姚彩虹 ,許旭東,龔小妹,周小雷*,羅祖良*
1.廣西壯族自治區(qū)藥用植物園,廣西 南寧 530023
2.中國醫(yī)學科學院 北京協(xié)和醫(yī)學院 藥用植物研究所,北京 100193
3.新疆大學生命科學與技術學院,新疆 烏魯木齊 830046
彭縣雪膽Hemsleya pengxianensisW.J.Chang為葫蘆科(Cucurbitaceae)雪膽屬HemsleyaCogn.ex F.B.Forbes & Hemsl.植物,主要分布于云南、貴州、四川、重慶等地[1]。現(xiàn)代研究表明,彭縣雪膽主要含有葫蘆烷三萜類、木脂素類、有機酸類等成分[2]。目前,以化學成分雪膽素為主的雪膽素膠囊以及“苗藥”雪膽腸胃丸已在市場有售,主要用于治療菌痢、腸炎、支氣管炎、急性扁桃體炎[3],有著良好的開發(fā)前景。為進一步完善其藥效物質基礎,發(fā)現(xiàn)具有活性的化學成分,對瑤藥彭縣雪膽醋酸乙酯萃取部位進行了系統(tǒng)的分離,結合多種色譜分離方法,共分離得到17個葫蘆烷三萜類化合物,分別鑒定為彭縣雪膽萜A(hemsleyacin A,1)、jinfushanencin B(2)、短柄雪膽苷D(delavanoside D,3)、scandenogenin D(4)、jinfushanencin C(5)、jinfushanoside D(6)、hexanorcucurbitacin F(7)、短柄雪膽A(delavanoside A,8)、cucurbitacin V(9)、hemslepenside A(10)、jinfushanencin F(11)、scandenoside R3(12)、scandenoside R2(13)、巨花雪膽G(hemslecin G,14)、jinfushanoside A(15)、cucurbitacine F(16)、16-O-acetyl-cucurbitacin F(17),其中化合物1為新化合物,化合物2~9為首次從該屬植物中分離得到。采用MTT法對以上所分離得到化合物進行了體外抗腫瘤細胞活性篩選。結果表明,化合物1、5、10、14、16~17對HeLa細胞具有良好的抑制作用,半數(shù)抑制濃度(median inhibitory concentration,IC50)為2.82~7.13 μmol/L。
BrukerAvanceⅢ600型核磁共振波譜儀(德國Bruker公司);HW-40C凝膠(Toyopearl公司);賽默飛世爾LTQ-Obitrap XL液質聯(lián)用儀、LTQ-Obitrap XL型質譜儀(美國Thermo Fisher公司);制備型Aglient高效液相色譜儀(美國Aglient公司);MCI(日本三菱化學公司);柱色譜硅膠、薄層色譜用硅膠GF254(青島海洋化工有限公司);RE-2000B型旋轉蒸發(fā)儀(上海亞榮生化儀器廠);常規(guī)試劑均為分析純,娃哈哈水。
藥材于2017年采自于廣西南寧,經(jīng)云南省農(nóng)業(yè)科學院高山經(jīng)濟植物研究所易思蓉教授鑒定為葫蘆科雪膽屬植物彭縣雪膽H.pengxianensisW.J.Chang的干燥塊根,標本(CS170925)保存于廣西藥用植物園實驗室。
雪膽塊根10.0 kg粉碎后,以95%乙醇回流提取3次,每次3 h,回收乙醇得浸膏約1.1 kg。以3 L水溶解此浸膏后,依次用石油醚、醋酸乙酯、正丁醇萃取3次,每次1 L,減壓回收溶劑,得醋酸乙酯萃取物(350 g)。醋酸乙酯部位浸膏(350 g)經(jīng)硅膠柱色譜以二氯甲烷-甲醇(100∶0~0∶100)進行梯度洗脫,經(jīng)薄層色譜示蹤合并相同組分,共得到6個部分Fr.1~6。Fr.1經(jīng) MCI柱色譜分離,30%~100%甲醇梯度洗脫,得到7個組分(Fr.1.1~1.7)。Fr.1.2經(jīng)制備型HPLC(乙腈-水28∶72)制備得到化合物1(2.2 mg,tR=13.1 min)、2(1.8 mg,tR=15.1 min)。Fr.1.4經(jīng)Sephadex LH-20柱色譜(甲醇-二氯甲烷1∶1)及半制備高效液相色譜(乙腈-水35∶65)制備得到化合物3(3.0 mg,tR=15.1 min)、4(2.3 mg,tR=17.8 min)、5(2.6 mg,tR=25.3 min)。Fr.2經(jīng)Sephadex LH-20柱色譜(甲醇)及半制備高效液相色譜(乙腈-水25∶75)制備得到化合物6(2.1 mg,tR=15.6 min)、7(3.1 mg,tR=18.9 min)、8(3.1 mg,tR=24.6 min)。Fr.3經(jīng)過反相RP-18柱色譜分離,30%~100%甲醇水梯度洗脫,得到6個組分(Fr.3.1~3.6)。Fr.3.3經(jīng)制備型 HPLC(乙腈-水38∶62)制備得到化合物9(2.6 mg,tR=15.1 min)、10(1.8 mg,tR=19.1 min)、11(2.6 mg,tR=24.5 min)。Fr.4經(jīng)硅膠柱(200~300目)色譜,二氯甲烷-甲醇(40∶1~0∶1)梯度洗脫得到6個流分Fr.4.1~4.6。Fr.4.2經(jīng)制備型HPLC(乙腈-水37∶63)制備得到化合物12(2.6 mg,tR=13.6 min)、13(1.9 mg,tR=8.1 min)、14(2.1 mg,tR=25.5 min)。Fr.4.3經(jīng)過反相RP-18柱色譜分離,40%~100%甲醇梯度洗脫,得到6個組分(Fr.4.3.1~4.3.6)。Fr.4.3.4經(jīng)制備型HPLC(乙腈-水38∶62)制備得到化合物15(3.2 mg,tR=17.3 min)、16(1.9 mg,tR=20.5 min)、17(2.6 mg,tR=24.7 min)。
