Assamicains, oolonghomobisflavans, and theasinensins also had potent antilipase activity. Monodesgalloyl (36) or dides-
galloyl (38) oolonghomobisflavans showed less activity than oolonghomobisflavan A (35) and B (37). The activity levels of theasinensins also depended on the number of galloyl groups within their molecular structures, such as oolongtheanin 3′-O-gallate (45) and theasinensin D (42) and A (39) with IC50s of 0.068, 0.098, and 0.142 μM, respectively. Although catechin had no activity (IC50 > 20 μM), an inhibitory activity of dehydrodicatechin A (46), a dimeric compound of catechin, was markedly increased (IC50 ) 3.09 μM). The relationship between the chemical structure and activity suggested that the inhibitory effects advanced with the dimerization of flavan-3-ol.