010059, China b First Affiliated Hospital, Inner Mongolia Medical University, Hohhot , China Published online: 06 Jan 2015.

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1 This article was downloaded by: [University of Nebraska, Lincoln] On: 05 April 2015, At: 06:57 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: Registered office: Mortimer House, Mortimer Street, London W1T 3JH, UK Click for updates Journal of Asian Natural Products Research Publication details, including instructions for authors and subscription information: New steroidal glycosides from Hosta plantaginea (Lam.) Aschers Xiao-Juan Li ab, Li Wang a, Pei-Feng Xue a, Hong-Xia Xie ab, Hui Wei a & Jing Wang a a School of Pharmacy, Inner Mongolia Medical University, Hohhot , China b First Affiliated Hospital, Inner Mongolia Medical University, Hohhot , China Published online: 06 Jan To cite this article: Xiao-Juan Li, Li Wang, Pei-Feng Xue, Hong-Xia Xie, Hui Wei & Jing Wang (2015) New steroidal glycosides from Hosta plantaginea (Lam.) Aschers, Journal of Asian Natural Products Research, 17:3, , DOI: / To link to this article: PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the Content ) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &

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3 Journal of Asian Natural Products Research, 2015 Vol. 17, No. 3, , New steroidal glycosides from Hosta plantaginea (Lam.) Aschers Xiao-Juan Li ab1, Li Wang a1, Pei-Feng Xue a *, Hong-Xia Xie ab, Hui Wei a and Jing Wang a a School of Pharmacy, Inner Mongolia Medical University, Hohhot , China; b First Affiliated Hospital, Inner Mongolia Medical University, Hohhot , China (Received 19 February 2014; final version received 7 December 2014) Four new furostanol glycosides were isolated from the flowers of Hosta plantaginea (Lam.) Aschers. On the basis of spectroscopic methods including 1D and 2D NMR experiments, their structures were elucidated as 26-O-b-D-glucopyranosyl-(25R)-22- O-methyl-5a-furostan-2a,3b,22j,26-tetrol 3-O-a-L-rhamnopyranosyl-(1! 4)-O-b- D-xylopyranosyl-(1! 3)-[O-b-D-glucopyranosyl-(1! 2)]-O-b-D-glucopyranosyl- (1! 4)-b-D-galactopyranoside (hostaplantagineoside A, 1), 26-O-b-D-glucopyranosyl-(25R)-5a-furostan-20(22)-ene-2a,3b,26-triol-3-O-b-D-glucopyranosyl-(1! 2)- [O-b-D-xylopyranosyl-(1! 3)]-O-b-D-glucopyranosyl-(1! 4)-b-D-galactopyranoside (hostaplantagineoside B, 2), 26-O-b-D-glucopyranosyl-(25R)-5a-furostan-22(23)- ene-2a,3b,20a,26-tetraol-3-o-b-d-glucopyranosyl-(1! 2)-[O-b-D-xylopyranosyl- (1! 3)]-O-b-D-glucopyranosyl-(1! 4)-O-b-D-galactopyranoside (hostaplantagineoside C, 3), 26-O-b-D-glucopyranosyl-(25R)-5a-furostan-20(22)-ene-2a,3b,26-triol-3- O-a-L-rhamnopyranosyl-(1! 4)-O-b-D-xylopyranosyl-(1! 3)-[O-b-D-glucopyranosyl-(1! 2)]-O-b-D-glucopyranosyl-(1! 