Abstract: | Continuous exploration of the chemical constituents of Combretaceous plants has led to the discovery of two novel ellagitannins, quisqualin A ( 1 ) and quisqualin B ( 2 ), from the fruits of Quisqualis indica. A total of twenty-one other tannins were also isolated from either the fruits or leaves of Q. indica. including [I] eleven ellagitannins: 2,3-(S)-HHDP-D-glucose ( 3 ), 2,3-(S)-HHDP-4-O-galloyl-D-glucose ( 4 ), 2,3-(S)-HHDP-6-O-galloyl-D-glucose ( 5 ), 2,3-(S)-HHDPA6-di-O-galloyl-D-glucose ( 6 ). pedunculagin ( 7 ), punicalagin ( 8 ), eugeniin ( 9 ), 1-desgalloyleugeniin ( 10 ), casuariin ( 11 ), 5-desgalloylstachyurin ( 12 ), castalagin ( 13 ); [II] five gallotannins-. 6-O-galloyl-D-glucose ( 14 ), 1,6-di-O-galloyl-β-D-glucose ( 15 ), 2,3-di-O-galloyl-D-glucose ( 16 ), 3,4-di-O-galloyl-D-glucose ( 17 ), 4,6-di-O-galloyl-D-glucose ( 18 ); [III] four phenol-carboxylic acids: gallic acid ( 19 ), ellagic acid ( 20 ), flavogallonic acid ( 21 ), brevifolin carboxylic acid ( 22 ) and [IV] one other hydrolyzable tannin: punicalin ( 23 ). |