Studies On The Chemical Constituents Of Leonurus Japonicus Houtt.

Leonurus japonicus Houtt., also known as yimucao in Chinese, is one of the 23 species of Leonurus genus of Lamiaceae family. Various preparations of this plant are mainly used for the treatment of cardiovascular diseases, gynaecological problems and nephritis. Chemical constituents of this genus comprise diterpenes, iridoids, phenylpropanoids, alkaloids, flavonoids, etc. This paper describes the isolation and structure elucidation of the constituents from Leonurus japonicus Houtt..Air-dried aerial part of Leonurus japonicus Houtt. was extracted with water and precipitated with EtOH. By means of solvent extraction, chromatography on macroporous resin, silica gel and Sephadex LH-20 column, 20 compounds were isolated. NMR and MS were employed for structure identification, 16 of them were elucidated as: Heteronone A (1), Heteronone B (2), isolavandulifolioside (3), lavandulifolioside (4), Heterolignan (5), 5,7,3',4',5'-pentamethoxy-flavone (6), wogonin (7), apigenin-7-O-P-D-glucopyranoside (8), daidzein (9),quercetin (10), rutin (11), benzoic acid (12), salicylic acid (13) , syringic acid (14), adenosine (15), stigmasterol(16). Among them 2 and 5 were novel compounds, 3, 6, 7, 9, 15 were isolated from Leonurus genus for the first time.