Antifungal activity of a new triterpenoid glycoside from Pithecellobium racemosum (M.).
OBJECTIVE
In a continuation of our search for novel antifungal compounds from higher plants, the standard extract of the bark of Pithecellobium racemosum was found to have good activity against important AIDS-related opportunistic yeasts.


METHODS
The extract was subjected to bioguided fractionation using silica gel column chromatography which led to purification of triterpene glycosides. The structures of these compounds were determined by a combination of spectroscopic (IR, NMR, HRMS) and chemical methods.


RESULTS
Compound 1 is a new glycoside, 3-O[alpha-L-arabinopyranosyl (1-2)][alpha-L arabinopyranosyl (1-6)]2-acetoamido-2-deoxy-beta-D-glucopyranosyl oleanolic acid and Compound 2 was identified as the known compound 3-O-[alpha-L-arabinopyranosyl (1-2)]alpha-L-arabinopyranosyl (1-6)] 2-acetamido-2-deoxy-beta-D-glucopyranosyl echinocystic acid.


CONCLUSIONS
Compound 1 is a new glycoside, 3-O-[alpha-L-arabinopyranosyl (1-2)]alpha-L-arabinopyranosyl (1-6)]-2-acetoamido-2-deoxy-beta-D-glucopyranosyl oleanolic acid and exhibits moderate antifungal activity against T. mentogrophytes, C. albicans and S. cerevisiae with MIC values of 6.25, 12.5 and 12.5 micrograms/ml respectively.
Khan
I A
IA
National Center for Development of Natural Products, School of Pharmacy, University of Mississippi 38677, USA.
Clark
A M
AM
McChesney
J D
JD
D000935:Antifungal Agents / Q000302:isolation & purification* / Q000494:pharmacology; D001231:Aspergillus flavus / Q000187:drug effects; D001232:Aspergillus fumigatus / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D002850:Chromatography, Gel; D003455:Cryptococcus neoformans / Q000187:drug effects; D006027:Glycosides / Q000302:isolation & purification* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D012441:Saccharomyces cerevisiae / Q000187:drug effects; D012503:Saponins / Q000302:isolation & purification; D014249:Trichophyton / Q000187:drug effects
C106258:3-O-(arabinopyranosyl(1-2))-(arabinopyranosyl(1-6))-2-acetamido-2-deoxyglucopyranosyl oleanolic acid; D000935:Antifungal Agents; D006027:Glycosides; D012503:Saponins