ISOLATION OF HYPOTENSIVE FLAVONOIDS FROM CHENOPODIUM SPECIES GROWING IN EGYPT

TLC investigation of the flavonoid fraction of Chenopodium murale L. r evealed the presence of three components. The major was identified as kaempferol-3,7-dirhamnoside 1 (kaempferitrin; lespedin) through its MP , UV, IR, MS and NMR (H-H COSY and H-C. HECTOR) sprectra. Testing the effect of compound 1 as well as the total flavonoid mixture on the rab bit cardiovascular system, showed dose-related hypotension and bradyca rdia. Compound 1 also produced a dose-related hypotension in genetical ly prone hypertensive rats. Compound 1 did not block alpha(1) or beta( 1)-adrenoceptors when tested using isolated guinea-pig strip and atria , respectively. Quantification of 1 in C. ambrosoides, C. murale, C. f icifolium and C. album revealed that the former contains the highest l evel. (C) 1997 John Wiley & Sons, Ltd.