化合物1:白色粉末,易溶于甲醇,[α]20D+19.1°(c0.1,MeOH)。HR-ESI-MS顯示準分子離子峰m/z:641.332 0 [M+Na]+(計算值C34H50O10Na, 641.330 2),結合1H-NMR和13C-APT推斷該化合物的分子式為C34H50O10,不飽和度為11。UV圖譜顯示化合物在222 nm處有較強吸收,說明結構中存在共軛體系。IR圖譜顯示結構中存在羥基(3404、3422、3437 cm-1),甲基(2942、2839 cm-1),羰基(1710 cm-1)。
化合物1的1H-NMR(表1)在高場區(qū)顯示7個甲基信號δH1.18 (s), 1.24 (s), 1.37 (s), 1.40 (s),1.51(s), 2.13(s), 1.91 (s);1個烯烴的質子信號δH6.46(brs)。13C-APT(表1)譜給出36個碳信號,包括7個甲基信號δC20.3, 21.5, 19.6, 23.4, 25.2, 21.6,22.6,5個亞甲基信號δC35.6, 49.4, 44.3, 33.1, 35.6,7個次甲基信號70.3, 80.6, 124.6, 58.4, 36.7, 74.8,56.0,7個季碳信號δC44.7, 168.3, 48.1, 49.3, 50.4,80.1, 81.6,3個羰基信號δC216.2, 211.0, 199.7,2個酯基信號δC170.9, 170.6?;衔?的核磁數(shù)據(jù)與已知化合物巨花雪膽G[4]基本相似,不同之處在于化合物1額外存在1個羰基和乙?;盘?。進一步分析13C-APT數(shù)據(jù)發(fā)現(xiàn),在羰基的影響下,化合物1的C-5 (δC168.3), C-6 (δC124.6), C-7 (δC199.7) 較巨花雪膽G的C-5 (δC145.7), C-6 (δC122.9), C-7 (δC66.4) 向低場位移;C-16乙酰氧基取代后,化合物1的C-16 (δC74.8) 較巨花雪膽G的C-16 (δC71.3)向低場位移。HMBC(圖1)譜圖中,H-6 (δH6.47)與C-7 (δC199.7) 相關,H-16 (δH6.07) 與C-16位羰基 (δC170.9) 相關,提示羰基和乙?;謩e存在于C-7和C-16位。1H-NMR譜中C-3氫信號表現(xiàn)為δH3.53 (1H, d,J= 2.4 Hz),提示A環(huán)中存在2,3位置的順式二醇的結構。NOESY譜顯示,H-3和CH3-24,H-16和CH3-27存在相關,提示2-OH,3-OH及16-OAc均處于α位。因此,化合物1的結構被鑒定為2α,3α,20-三羥基葫蘆素-16,25-二乙酰氧基-5-烯-7,11,22-三酮,命名為彭縣雪膽萜A。
圖1 化合物1的1H-1H COSY、HMBC和NOESY相關Fig.1 Key 1H-1H COSY, HMBC and NOESY correlations of compound 1
表1 化合物1的NMR數(shù)據(jù) (600 MHz for 1H-NMR, 150 MHz for 13C-APT, in pyridine-d5)Table 1 NMR data (600 MHz for 1H-NMR, 150 MHz for 13C-APT, in pyridine-d5) of compound 1
化合物2:白色粉末,易溶于甲醇。ESI-MSm/z:495.216 7 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 0.69 (3H, s, H-18), 1.25 (3H, s, H-19), 0.86 (3H, d,J= 6.6 Hz, H-21), 1.15 (3H, s, H-28), 1.43 (3H, s,H-29), 1.01 (3H, s, H-30), 3.71 (1H, s, H-3), 5.70 (1H,d,J= 4.8 Hz, H-6), 5.91 (1H, t,J= 7.2 Hz, H-24),4.72 (2H, s, H-26), 4.73 (2H, s, H-27);13C-NMR (150 MHz, pyridine-d5)δ: 21.7 (C-1), 30.2 (C-2), 76.0(C-3), 42.3 (C-4), 141.9 (C-5), 119.4 (C-6), 24.6(C-7), 44.4 (C-8), 49.2 (C-9), 36.3 (C-10), 214.3(C-11), 49.5 (C-12), 49.5 (C-13), 50.0 (C-14), 34.9(C-15), 28.4 (C-16), 50.0 (C-17), 17.3 (C-18), 20.6(C-19), 36.4 (C-20), 18.3 (C-21), 36.4 (C-22), 24.9(C-23), 141.3 (C-24), 127.8 (C-25), 65.8 (C-26), 58.9(C-27), 18.5 (C-28), 26.7 (C-29), 28.3 (C-30)。以上數(shù)據(jù)與文獻報道一致[5],故鑒定化合物 2為jinfushanencin B。