4)-b-D-galactopyranoside (hostaplantagineoside D, 4). Keywords: Hosta plantaginea; steroidal glycosides; furostanol saponins 1. Introduction Hosta plantaginea (Lam.) Aschers, belonging to the family Liliaceae, is cultivated all over China. The flower of H. plantaginea has been widely used in traditional Mongolian medicine for the treatment of sore throat, mute, lung heat, and toxic heat [1]. Previous phytochemical investigations of this plant have shown the presence of steroidal glycosides [2,3], flavonol glycosides [4], and alkaloids [5,6]. Some steroidal glycosides showed antibacterial and antitumoral activity. As a continuation of study on this Mongolian herb, we report on the isolation and structural elucidation of four new furostanol glycosides (hostaplantagineosides A, B, C, and D). 2. Results and discussion Compound 1 was obtained as a white amorphous powder with ½aŠ 20 D (c 0.09, MeOH). Positive reactions of 1 on Liebermann Burchard, Molish, and Ehrlich tests suggested that this compound was a furostanol glycoside. The molecular formula was determined to be C 63 H 106 O 33 by HR-ESI-MS at m/z [M þ Na] þ. The 1 H NMR spectrum showed signals for four typical steroid methyls at d 0.76 (s), 0.68 (s), 1.16 (d), and 0.98 (d), respectively. Six anomeric proton signals were also observed at d 4.84, 4.95, 5.17, 5.24, 5.45, and In 13 CNMR spectrum (Tables 1 and 2), the carbon signals assignable to the aglycone moiety and the glucosyl unit linked to C-26 were *Corresponding author. xpfdc@vip.sina.com q 2015 Taylor & Francis

4 Journal of Asian Natural Products Research 225 Table C NMR spectral data of the aglycone moieties of compounds 1 4 (pyridine-d 5 ). No No OCH identical to those of (25R)-22-O-methyl- 5a-furostane-2a,3b,22j,26-tetrol 26-O-b- D-glucopyranoside in the literature [7], except for the signals of C-2, C-3, and C-4, which were shifted upfield by 2.6 ppm, downfield by 7.6 ppm and upfield by 7.6 ppm, respectively. This indicated that compound 1 was 3-O-glycoside of the above analogue. The 25R configuration was also confirmed by the difference between the chemical shifts of the Table 2. two protons at C-26 (D ¼ d H-26a d H- 26b ¼ ¼ 0.43, 0.48) [8]. The 2a and 3b configurations of the oxygen atoms were also deduced from the multiplicities of the 2-H proton, 3 J H-2, H-1ax ¼ 11.2 Hz, 3 J H-2,H-1eq ¼ 5.2 Hz, and 3 J H-2,H-3 ¼ 9.2 Hz. The 3b configuration was further supported by the NOE correlations from H-3 to H-1a(ax) and H-5a(ax). Moreover, the carbon signals attributable to the remaining five sugar moieties of 1 were 13 C NMR spectral data of the sugar moieties of compounds 1 4 (pyridine-d 5 ). No No (3-O)-b-D-gal (Glc 3 )-b-d-xyl (Xyl 4 )-a-l-rha (Gal 4 )-b-d-glc (26-O)-b-D-Glc (Glc 2 )-b-d-glc

5 226 X.-J. Li et al. consistent with those of gitogenin 3-O-{Ob-D-glucopyranosyl-(1! 2)-O-[O-a-Lrhamnopyranosyl-(1! 4)-b-D-xylopyranosyl-(1! 3)]-O-b-D-glucopyranosyl- (1! 4)-b-D-galactopyranoside} [7], which suggested that 1 had the same sugar chain linked to C-3 as the above analogue. GC analysis of acid hydrolysis products of 1 indicated the presence of D-galactosyl, D- glucosyl, D-xylosyl as well as L-rhamnosyl units. The a configuration for rhamnose was determined by comparing the 13 C NMR spectral data with those in the literature [9]. The b-configurations for galactose, glucose, and xylose were determined by their anomeric coupling constants of more