[Structural elucidation of the anticoagulation and anticancer constituents from Allium chinense]

Six compounds were isolated from the anticoagulation and anticancer fractions of the bulbs of Allium chinense G. Don. On the basis of chemical evidence and spectral analysis (IR, EI-MS, 1HNMR, 13CNMR, 1H-1H COSY, HMBC, HMQC and NOESY), their structures were established as (25R, S)-5 alpha-spirostane-3 beta-ol 3-O-(beta-D-glucopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->3)]-beta-D- glucopyranosyl-(1-->4)-beta-D-galactopyranoside) (1), (25R, S)-5 alpha-spirostane-3 beta-ol 3-O-(beta-D-glucopyranosyl (1-->2)-[beta-D-glucopyranosyl-(1-->3)](6-acetyl-beta-D-glucopyranosyl)- (1-->4)-beta-D-galactopyranoside) (2), (25R, S)-5 alpha-spirostane-2 alpha, 3 beta-diol 3-O-(beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-beta-D- galactopyranoside) (3), (25S)-24-O-beta-D-glucopyranosyl-3 beta, 24 beta-dihydroxy-5 alpha-spirost-3-O-alpha-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside (4), chinenoside II (5) and 2,3,4,9-tetrahydro-1-methyl-1H-pyrido [3,4-b] indole-3-carboxylic acid (6). 4 is a new steroidal saponin, named chinenoside VI. Compounds 1 to 3 are three pairs of steroidal saponin epimers. Among them, the 25S epimer of 2 is first reported, the 25R epimer of 2 and compound 6 were isolated from this title plant for the first time. The relative configuration of compound 6 was firstly determined by NOESY spectrum, and signals of C, H were assigned definitely.