化合物3:白色粉末,易溶于甲醇。ESI-MSm/z:641.497 0 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 0.68 (3H, s, H-18), 1.12 (3H, s, H-19), 0.83 (3H, d,J= 6.6 Hz, H-21), 1.83 (2H, s, H-27), 0.95 (3H, s,H-28), 1.10 (3H, s, H-29), 1.55 (3H, s, H-30), 3.62(1H, s, H-3) , 5.50 (1H, d,J= 6.0 Hz, H-6), 5.72 (1H,t,J= 6.6 Hz, H-24), 4.31 (2H, s, H-26), 4.89 (1H, d,J= 7.8 Hz, H-1′);13C-NMR (150 MHz, pyridine-d5)δ:22.3 (C-1), 28.9 (C-2), 87.6 (C-3), 42.4 (C-4), 141.7(C-5), 118.9 (C-6), 24.5 (C-7), 44.3 (C-8), 49.1 (C-9),36.3 (C-10), 214.1 (C-11), 49.4 (C-12), 49.5 (C-13),50.0 (C-14), 34.9 (C-15), 28.4 (C-16), 50.0 (C-17),17.3 (C-18), 20.7 (C-19), 36.2 (C-20), 18.6 (C-21),37.2 (C-22), 25.0 (C-23), 125.5 (C-24), 136.8 (C-25),68.5 (C-26), 14.4 (C-27), 19.2 (C-28), 28.7 (C-29),26.2 (C-30); 3-Glc: 107.8 (C-1′), 75.9 (C-2′), 79.1(C-3′), 72.2 (C-4′), 78.6 (C-5′), 63.4(C-6′),以上數(shù)據(jù)與文獻報道一致[6],故鑒定化合物3為短柄雪膽苷D。
化合物4:白色粉末,易溶于甲醇。ESI-MSm/z:541.321 8 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.28 (3H, s, H-18), 1.22 (3H, s, H-19), 1.46 (3H, s,H-21), 1.36 (3H, s, H-28), 1.29 (3H, s, H-29), 1.43(3H, s, H-30), 4.11 (1H, m, H-2), 3.42 (1H, d,J= 9.0 Hz, H-3), 5.69 (1H, d,J= 5.4 Hz, H-6), 5.11 (1H, m,H-16), 5.15 (1H, m, H-23), 6.71 (1H, d,J= 8.4 Hz,H-24), 4.73 (2H, s, H-26), 4.72 (2H, s, H-27);13C-NMR (150 MHz, pyridine-d5)δ: 34.4 (C-1), 70.7(C-2), 81.2 (C-3), 42.6 (C-4), 142.2 (C-5), 118.5(C-6), 24.0 (C-7), 42.6 (C-8), 49.0 (C-9), 34.0 (C-10),212.9 (C-11), 48.6 (C-12), 48.5 (C-13), 48.5 (C-14),41.5 (C-15), 70.3 (C-16), 55.8 (C-17), 19.9 (C-18),20.3 (C-19), 72.2 (C-20), 30.0 (C-21), 46.4 (C-22),70.6 (C-23), 128.3 (C-24), 142.1 (C-25), 65.3 (C-26),58.2 (C-27), 21.6 (C-28), 22.1 (C-29), 25.2 (C-30)。以上數(shù)據(jù)與文獻報道一致[7],故鑒定化合物4為scandenogenin D。
化合物5:白色粉末,易溶于甲醇。ESI-MSm/z:615.420 7 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.28 (3H, s, H-18), 1.30 (3H, s, H-29), 1.42 (3H, s,H-28), 1.51 (3H, s, H-26), 1.45 (3H, s, H-27), 1.54(3H, s, H-19), 1.51 (3H, s, H-30), 1.60 (3H, s, H-21),3.38 (3H, s, CH3-7), 3.49 (1H, d,J= 9.0 Hz, H-3),4.15 (1H, m, H-2), 3.67 (1H, d,J= 6.0 Hz, H-7), 4.94(1H, m, H-16), 6.10 (1H, d,J= 5.4 Hz, H-6);13C-NMR (150 MHz, pyridine-d5)δ: 34.8 (C-1), 71.2(C-2), 81.4 (C-3), 43.7 (C-4), 147.4 (C-5), 119.4(C-6), 76.7 (C-7), 48.7 (C-8), 48.9 (C-9), 35.6 (C-10),213.4 (C-11), 49.6 (C-12), 48.1(C-13), 50.8 (C-14),46.9 (C-15), 70.7 (C-16), 59.5 (C-17), 20.7(C-18),21.9 (C-19), 80.4 (C-20), 25.8 (C-21), 215.2 (C-22),32.6 (C-23), 35.7 (C-24), 82.2 (C-25), 26.3 (C-26),26.5 (C-27), 19.7 (C-28), 23.3 (C-29), 26.0 (C-30)170.6 (-OOCCH3), 22.4 (-OOCCH3)。以上數(shù)據(jù)與文獻報道一致[8],故鑒定化合物5為jinfushanencin C。
化合物6:白色粉末,易溶于甲醇。ESI-MSm/z:497.370 1 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 0.89 (3H, s, H-18), 1.46 (3H, s, H-29), 0.95 (3H, s,H-28), 4.71 (2H, s, H-26), 4.72 (2H, s, H-27), 1.37(3H, s, H-19), 1.22 (3H, s, H-30), 0.94 (3H, d,J= 6.0 Hz, H-21), 3.76 (1H, s, H-3) , 4.20 (1H, m, H-11),5.69 (1H, d,J= 5.4 Hz, H-6), 5.90 (1H, t,J= 6.0 Hz,H-24);13C-NMR (150 MHz, pyridine-d5)δ: 26.2(C-1), 31.3 (C-2), 76.7 (C-3), 42.8 (C-4), 144.8 (C-5),119.6 (C-6), 25.2 (C-7), 44.0 (C-8), 40.6 (C-9), 36.5(C-10), 78.3 (C-11), 41.3 (C-12), 47.8 (C-13), 50.3(C-14), 34.9 (C-15), 28.7 (C-16), 51.2 (C-17), 17.8(C-18), 26.8 (C-19), 37.5 (C-20), 19.9 (C-21), 37.4(C-22), 25.2 (C-23), 128.2 (C-24), 141.5 (C-25), 65.4(C-26), 58.9 (C-27), 19.0 (C-28), 27.3 (C-29), 27.5(C-30)。以上數(shù)據(jù)與文獻報道一致[8],故鑒定化合物6為jinfushanoside D。
化合物7:白色粉末,易溶于甲醇。ESI-MSm/z:427.333 3 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.22 (3H, s, H-18), 1.31 (3H, s, H-29), 0.79 (3H, s,H-28), 1.47 (3H, s, H-19), 1.54 (3H, s, H-30), 2.14(3H, s, H-21), 3.49 (1H, d,J= 6.6 Hz, H-3), 4.09 (1H,m, H-2), 3.43 (1H, d,J= 9.0 Hz, H-16), 5.72 (1H, d,J= 6.0 Hz, H-6);13C-NMR (150 MHz, pyridine-d5)δ:35.1 (C-1), 71.3 (C-2), 81.9 (C-3), 43.3 (C-4), 142.9(C-5), 118.9 (C-6), 24.6 (C-7), 43.8 (C-8), 49.5 (C-9),34.8 (C-10), 212.4 (C-11), 47.8 (C-12), 50.9 (C-13),49.6 (C-14), 46.5 (C-15), 71.7 (C-16), 68.4 (C-17), 19.6(C-18), 20.4 (C-19), 209.0 (C-20), 32.1 (C-21), 20.7(C-28), 22.8 (C-29), 25.9 (C-30)。以上數(shù)據(jù)與文獻報道一致[7],故鑒定化合物7為hexanorcucurbitacin F。
化合物8:白色粉末,易溶于甲醇。ESI-MSm/z:803.458 0 [M+Na]+。1H-NMR (600 MHz,pyridine-d5)δ: 0.71 (3H, s, H-18), 1.24 (3H, s, H-19),0.83 (3H, d,J= 6.6 Hz, H-21), 1.01 (3H, s, H-28),1.14 (3H, s, H-29), 1.42 (3H, s, H-30), 3.71 (1H, brs,H-3), 5.67 (1H, d,J= 6.0 Hz, H-6), 5.40 (1H, t,J=7.2 Hz, H-24), 4.56 (2H, s, H-27); 4.93 (1H, d,J= 7.8 Hz, H-1′), 5.36 (1H, d,J= 7.8 Hz, H-1′′);13C-NMR(150 MHz, pyridine-d5)δ: 21.7 (C-1), 30.2 (C-2), 76.0(C-3), 42.3 (C-4), 141.8 (C-5), 119.4 (C-6), 24.6(C-7), 44.4 (C-8), 49.5 (C-9), 37.2 (C-10), 214.4(C-11), 49.2 (C-12), 49.5 (C-13), 50.0 (C-14), 35.0(C-15), 28.5 (C-16), 50.0 (C-17), 17.4 (C-18), 20.6(C-19), 36.4 (C-20), 18.9 (C-21), 37.2 (C-22), 25.3(C-23), 130.4 (C-24), 132.6 (C-25), 22.3 (C-26), 67.7(C-27), 18.6 (C-28), 20.6 (C-29), 26.7 (C-30);27-Glc(inner): 101.8 (C-1′), 84.2 (C-2′), 78.6 (C-3′),71.8 (C-4′), 78.4 (C-5′), 63.1 (C-6′); 26-Glc(terminal):106.8 (C-1′′), 77.3(C-2′′), 79.0 (C-3′′), 71.9 (C-4′′),78.7 (C-5′), 62.9 (C-6′′)。以上數(shù)據(jù)與文獻報道一致[6],故鑒定化合物8為短柄雪膽苷A。
化合物9:白色粉末,易溶于甲醇。ESI-MSm/z:511.340 9 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.24 (3H, s, H-18), 1.27 (3H, s, H-19), 1.62 (3H, s,H-28), 1.12 (3H, s, H-29), 1.41 (3H, s, H-30), 1.55(3H, s, H-21), 1.51 (3H, s, H-26), 1.51 (3H, s, H-27),3.71 (1H, s, H-3), 5.25 (1H, m, H-16), 5.66 (1H, s,H-6);13C-NMR (150 MHz, pyridine-d5)δ: 21.0 (C-1),29.7 (C-2), 75.3 (C-3), 41.7 (C-4), 141.2 (C-5), 118.8(C-6), 24.1 (C-7), 43.3 (C-8), 49.2 (C-9), 35.7 (C-10),214.6 (C-11), 49.8 (C-12), 50.9 (C-13), 48.5 (C-14),46.7 (C-15), 71.9 (C-16), 59.4 (C-17), 20.3 (C-18),20.1 (C-19), 74.3 (C-20), 27.0 (C-21), 47.9 (C-22),123.0 (C-23), 143.0 (C-24), 69.6 (C-25), 30.6 (C-26),30.5 (C-27), 18.8 (C-28), 27.7 (C-29), 26.1 (C-30)。以上數(shù)據(jù)與文獻報道一致[9],故鑒定化合物9為cucurbitacin V。
化合物10:白色粉末,易溶于甲醇。ESI-MSm/z:639.472 5 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 0.70 (3H, s, H-18), 1.16 (3H, s, H-19), 0.85 (3H, d,J= 6.0 Hz, H-21), 0.98 (3H, s, H-28), 1.10 (3H, s,H-29), 1.56 (3H, s, H-30), 3.63 (1H, s, H-3), 5.52 (1H,d,J= 6.0 Hz, H-6), 6.46 (1H, t,J= 7.2 Hz, H-24),9.55 (2H, s, H-26), 1.79 (3H, s, H-27), 4.87 (1H, d,J=7.8 Hz, Glc-H-1');13C-NMR (150 MHz, pyridine-d5)δ: 22.6 (C-1), 28.4 (C-2), 87.6 (C-3), 42.4 (C-4), 141.6(C-5), 118.9 (C-6), 24.5 (C-7), 44.3 (C-8), 49.5 (C-9),36.3 (C-10), 214.0 (C-11), 49.1 (C-12), 49.3 (C-13),50.0 (C-14), 34.9 (C-15), 28.9 (C-16), 49.9 (C-17),17.3 (C-18), 20.7 (C-19), 36.4 (C-20), 18.7 (C-21),35.2 (C-22), 24.8 (C-23), 145.6 (C-24), 139.7 (C-25),195.5 (C-26), 9.6 (C-27), 18.6 (C-28), 28.7 (C-29),26.3 (C-30), 107.8 (C-1′), 76.0 (C-2′), 79.2 (C-3′),72.1 (C-4′), 78.7 (C-5′), 63.4 (C-6′)。以上數(shù)據(jù)與文獻報道一致[3],故鑒定化合物10為hemslepenside A。
