Masaru Ogura

Anticancer sesquiterpene lactones of Michelia compressa (magnoliaceae)

Abstract Investigation of the cytotoxic active components of Michelia compressa afforded two new cytotoxic sesquiterpene lactones, michelenolide and micheliolide. Parthenolide, costunolide, santamarine, reynosin and liriodenine were also isolated and exhibited cytotoxic activity. The known sesquiterpene lactones, lanuginolide and dihydroparthenolide, were isolated but were not active. Two other new inactive sesquiterpene lactones, compressanolide and dihydroreynosin, were also obtained. The structures of michelenolide and micheliolide were confirmed by partial synthesis from parthenolide and the structure of compressanolide by partial synthesis from dihydroparthenolide.

3S,24S,25-Trihydroxytirucall-7-ene from Ailanthus excelsa

Abstract A new triterpene has been isolated from the root bark of Ailanthus excelsa (Simaroubaceae) and identified as 3S,24S,25-trihydroxytirucall-7-ene.

Periandrin II and IV, triterpene glycosides from Periandra dulcis

Abstract Investigation of the natural sweeteners of Periandra dulcis afforded new sweet triterpene glycosides, periandrin II (3-β- O -[β- d -glucuronopyranosyl-(1→-2)-β- d -glucuronopyranosyl]-25-formyl-olean-12(13)-en-30-oic acid) and periandrin IV (3-β- O -[β- d -glucuronopyranosyl-(1→2)-β- d -glucuronopyranosyl]-25-hydroxyolean-12(13)-en-30-oic acid). Evidence for the structures was obtained by correlation of their derivatives with known compounds.

Jacoumaric acid, a new triterpene ester from Jacaranda caucana

Abstract Jacoumaric acid isolated from Jacaranda caucana is shown to be 2α-hydroxy-3β- trans-p -coumaryloxy-urs-12-en-28-oic acid.

Periandrin III, a novel sweet triterpene glycoside from Periandra dulcis

Abstract Periandrin III, a new sweet triterpene glycoside of the roots of Pepiandra dulcis, has been shown to possess the structure 3-β-O-[β- d -g