Petuniasterones. Part 2. Novel ergostane-type steroids from Petunia hybrida vilm. (solanaceae)

Abstract

Four new compounds in the petuniasterone series were isolated from leaves and stems of Petunia hybrida. These all possess the Δ^1,4-diene-3-one structure and have a 7α-oxygenated functionality. Compounds identified include the 17β-hydroxy derivative of petuniasterone A (9) and its 7-acetate (10) in addition to petuniasterone D (3), which is the orthoacetate of (22R,24R)-7α-22,24,25-tetrahydroxyergosta-1,4-dien-3-one as well as 12α-acetoxypetuniasterone D 7-acetate (5).