than 7.0 Hz. In the HMBC spectrum, the correlation between OCH 3 C-22 at d 3.24 and C-22 at d confirmed a methoxyl group attached at C-22 of the aglycone, the correlation between the anomeric proton at d 4.84 and C-26 at d 75.2 suggested one D-glucose attached to C-26 of the aglycone, and the correlation between the anomeric proton at d 4.95 and C-3 at d 84.3 suggested the D- galactose linked to C-3 of the aglycone. In addition, the correlations between H-1 00 at d 5.17 and C-4 0 at d 79.4, H at d 5.57 and C-2 00 at d 81.3, H at d 5.24 and C-3 00 at d 86.6, H at d 5.45 and C at d 76.1 revealed the oligosaccharide sequence Rha-(1! 4)-Xyl-(1! 3)-[Glc-(1! 2)]- Glc-(1! 4)-Gal. Thus, compound 1 was finally established as 26-O-b-D-glucopyr- anosyl-(25r)-22-o-methyl-5a-furostan- 2a,3b,22j,26-tetrol-3-O-a-L-rhamnopyranosyl-(1! 4)-O-b-D-xylopyranosyl- (1! 3)-[O-b-D-glucopyranosyl-(1! 2)]- O-b-D-glucopyranosyl-(1! 4)-b-D-galactopyranoside, named as hostaplantagineoside A (Figure 1). Compound 2 was obtained as a white amorphous powder with ½aŠ 20 D (c 0.06, MeOH). Positive reactions of 2 on Liebermann Burchard, Molish, and Ehrlich tests suggested that this compound was also a furostanol glycoside. The molecular formula was determined to be C 56 H 92 O 28 by HR-ESI-MS at m/z [M þ H] þ and [M þ Na] þ. The 1 H NMR spectrum showed signals for four steroid methyls at d 0.69 (s), 0.67 (s), 1.60 (s), and 1.00 (d), respectively. Five anomeric proton signals were also observed at d 4.90, 4.91, 5.19, 5.22, and The carbon signals assignable to the aglycone moiety of 2 were similar to those of compound 1, except for the appearance of two quaternary olefinic carbons at d and instead of two methine carbons at d and 40.5, which suggested the presence of a double bond. The chemical shifts of two olefinic carbons indicated that the double bond was located at C-20 (C-22) [10,11], which was confirmed by the correlations in HMBC spectrum between H-21 at d 1.60 and C-17 at d 64.5, C-20 at d 103.6, and C- 22 at d 152.3, respectively. The configurations of 25R, 2a and 3b were determined by the same methods as those of 1. Therefore, the aglycone of 2 was determined as (25R)-5a-furostan-20(22)-enolide-2a,3b,26-triol. In addition, carbon signals attributed to the sugar moieties of 2 also resembled to those of 1, except for the absence of a set of signals corresponding to the a-l-rhamnopyranosyl unit. Appropriately, the anomeric proton signal assignable to the rhamnosyl unit was absent in 1 H NMR spectrum of 2. Thus, compound 2 was finally determined as 26-O-b-D-glucopyranosyl-(25R)-5a-furostan-20(22)-ene-2a,3b,26-triol-3-O-b-Dglucopyranosyl-(1! 2)-[O-b-D-xylopyranosyl-(1! 3)]-O-b-D-glucopyranosyl- (1! 4)-b-D-galactopyranoside, named as hostaplantagineoside B (Figure 1). Compound 3 was obtained as a white amorphous powder with ½aŠ 20 D (c 0.13 MeOH). Positive reactions of 3 on Liebermann Burchard, Molish, and Ehrlich tests suggested that this compound was also a furostanol glycoside. The molecular formula was determined to be C 56 H 92 O 29 by HR-ESI-MS at m/z [M þ Na] þ. The 1 H NMR spectrum

