Chemical constituents from Houttuynia cordata

Houttuynia cordata Thunb. (Saururaceae) is traditionally used as a medicinal plant for treatment of inflammation-related disorders [1] and protection against oxidative stress in Asian countries [2]. The aerial parts of H. cordata contain various types of flavonoids and some alkaloids [3]. Twenty compounds were isolated from H. cordata using chromatographic and semi-preparative HPLC techniques, and found to be two harmala alkaloids, one phenolic acid, four chlorogenic acid derivatives, three phenolic glycosides, two phenylpropanoids derivatives and eight flavonoids. Chemical structures of these compounds were characterized by spectroscopic methods as 3a,12a-dihydro-2H-furo[3,2-b]indolo[3,2,1-ij][1,5]naphthyridine-1,1(4H)-diol (1), perlolyrine (2), 4-hydroxycinnamic acid (3), neochlorogenic acid (4), neochlorogenic acid methyl ester (5), cryptocholorogenic acid (6), cryptochlorogenic acid methyl ester (7), benzyl-β-D-glucoside (8), β-phenylethoxy-β-D-glucopyranoside (9), dopaol-β-D-glucoside (10), guaiacylglycerol (11), (+)-(7S,8S)-guaiacylglycerol-8-O-β-D-glucopyranoside (12), luteolin (13), quercetin (14), apigenin (15), afzelin (16), quercitrin (17), hyperoside (18), kaempferol-3-O-α-L-rhamnosyl-7-O-β-D-glucoside (19) and quercetin-3-O-α-L-rhamnosyl-7-O-β-D-glucoside (20). Among them, compound 1 was isolated from nature for the first time. Compounds 2, 7, 9, 11, 12 and 19 are newly reported from H. cordata.