Geranins C and D, Additional New Antiprotozoal A-Type Proanthocyanidins from Geranium niveum [1]

Abstract

Two new additional A-type proanthocyanidins have been isolated from Geranium niveum. Their structures were determined by spectroscopic, chemical and chiroptical methods as epi-afzelechin-(4β→8,2β→O→7)-gallocatechin (1) and epi-afzelechin-(4β→8,2β→O→7)-afzelechin-(4β→8,2β→O→7)-afzelechin (2). Proanthocyanidins 1 and 2 were given the trivial names of geranins C and D, respectively. Compound 2 showed moderate antiprotozoal activity against Entamoeba histolytica and Giardia lamblia, whereas 1 exhibited weak activity toward E. histolytica.

References

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1 Part XLV in the series Chemical Studies on Mexican Plants Used in Traditional Medicine. Taken in part from the Ph.D. thesis of F. Calzada.