6 Journal of Asian Natural Products Research 227 Figure 1. Structures and key HMBC correlations of compounds 1 4. showed signals for four steroid methyls at d 0.84 (s), 0.69 (s), 1.71 (s), and 1.06 (d), respectively. Five anomeric proton signals were also observed at d 4.81, 4.91, 5.20, 5.23, and A trisubstituted olefinic proton signal at d in the 1 H NMR spectrum, a quaternary olefinic carbon signal at d and a tertiary olefinic carbon signal at d 91.6 in 13 CNMR spectrum indicated the presence of a trisubstituted double bond. A tertiary oxycarbon signal at d 76.7 was also shown in

7 228 X.-J. Li et al. 13 C NMR spectrum. Further comparison of the 13 C NMR data for the aglycone moiety of 3 with those of smilaxchinoside A in the literature [12] suggested that a a-hydroxyl group was attached to C-20 and a double bond was located at C-22 (C-23) which was also confirmed by the correlations in HMBC spectrum between H-21 at d 1.71 and C-17 at d 67.9, C-20 at d 76.7, and C-22 at d 163.6, respectively, and the correlations between H-23 at d and C-20, C-22. The configurations of 25R, 2a, and 3b were defined by the same methods as those of 1. The a-configuration of C-20 hydroxyl group was confirmed by the correlation between H-21 at d 1.71 and H- 18 at d 0.84 in NOESY spectrum. Therefore, the aglycone of 3 was determined as (25R)-5a-furostan-22(23)-ene-2a,3b,20a, 26-tetraol. In addition, the carbon signals attributable to the sugar moieties of 3 were consistent with those of compound 2. Thus, compound 3 was finally determined as 26- O-b-D-glucopyranosyl-(25R)-5a-furo- stan-22(23)-ene-2a,3b,20a,26-tetraol-3- O-b-D-glucopyranosyl-(1! 2)-[O-b-Dxylopyranosyl-(1! 3)]-O-b-D-glucopyranosyl-(1! 4)-b-D-galactopyranoside, named as hostaplantagineoside C (Figure 1). Compound 4 was obtained as a white amorphous powder with ½aŠ 20 D (c 0.07, MeOH). Positive reactions of 4 on Liebermann Burchard, Molish, and Ehrlich tests suggested that this compound was also a furostanol glycoside. The molecular formula was established to be C 62 H 102 O 32 by HR-ESI-MS at m/z [M þ H] þ. The 1 H NMR spectrum showed signals for four steroid methyls at d 0.67 (s), 0.69 (s), 1.60 (s), and 1.01 (d), respectively. Six anomeric proton signals were also observed at d 4.83, 4.91, 5.17, 5.23, 5.46, and All the 13 C NMR signals of 4 were identical to those of compound 2, except for a set of additional signals corresponding to an a-l-rhamnopyranosyl unit at d 99.8, 72.5, 72.5, 73.9, 70.0, and An additional proton signal at d 5.46 assignable to the anomeric proton of the a- L-rhamnopyranosyl unit was observed in 1 H NMR spectrum of 4. The correlation between H at d 5.46 and C at d 76.1 in the HMBC spectrum suggested that the rhamnose was linked to C of xylose. Therefore, compound 4 was finally determined as 26-O-b-D-glucopyranosyl-(25R)- 5a-furostan-20(22)-ene-2a,3b,26-triol-3- O-a-L-rhamnopyranosyl-(1! 4)-O-b-Dxylopyranosyl-(1! 3)-[O-b-D-glucopyranosyl-(1! 2)]-O-b-D-glucopyranosyl- (1! 4)-b-D-galactopyranoside, named as hostaplantagineoside D (Figure 1). 