Two new triterpenes from Alstonia scholaris flowers.
In the context of our previous communication on phytochemical studies of the ethanolic extract of flowers of Alstonia scholaris of Pakistan origin, these have resulted in the isolation of two new triterpenoids. One is of the oleanane type, alstoprenyol, 3-β-hydroxy-28-β-acetoxy-5-olea triterpene (1), the other is of ursane type, alstoprenylene 3β-acetate-24-nor-urs-4,12,2'-triene ester triterpene (2) and together with four known triterpenes, α-amyrin acetate (3), α-amyrin (4), lupeol acetate (5) and 3β-hydroxy-24-nor-urs-4,12,28-triene triterpene (6) were isolated. The structures of 1-6 were elucidated with the aid of extensive NMR spectroscopic studies.
Pharmaceutical Research Center, PCSIR Laboratories Complex, Karachi 75280, Pakistan. nighat2001us@hotmail.com
Nighat
N
Sultana
Zafar Saeed
ZS
Saify
Muhammad
M
Saleem
Mustafa
M
Kamal
D031051:Alstonia / Q000737:chemistry*; D002855:Chromatography, Thin Layer; D000431:Ethanol; D035264:Flowers / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010154:Pakistan; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification*
D010936:Plant Extracts; D014315:Triterpenes; D000431:Ethanol