化合物11:白色無定型粉末,易溶于甲醇。525.325 7 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.26 (3H, s, H-18), 1.22 (3H, s, H-19), 1.42 (3H, s,H-21), 1.97 (3H, s, H-26), 1.36 (3H, s, H-28), 1.28(3H, s, H-29), 1.47 (3H, s, H-30), 4.10 (1H, m, H-2),3.40 (1H, d,J= 9.0 Hz, H-3), 5.71 (1H, d,J= 6.0 Hz,H-6), 5.14 (1H, m, H-16), 5.09 (1H, m, H-23), 6.68(1H, d,J= 6.0 Hz, H-24), 4.52 (1H, s, H-27a), 4.58(1H, s, H-27b);13C-NMR (150 MHz, pyridine-d5)δ:35.2 (C-1), 71.3 (C-2), 81.7 (C-3), 43.2 (C-4), 142.8(C-5), 119.0 (C-6), 24.6 (C-7), 43.3 (C-8), 49.8 (C-9),34.6 (C-10), 213.4 (C-11), 49.2 (C-12), 49.0 (C-13),49.1 (C-14), 42.2 (C-15), 70.8 (C-16), 56.5 (C-17),20.4 (C-18), 21.2 (C-19), 72.7 (C-20), 30.5 (C-21),47.2 (C-22), 71.4 (C-23), 129.4 (C-24), 139.1 (C-25),21.4 (C-26), 61.3 (C-27), 22.3 (C-28), 22.7 (C-29),25.8 (C-30)。以上數(shù)據(jù)與文獻報道一致[8],故鑒定化合物11為jinfushanencin F。
化合物12:白色粉末,易溶于甲醇。ESI-MSm/z:819.926 3 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.21 (3H, s, H-18), 1.23 (3H, s, H-19), 1.68 (3H, s,H-21), 1.89 (3H, s, H-27), 1.29 (3H, s, H-28), 1.31(3H, s, H-29), 1.52 (3H, s, H-30), 3.66 (1H, s, H-3),5.46 (1H, d,J= 6.0 Hz, H-6), 4.90 (2H, d,J= 7.8 Hz H-26), 5.48 (1H, t,J= 7.2 Hz, H-24);13C-NMR (150 MHz, pyridine-d5)δ: 22.3 (C-1), 28.6 (C-2), 87.2(C-3), 42.1 (C-4), 141.6 (C-5), 118.9 (C-6), 25.0(C-7), 43.8 (C-8), 49.0 (C-9), 36.1 (C-10), 214.2(C-11), 49.2 (C-12), 49.8 (C-13), 50.1 (C-14), 34.9(C-15), 22.4 (C-16), 51.1 (C-17), 19.1 (C-18), 20.4(C-19), 74.2 (C-20), 26.1 (C-21), 44.7 (C-22), 23.1(C-23), 130.3 (C-24), 132.3 (C-25), 75.2 (C-26), 14.2(C-27), 19.1 (C-28), 28.1 (C-29), 26.7 (C-30); 3-Glc:107.9 (C-1′), 75.9 (C-2′), 79.1 (C-3′), 72.1 (C-4′), 78.6(C-5′), 63.4 (C-6′); 26-Glc: 103.4 (C-1′′), 75.6 (C-2′′),79.1 (C-3′′), 72.1 (C-4′′), 78.2 (C-5′′), 63.2 (C-6′′),以上數(shù)據(jù)與文獻報道一致[9],故鑒定化合物12為scandenoside R3。
化合物13:白色粉末,易溶于甲醇。ESI-MSm/z:657.401 2 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.07 (3H, s, H-18), 1.26 (3H, s, H-19), 1.53 (3H, s,H-21), 1.85 (1H, s, H-26), 1.13 (3H, s, H-28), 1.34(3H, s, H-29), 1.46 (3H, s, H-30), 4.23 (2H, s, H-27),3.62 (1H, s, H-3) , 5.47 (1H, d,J= 5.4 Hz, H-6), 5.85(1H, t,J= 7.2 Hz, H-24);13C-NMR (150 MHz,pyridine-d5)δ: 22.5 (C-1), 29.0 (C-2), 87.7 (C-3), 42.2(C-4), 141.7 (C-5), 118.9 (C-6), 24.6 (C-7), 42.5(C-8), 49.2 (C-9), 36.1 (C-10), 213.6 (C-11), 49.2(C-12), 49.3 (C-13), 50.0 (C-14), 34.6 (C-15), 22.5(C-16), 51.8 (C-17), 18.2 (C-18), 20.5 (C-19), 72.9(C-20), 26.3 (C-21), 45.3 (C-22), 23.6 (C-23), 128.1(C-24), 136.5 (C-25), 21.0 (C-26), 61.3 (C-27), 18.4(C-28), 28.6 (C-29), 26.3 (C-30), 3-Glc: 107.9 (C-1′),75.9 (C-2′), 79.2 (C-3′), 72.9 (C-4′), 78.7 (C-5′), 63.4(C-6′),以上數(shù)據(jù)與文獻報道一致[10],故鑒定化合物13為scandenoside R2。