3. Experimental 3.1 General experimental procedures Optical rotations were obtained on 341 MC Polarimeter (Perkin-Elmer Co., Jena, Germany). IR spectra were recorded on a FRIT-8400S infrared spectrophotometer (Shimadzu Co., Kyoto, Japan). The NMR spectral data were recorded on Bruker AVANCEIII (400 MHz for 1 H and 100 MHz for 13 C) in C 5 D 5 N with trimethylsilane as an internal standard (Bruker Co., Zurich, Switzerland). The HR-ESI-MS data were obtained on the APEX IV (7.0T) Fourier transform mass spectrophotometer (Bruker Co.). Chromatography was carried out on Diaion HP-20 ( mm; Mitsubishi Chemical Co., Tokyo, Japan), silica gel ( mesh; Qingdao Haiyang Chemical Factory, Qingdao, China), RP-18 (50 mm; Merck Group, Darmstadt, Germany), and Sephadex LH-20 ( mm, GE- Healthcare Bio-Sciences AB, Uppsala, Sweden). GC analysis was carried out on a gas chromatograph (Shimadzu GC-2010, Shimadzu Co.) with a H 2 flame ionization detector and a DB-5 quartz capillary column (30 m 0.25 mm 0.25 mm). 3.2 Plant material The flowers of H. plantaginea (Lam.) Aschers were collected in September 2009 at Fuxin city, Liaoning province, China. The

8 Journal of Asian Natural Products Research 229 plant was identified by Prof. Xiu-Sheng Pang, School of Pharmacy, Inner Mongolia Medical University. A voucher specimen (WLJ-2009-HP-1) has been deposited in the Herbarium of the School of Pharmacy, Inner Mongolia Medical University. 3.3 Extraction and isolation The air-dried flowers of H. plantaginea (9.0 kg) were extracted with hot 70% EtOH for three times (2 h each). The extract was successively partitioned with petroleum ether and n-buoh. The n-buoh-soluble fraction (900 g) was subjected to Diaion HP-20 column, and then successively eluted with H 2 O, 30% EtOH, 50% EtOH, 70% EtOH, and 95% EtOH, yielding five fractions. Fifty percent EtOH eluate (150.0 g) was subjected to silica gel column, eluted with CHCl 3 MeOH H 2 O (50:10:1! 60:40:10) to yield 17 fractions (Frs A 1 A 17 ). Fr. A 17 (2.5 g) was chromatographed on silica gel column and eluted with CHCl 3 MeOH H 2 O (30:10:1! 60:40:10) to yield compound 1 (50 mg). Seventy percent EtOH eluate (120.0 g) was subjected to silica gel column, eluted with CHCl 3 MeOH H 2 O (50:10:1! 60:40:10) to yield 12 fractions (Frs B 1 B 12 ). Fr. B 12 (5.5 g) was repeatedly chromatographed on RP-18 column, eluted with MeOH H 2 O (50%! 60%), to yield compounds 2 (15 mg) and 3 (23 mg). Fr. B 10 (6.2 g) was chromatographed on RP-18 column, eluted with MeOH H 2 O (50%! 60%), and purified by Sephadex LH-20 column, eluted with MeOH H 2 O (60%), to yield compound 4 (100 mg) O-b-D-Glucopyranosyl-(25R)- 22-O-methyl-5a-furostan-2a,3b,22j,26- tetrol-3-o-a-l-rhamnopyranosyl-(1! 4)- O-b-D-xylopyranosyl-(1! 3)-[O-b-Dglucopyranosyl-(1! 2)]-O-b-Dglucopyranosyl-(1! 