Petuniasterones from Petunia parodii and P. integrifolia; unusual ergostane-type steroids

Abstract

From leaves of Petunia parodii were isolated four epoxy group-bearing petuniasterones. These were shown to be (22 R,24 R)-7α-acetoxy-4β,5β-epoxy-17β,22,24,25-tetrahydroxyergost-1-en-3-one 22,24,25-[(methylthio)carbonyl]orthoacetate (petuniasterone I); (22 R,24 R)-7α,12α-diacetoxy-4β,5β-epoxy-22,24,25-trihydroxyergost-1-en-3-one 22,24,25-orthoacetate (petuniasterone J); (22 R,24 R)-7α-acetoxy-16β,17β-epoxy-22,24,25-trihydroxyergosta-1,4-dien-3-one 22,24,25-orthoacetate (petuniasterone K); and (22 R,24 R)-7α-acetoxy-16β,17β-epoxy-22,24,25-trihydroxy-ergosta-1,4-dien-3-one 22,24,25-[(methylthio)carbonyl]orthoacetate (petuniasterone L). From leaves of Petunia integrifolia were isolated (22 R,24 R)-7α,12ξ-diacetoxy-11β,22,24,25-tetrahydroxyergosta-1,4-diene-3-one 22,24,25-orthoacetate (12ξ-acetoxy-11-β-hydroxypetuniasterone D 7-acetate); (22 R,24 R)-7α,12ξ-diacetoxy-11β,22,24,25-tetrahydroxyergosta-1,4-dien-3-one 22,24,25-orthopropionate (12ξ-acetoxy-11β-hydroxypetuniasterone M 7-acetate); (22 R,24 R)-7α,22,24,25-tetrahydroxyergosta-1,4-dien-3-one 22,24,25-orthopropionate (petuniasterone M); and (22 R, 24 R)-12α-acetoxy-7α,22,24,25-tetrahydroxyergosta-1,4-diene-3-one 22,24,25-orthopropionate (12α-acetoxypetuniasterone M). From leaves of Petunia hybrida were isolated 30-hydroxypetuniasterone A 7-acetate and petuniasterone C 7-acetate.