Chemical Studies on Mexican Plants Used in Traditional Medicine, VI. Additional New 4-Phenylcoumarins from Exostema caribaeum

Abstract
Six additional 4-phenylcoumarins have been isolated from the MeOH extract of the bark of Exostema caribaeum. Their structures were determined by physcial and chemical methods as 4''-5''-dihydroxy-7-methoxy-4-phenyl-5,2''-oxidocounmarin [1], 5,7,4''-trimethoxy-4-phenylcoumarin [2], 5,3''-dihydroxy-7,4''-dimethoxy-4-phenylcoumarin [3], 5-O-.beta.-D-galactopyranosyl-7,4''-dimethoxy-4-phenylcoumarin [6], 5-O-.beta.-D-glucopyranosyl-3'', 4''-dihydroxy-7-methoxy-4-phenylcoumarin [7], and 5-O-(6"-acetyl)-.BETA.-D-galactopyranosyl-3'', 4''-dihydrozyl-7-methoxy-4-phenlcoumarin [9]. The last four compounds are new natural products.