택사(Alismatis Rhizoma)와 목통(Akebiae Caulis)의 성분연구

Abstract

Phytochemical studies on the chemical constituents of Alismatis Rhizoma and Akebiae Caulis

Jin Hongguang Advisor : Prof. Woo Eun-Rhan, Ph.D. Department of Pharmacy, Graduate School of Chosun University

Alisma orientale (Sam.) Juz. belongs to the family Alismataceae, and the dried rhizomes of A. orientale have been used as traditional Oriental medicine to treat diuretics, hypolipidemic, and diabetes. Previous phytochemical and pharmacological investigations on this plant established the major chemical constituents as prostane-type triterpenes and various sesquiterpenes. As part of our ongoing search for biologically active compounds from nature, the dried rhizomes of A. orientale were phytochemically examined, As a result a new triterpenoid, named alisol Q 23-acetate(16), and fifteen known terpenes, alisol B 23-acetate (1), alisol B (2), alismol (3), β-sitosterol (4), 10-O-methyl-alismoxide (5), alismoxide (6), 4β,12-dihydroxyguaian-6,10-diene (7), 16β-hydroxyalisol B 23-acetate (8), alisol C 23-acetate (9), 11-deoxyalisol C (10), 13β,17β-epoxyalisol B 23-acetate (11), alisol A (12), alisolide (13), 16β-methoxyalisol B monoacetate (14), and alisol A 24-acetate (15), have been isolated from hexane and CH2Cl2 soluble parts by various chromatographic methods, including silica gel, RP-18, and MCI. The structures of compounds (1-16) were identified based on extensive spectroscopic analyses, including UV, IR, NMR, MS, and HRMS, as well as comparison with literature data. Akebia quinata Decaisene (Lardizabalaceae) is a creeping woody vine widely distributed in East Asia, including Korea, China, and Japan. Traditionally, its dried stem is used mainly as a diuretic agent for the treatment of edema and rheumatic pain. Previous studies on the lignum of A. quinata yielded some saponins and triterpenoid compounds, such as akebosides Stb~f, h~k, quinatosides A~D, and norajunolic acid. During our phytochemical investigation of the n-butanol soluble part of this plant, three new lignan glycosides, akequintoside A (30), akequintoside B (28), and akequintoside C (29), and a new megastigmane glycoside, akequintoside D (27), along with eleven known compounds, vanilloloside (17), 3,4-dihydroxyphenylethyl alcohol 8-O-β-D-glucopyranoside (18), cuneataside D (19), salidroside (20), 3,4,5-trimethoxyphenyl-β-D-glucopyranoside (21), 3,4-dimethoxyphenyl-6-O-(α-L-rhamnopyranosyl)-β-D-glucopyranoside (22), 3-O-caffeoylquinic acid (23), E-Syringin (24), (6S,9R)-3-oxo-α-ionol-9-O-β-D-glucopyranoside (25), methyl-3-O-caffeoylquinate (26), and calceolarioside B (31), were isolated by repeated silica gel, Sephadex LH-20, LiChroprep RP-18, and MCI gel column chromatography. The chemical structures of compounds 17-31 were identified on the basis of 1D and 2D NMR, including 1H-1H COSY, HSQC, HMBC, and NOE, as well as UV, IR, and MS spectroscopic analyses. These compounds were isolated from this plant for the first time.

Keywords: Alismatis Rhizoma; Akebiae Caulis; Triterpenoid; Megastigmane glycoside; Lignan glycosides; alisol Q 23-acetate; Akequintosides