化合物14:白色粉末,易溶于甲醇。ESI-MSm/z:601.416 7 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.28 (3H, s, H-18), 1.52 (3H, s, H-19), 1.76 (3H, s,H-21), 1.50 (3H, s, H-26), 1.51 (3H, s, H-27), 1.48(3H, s, H-28), 1.34 (3H, s, H-29), 1.61 (3H, s, H-30),1.90 (3H, s, COCH3-25), 3.50 (1H, d,J= 9.0 Hz,H-3), 4.17 (1H, m, H-2), 4.51 (1H, s, H-7), 4.92 (1H,t,J= 7.2 Hz, H-16), 6.25 (1H, d,J= 5.4 Hz, H-6);13C-NMR (150 MHz, pyridine-d5)δ: 34.4 (C-1), 70.7(C-2), 81.0 (C-3), 42.8 (C-4), 145.0 (C-5), 122.2(C-6), 65.9 (C-7), 52.8 (C-8), 50.1 (C-9), 35.1 (C-10),213.3 (C-11), 49.2 (C-12), 47.7 (C-13), 50.1 (C-14),46.3 (C-15), 70.1 (C-16), 58.7 (C-17), 22.7 (C-18),21.8 (C-19), 79.9 (C-20), 25.1 (C-21), 214.9 (C-22),32.0 (C-23), 35.2 (C-24), 81.4 (C-25), 25.7 (C-26),25.8 (C-27), 19.3 (C-28), 20.1 (C-29), 25.3 (C-30)170.0 (-OOCCH3), 22.0 (-OOCCH3)。以上數(shù)據(jù)與文獻報道一致[4],故鑒定化合物14為巨花雪膽G。
化合物15:白色粉末,易溶于甲醇。ESI-MSm/z:659.416 7 [M+Na]+。1H-NMR (600 MHz,pyridine-d5)δ: 0.85 (3H, s, H-18), 1.30 (3H, s, H-19),0.91 (3H, d,J= 6.0 Hz, H-21), 0.87 (3H, s, H-28),1.15 (3H, s, H-29), 1.56 (3H, s, H-30), 4.72 (2H, d,J=7.8 Hz, H-26), 4.72 (2H, d,J= 7.8 Hz, H-27), 3.66(1H, s, H-3) , 4.19 (1H, m, H-11), 5.49 (1H, d,J= 6.0 Hz, H-6), 5.90 (1H, t,J= 7.2 Hz, H-24);13C-NMR(150 MHz, pyridine-d5)δ: 27.2 (C-1), 30.0 (C-2), 88.4(C-3), 42.8 (C-4), 144.7 (C-5), 118.9 (C-6), 25.0(C-7), 43.9 (C-8), 40.5 (C-9), 36.6 (C-10), 78.6(C-11), 41.5 (C-12), 47.8 (C-13), 50.2 (C-14), 34.9(C-15), 28.7 (C-16), 51.0 (C-17), 17.4 (C-18), 26.7(C-19), 37.3 (C-20), 19.7 (C-21), 37.4 (C-22), 25.0(C-23), 128.1 (C-24), 141.2 (C-25), 65.8 (C-26), 58.9(C-27), 19.1 (C-28), 28.1 (C-29), 26.8 (C-30), 107.9(C-1′), 75.9 (C-2′), 79.1 (C-3′), 72.2 (C-4′), 78.2(C-5′), 63.4 (C-6′)。以上數(shù)據(jù)與文獻報道一致[11],故鑒定化合物15為Jinfushanoside A。