4)-b-Dgalactopyranoside (1) White amorphous powder; ½aŠ 20 D (c 0.09, MeOH). IR (KBr) n max : 3401, 2931,1641, 1452, 1421, 1381, 1161, 1072, 1047, 892 cm H NMR spectral data (400 MHz, pyridine-d 5 ): d 0.68 (3H, s, H- 19), 0.76 (3H, s, H-18), 0.98 (3H, d, J ¼ 6.4 Hz, H-27), 1.12 (1H, dd, J ¼ 12.8, 11.2 Hz, H-1ax), 1.16 (3H, d, J ¼ 6.8 Hz, H-21), 1.64 (3H, d, J ¼ 6.0 Hz, H ), 2.18 (1H, dd, J ¼ 12.8, 5.2 Hz, H-1eq), 3.24 (3H, s, 22-OCH 3 ), 3.58 (1H, dd, J ¼ 8.4, 6.8 Hz, H-26b), 3.78 (1H, ddd, J ¼ 11.2, 9.2, 5.2 Hz, H-2), (1H, m, H-3), (1H, m, H-26a), (1H, m, H-16), 4.84 (1H, d, J ¼ 7.2 Hz, 26-O-glc-H-1), 4.95 (1H, d, J ¼ 7.6 Hz, H-1 0 ), 5.17 (1H, d, J ¼ 7.2 Hz, H-1 00 ), 5.24 (1H, d, J ¼ 7.6 Hz, H ), 5.45 (1H, br s, H ), 5.57 (1H, d, J ¼ 7.6 Hz, H ). 13 C NMR spectral data (100 MHz, pyridine-d 5 ), see Tables 1 and 2. HR-ESI- MS: m/z [M þ Na] þ (calcd for C 63 H 106 O 33 Na, ) O-b-D-Glucopyranosyl-(25R)- 5a-furostan-20(22)-ene-2a,3b,26-triol-3- O-b-D-glucopyranosyl-(1! 2)-[b-Dxylopyranosyl-(1! 3)]-O-b-Dglucopyranosyl-(1! 4)-b-Dgalactopyranoside (2) White amorphous powder; ½aŠ 20 D (c 0.06, MeOH). IR (KBr) n max : 3413, 2930, 1648, 1457, 1417, 1382, 1161, 1077, 1037, 893 cm H NMR spectral data (400 MHz, pyridine-d 5 ): d 0.67 (3H, s, H- 19), 0.69 (3H, s, H-18), 1.00 (3H, d, J ¼ 6.4 Hz, H-27), 1.14 (1H, dd, J ¼ 12.8 Hz, 12.0 Hz, H-1ax), 1.60 (3H, s, H-21), 2.15 (1H, dd, J ¼ 12.8, 5.6 Hz, H-1eq), (1H, m, H-26b), 3.78 (1H, ddd, J ¼ 12.0, 8.8, 5.6 Hz, H-2), (1H, m, H-3), (1H, m, H-26a), 4.75 (1H, H-16), 4.90 (1H, d, J ¼ 7.6 Hz, H-1 0 ), 4.91 (1H, d, J ¼ 7.6 Hz, 26-O-glc-H-1), 5.19 (1H, d, J ¼ 8.0 Hz, H ), 5.22 (1H, d, J ¼ 8.0 Hz, H ), 5.56 (1H, d, J ¼ 7.6 Hz, H ). 13 C NMR spectral data (100 MHz, pyridine-d 5 ), see Tables 1 and 2. HR-ESI-MS: m/z [M þ H] þ (calcd for

9 230 X.-J. Li et al. C 56 H 93 O 28, ); [M þ Na] þ (calcd for C 56 H 92 O 28 Na, ) O-b-D-Glucopyranosyl-(25R)- 5a-furostan-22(23)-ene-2a,3b,20a,26- tetraol-3-o-b-d-glucopyranosyl-(1! 2)- [b-d-xylopyranosyl-(1! 3)]-O-b-Dglucopyranosyl-(1! 4)-b-Dgalactopyranoside (3) White amorphous powder; ½aŠ 20 D 25.2 (c 0.13 MeOH). IR (KBr) n max : 3405, 2930, 1653, 1456, 1419, 1374, 1160, 1074, 1039, 893 cm H NMR spectral data (400 MHz, pyridine-d 5 ): d 0.69 (3H, s, H- 19), 0.84 (3H, s, H-18), 1.06 (3H, d, J ¼ 6.4 Hz, H-27), 1.12 (1H, dd, J ¼ 12.4, 11.2 Hz, H-1ax), 1.71 (3H, s, H-21), 2.16 (1H, dd, J ¼ 12.4, 4.8 Hz, H-1eq), (1H, m, H-26b), 3.80(1H, ddd, J ¼ 11.2, 9.2, 4.8 Hz, H-2), (1H, m, H-3), (1H, m, H-26a), (1H, m, H-23), 4.81 (1H, d, J ¼ 7.6 Hz, H-1 0 ), 5.18 (1H, dd, J ¼ 11.2, 8.0 Hz, H-16), 4.91 (1H, d, J ¼ 7.6 Hz, 26- O-glc-H-1), 5.20 (1H, d, J ¼ 8.0 Hz, H ), 5.23 (1H, d, J ¼ 8.0 Hz, H ), 5.57 (1H, d, J ¼ 7.6 Hz, H ). 13 C NMR spectral data (100 MHz, pyridine-d 5 ), see Tables 1 and 2. HR-ESI-MS: m/z [M þ Na] þ (calcd for C 56 H 92 O 29 Na, ) O-b-D-Glucopyranosyl-(25R)- 5a-furostan-20(22)-ene-2a,3b,26-triol-3- O-a-L-rhamnopyranosyl-(1! 4)-O-b-Dxylopyranosyl-(1! 3)-[O-b-Dglucopyranosyl-(1! 2)]-O-b-Dglucopyranosyl-(1! 4)-b-Dgalactopyranoside (4) White amorphous powder; ½aŠ 20 D (c 0.07, MeOH). IR (KBr) n max : 3408, 2929, 1643, 1383, 1076, 1042, 891 cm H NMR spectral data (400 MHz, pyridined 5 ): d 0.67 (3H, s, H-18), 0.69 (3H, s, H-19), 1.01 (3H, d, J ¼ 6.8 Hz, H-27), 1.15 (1H, dd, J ¼ 12.4, 11.6 Hz, H-1ax), 1.60 (3H, s, H-21), 1.64 (3H, d, J ¼ 6.0 Hz, H ), 2.18 (1H, dd, J ¼ 12.4, 5.2 Hz, H-1eq), 3.60 (1H, dd, J ¼ 9.6, 5.6 Hz, H-26b), 3.78 (1H, ddd, J ¼ 11.6, 8.8, 5.2 Hz, H-2), (1H, m, H-3), (1H, m, H-26a), (1H, m, H-16), 4.83 (1H, d, J ¼ 7.6 Hz, 26-O-glc-H-1), 4.91 (1H, d, J ¼ 8.0 Hz, H-1 0 ), 5.17 (1H, d, J ¼ 7.6 Hz, H-1 00 ), 5.23 (1H, d, J ¼ 8.0 Hz, H ), 5.46 (1H, br s, H ), 5.57 (1H, d, J ¼ 7.6 Hz, H ). 