LAUSR

Liriope Lour. are perennial herbaceous plants in the Liliaceae family, distributed mainly in southern China. The tubers of Liriope Lour. are used in Chinese folk medicine. Liriope is recorded in the Chinese Pharmacopoeia (1995 edition) including Liriope spicata (Thunb.) Lour. var. prolifera Y. T. Ma and Liriope musacarli (Decne.) Bailey [1–3]. As a tonic to moisten yin, it has been employed in traditional Chinese medicine for the treatment of asthma and bronchial and lung inflammation [4]. Due to more and more bioactive substances isolated from this family, such as steroidal saponins and polysaccharides, the plants of Liriope Lour. have become the subject of continuing and growing interest. In our search for plant-derived bioactive compounds [5–8], the plant of L. graminifolia was chemically studied. Eight compounds were isolated and identified as methylophiopogonanone B (1), 5,7-dihydroxy-6-methyl-3-(4-methoxybenzyl)-chroman-4-one (2), 7,4 -dihydroxy-5-methoxyflavanone (3), hesperidin (4), 25(S)-ruscogenin-1-O-D-xylopyranoside-3-O-Lrhamnopyranoside (5), 25(R)-ruscogenin-1-O-L-rhamnopyranosyl-(1 2)-D-xylopyranoside (6), (25S)-spirost-5-ene3 ,17 -diol-3-O-D-xylopyranosyl-(1 3)-L-arabinofuranosyl(1 2)-[ -L-rhamnopyranosyl(1 4)]-D-glucopyranoside (7), and 25(R,S)-ruscogenin-1-O-sulfate-3-O-L-rhamnopyranoside (8). Their structures were determined by UV, MS, and 1D and 2D NMR analysis. All of them were isolated from this plants for the first time. It provided the experimental data for the further development of L. graminifolia (L.) Baker. Plant Material. The stalks of L. graminifolia were purchased in August 2009 from Chongqing Institute of Medicinal Plant Cultivation, China and identified by Prof. Bin Wu (Zhejiang University, Hangzhou, P. R. China). A voucher specimen (No. Zjgsu 20090808) has been deposited at the School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, P. R. China. Sample Preparation. The air-dried stalks (15 kg) were extracted twice with 95% ethanol and 75% ethanol under reflux for 4 h. Then they were concentrated in vacuo to afford a crude extract (1.5 kg), which was then dissolved in H2O and partitioned with petroleum ether (PE), EtOAc, and n-BuOH successively. The solvents were evaporated to produce PE (131 g), EtOAc (150 g), and n-BuOH (429 g) fractions. The EtOAc fraction was separated by chromatography on silica gel (160–200 mesh) eluted with PE–EtOAc gradient (100:0 to 0:100), and then purified by Sephadex LH-20 and pre-HPLC to yield compounds 1 (48 mg), 2 (30 mg), and 3 (68 mg). The n-butanol fraction was isolated by D101 macroporous adsorption resin eluted with water and 25%, 50%, 75%, and 95% ethanol to obtain the components with different polarity. The 50% ethanol fraction was isolated by medium-pressure liquid chromatograph (MPLC) and Sephadex LH-20 to obtain compounds 4 (121 mg) and 8 (213 mg). The 75% ethanol fraction was isolated by pre-HPLC to obtain compounds 5 (56 mg), 6 (101 mg), and 7 (95 mg). Methylophiopogonanone B (1). Colorless needle crystals, mp 157–158 C. ESI-MS m/z 327 [M – H]–. 1H NMR (500 MHz, DMSO-d6, , ppm, J/Hz): 12.40 (1H, s, 5-OH), 9.64 (1H, s, 7-OH), 7.15 (2H, d, J = 8.5, H-2 , 6 ), 6.87 (2H, d, J = 8.5, H-3 , 5 ), 4.28 (1H, m, H-2b), 4.08 (1H, m, H-2a), 3.72 (3H, s, MeO-7 ), 3.06 (1H, m, H-9b), 2.98 (1H, m, H-3), 2.66 (1H, dd, J = 11.5, 8.0, H-9a), 1.95 (3H, s, Me-13), 1.93 (3H, s, Me-12). 13C NMR (125 MHz, DMSO-d6, , ppm): 68.9 (C-2), 45.5 (C-3), 198.3 (C-4), 158.6 (C-5), 102.2 (C-6), 162.3 (C-7), 103.3 (C-8), 31.1 (C-9), 157.9 (C-10), 101.1 (C-11), 8.0 (C-12), 7.6 (C-13), 130.0 (C-1 ), 130.0 (C-2 ), 113.8 (C-3 ), 157.3 (C-4 ), 113.8 (C-5 ), 130.0 (C-6 ), 55.0 (C-7 ) [9, 10].