (24S)-14α-methyl-5α-stigmasta-9(11),25-dien-3β-ol. All structures were determined by chemical and spectroscopic methods.