Polyhydroxy cucurbitane triterpenes from Hemsleya penxianensis tubers

Triterpenes from Mimusops elengi.

Pentacyclic triterpenes (1) and (2) have been isolated from Mimusops elengi and assigned structures 3beta,6beta,19alpha,23-tetrahydroxy-urs-12-ene and 1beta-hydroxy-3beta-hexanoyllup-20 (29)-ene-23, 28-dioic acid, respectively, on the basis of spectroscopic studies including 2D-NMR. The compound 1 showed moderate inhibiting activity against beta-glucuronidase enzyme

Polycarbonates from the polyhydroxy natural product quinic acid.

Strategies for the preparation of polycarbonates, derived from natural polyhydroxy monomeric repeat units, were developed for biosourced polycarbonates based on quinic acid. The design and synthesis of regioselectively tert-butyldimethylsilyloxy (TBS)-protected 1,4- and 1,5-diol monomers of quinic acid were followed by optimization of their copolymerizations with phosgene, generated in situ fro...

New cucurbitane triterpenoids and steroidal glycoside from Momordica charantia.

Three new cucurbitane triterpenoids 1-3 and one new steroidal glycoside 4, were isolated together with ten known compounds from Momordica charantia. The structures of new compounds were determined to be 19(R)-n-butanoxy-5 beta,19-epoxycucurbita-6,23-diene-3beta,25-diol 3-O-beta-glucopyranoside (1), 23-O-beta-allopyranosylecucurbita-5,24-dien-7 alpha,3beta,22(R),23(S)-tetraol 3-O-beta-allopyrano...

triterpenes from euphorbia denticulata

Cucurbitane-type triterpenes with anti-proliferative effects on U937 cells from an egyptian natural medicine, Bryonia cretica: structures of new triterpene glycosides, bryoniaosides A and B.

The 90% aqueous ethanol extract of an Egyptian natural medicine, the roots of Bryonia cretica L., was found to exhibit a strong inhibitory effect on the proliferation of human leukemia U937 cells. By bioassay-guided fractionation, we isolated two new cucurbitane-type triterpene glycosides, bryoniaosides A and B, were isolated from the roots of Bryonia cretica L. together with 16 known cucurbita...