13 C NMR spectral data (100 MHz, pyridine-d 5 ), see Tables 1 and 2. HR-ESI-MS: m/z [M þ H] þ (calcd for C 62 H 103 O 32, ). 3.4 Acid hydrolysis of compounds 1 4 Each solution of compounds 1 4 (3 mg) in 2 M HCl MeOH (4:1, 5 ml) was refluxed at 908C for 4 h. After removing MeOH, the residue was partitioned between H 2 O and CHCl 3. The supernatant layer was condensed to dryness and dissolved in pyridine (1 ml). L-Cysteine methyl ester hydrochloride (2 mg) was added to the solution and treated at 608C for 2h, followed by acetic anhydride (1 ml) at 908C for 2 h. The reaction mixture was condensed to dryness and dissolved in MeOH (0.5 ml), which was analyzed by GC [Shimadzu GC-2010 with a H 2 flame ionization detector; DB-5 quartz capillary column (30 m 0.25 mm 0.25 mm); column temperature, 100/2808C, programmed increase, 108C/min; carrier gas, N 2 (1.5 ml/min); injector and detector temperature, 2808C; injection volume, 0.5 ml; split ratio, 10:1]. The derivatives of L-rhamnose, D-xylose, D-glucose, and D-galactose were observed at 22.53, 24.26, 25.79, and min by the comparison of their retention times with those of standard samples (22.48, 24.20, 25.72, and min), respectively. Funding This work was financially supported by the National Natural Science Foundation of China [ ], the Natural Science Foundation of

10 Journal of Asian Natural Products Research 231 Inner Mongolia [2009BS1203], and the Science and Technology Projects of Inner Mongolia [ ]. Disclosure statement No potential conflict of interest was reported by the authors. Note 1. Co-first author: both authors contributed to this work equally. References [1] B.S. Luo, Identification of Drug (Mongolian Version) (Inner Mongolia People s Press, Hohhot, 1998). [2] J.Q. Liu, C.F. Wang, M.H. Qiu, and W.X. Hu, Chin. Tradit. Herb. Drugs 41, 520 (2010). [3] J.H. Zhang, H.X. Xie, P.F. Xue, and H.G. Zhang, Chin. Pharm. J. 45, 335 (2010). [4] H.X. Xie, J.H. Zhang, H.G. Zhang, and P.F. Xue, Chin. Pharm. J. 10, 733 (2009). [5] Y.H. Wang, S. Gao, F.M. Yang, Q.Y. Sun, J.S. Wang, H.Y. Liu, C.S. Li, Y.T. Di, S.L. Li, H.P. He, and X.J. Hao, Org. Lett. 9, 5279 (2007). [6] Y.H. Wang, Z.K. Zhang, F.M. Yang, Q.Y. Sun, H.P. He, Y.T. Di, S.Z. Mu, Y. Lu, Y. Chang, Q.T. Zhen, M. Ding, J.H. Dong, and X.J. Hao, J. Nat. Prod. 70, 1458 (2007). [7] Y. Mimaki, A. Kameyama, M. Kuroda, Y. Sashida, T. Hirano, K. Oka, K. Koike, and T. Nikado, Phytochemistry 44, 305 (1997). [8] P.K. Agrawal, Magn. Reson. Chem. 42, 990 (2004). [9] O. Tanaka, Yakugaku Zassi 105, 323 (1985). [10] J.P. Peng, X. Yao, T. Okuyama, and Y. Okada, Acta Pharm. Sin. 29, 526 (1994). [11] J.B. Zhang, B. Yu, and Y.Z. Hui, Chin. J. Org. Chem. 20, 663 (2000). [12] B. Shao, H.Z. Guo, Y.J. Cui, M. Ye, J. Han, and D.A. Guo, Phytochemistry 68, 623 (2007).

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