化合物16:白色無定形粉末,易溶于甲醇。ESI-MSm/z: 541.500 0 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.20 (3H, s, H-18), 1.45 (3H, s,H-29), 1.23 (3H, s, H-28), 1.60 (3H, s H-26), 1.50(3H, s, H-27), 1.29 (3H, s, H-19), 1.43 (3H, s, H-30),1.47 (3H, s, H-21), 3.43 (1H, d,J= 9.0 Hz, H-3), 4.16(1H, m, H-2), 4.92 (1H, m, H-16), 5.72 (1H, d,J= 5.4 Hz, H-6), 6.50 (1H, d,J= 15.6 Hz, H-23), 7.54 (1H, d,J= 15.6 Hz, H-24);13C-NMR (150 MHz, pyridine-d5)δ: 34.8 (C-1), 71.4 (C-2), 81.9 (C-3), 43.2 (C-4), 142.9(C-5), 119.1 (C-6), 24.6 (C-7), 43.6 (C-8), 49.6 (C-9),35.1 (C-10), 213.7 (C-11), 49.2 (C-12), 49.2 (C-13),51.6 (C-14), 43.2 (C-15), 70.9 (C-16), 59.6 (C-17),20.8 (C-18), 21.0 (C-19), 79.7 (C-20), 26.0 (C-21),204.7 (C-22), 121.2 (C-23), 156.0 (C-24), 70.7 (C-25),30.4 (C-26), 30.2 (C-27), 19.5 (C-28), 22.9 (C-29),25.9 (C-30)。以上數(shù)據(jù)與文獻報道一致[12],故鑒定化合物16為cucurbitacine F。
化合物17:白色粉末,易溶于甲醇。ESI-MSm/z:583.416 7 [M+Na]+。1H-NMR (600 MHz, pyridine-d5)δ: 1.17 (3H, s, H-18), 1.32 (3H, s, H-29), 1.24 (3H, s,H-28), 1.53 (3H, s H-26), 1.52 (3H, s, H-27), 1.20(3H, s, H-19), 1.49 (3H, s, H-30), 1.50 (3H, s, H-21),3.43 (1H, d,J= 9.0 Hz, H-3), 4.14 (1H, m, H-2), 5.85(1H, t,J= 7.8 Hz, H-16), 5.73 (1H, d,J= 5.4 Hz,H-6), 7.46 (1H, d,J= 15.0 Hz, H-23), 7.54 (1H, d,J=15.0 Hz, H-24);13C-NMR (150 MHz, pyridine-d5)δ:35.1 (C-1), 71.4 (C-2), 81.8 (C-3), 44.0 (C-4), 142.9(C-5), 119.0 (C-6), 24.4 (C-7), 43.0 (C-8), 48.7 (C-9),34.7 (C-10), 213.0 (C-11), 49.1 (C-12), 49.4 (C-13),51.0 (C-14), 43.3 (C-15), 74.9 (C-16), 55.7 (C-17),20.8 (C-18), 20.6 (C-19), 79.3 (C-20), 25.0 (C-21),204.3 (C-22), 120.2 (C-23), 157.2 (C-24), 70.7 (C-25),30.3 (C-26), 30.3 (C-27), 23.0 (C-28), 26.0 (C-29),19.3 (C-30), 170.7 (-OOCCH3), 21.6 (-OOCCH3)。以上數(shù)據(jù)與文獻報道一致[13],故鑒定化合物17為16-O-acetyl-cucurbitacin F。
將人宮頸癌HeLa細胞接種于96孔培養(yǎng)板中,每孔100 μL,37 ℃培養(yǎng)箱靜置培養(yǎng)24 h。給藥組加入100 μL不同質量濃度的樣品,樣品終質量濃度分別為100.0、50.0、10.0、5.0、1.0、0.5、0.1 μg/mL,每個質量濃度平行3個復孔??瞻讓φ战M給予含DMSO的完全培養(yǎng)基繼續(xù)培養(yǎng),多柔比星(IC50=0.24 μmol/L)為陽性對照組。培養(yǎng)24 h后,每孔加入5 mg/mL的MTT溶液20 μL,4 h后終止培養(yǎng)。將孔內(nèi)培養(yǎng)液小心吸出,每孔加入150 μL DMSO,置搖床上低速振蕩10 min,使結晶物充分溶解。用酶標儀在570 nm處測定各孔吸光度(A)值。
實驗結果顯示,化合物1、5、10、14、16~17對HeLa細胞有良好的細胞毒活性,IC50分別為5.07、7.13、3.53、3.79、6.49、2.82 μmol/L(表2)。
表2 化合物1~17對HeLa細胞的抗腫瘤活性Table 2 Antitumor activity of compounds 1—17 on HeLa cell lines
雪膽單體化合物抗HeLa細胞增殖試驗結果表明部分化合物具有抑制HeLa細胞增殖活性。通過對比試驗數(shù)據(jù),化合物的抗腫瘤活性與結構存在一定的構效關系。
葫蘆烷三萜皂苷元的活性要強于單糖苷、雙糖苷[14],如化合物1、14的IC50值小于化合物3、12等含糖單元化合物。當化合物C-16位與C-23位通過醚鍵成環(huán)時,細胞毒活性降低或消失。如化合物4、11,IC50值分別為22.5、55.4 μmol/L,化合物3、8的IC50值均大于100 μmol/L。當化合物C-11位取代基由羰基變?yōu)榱u基時,化合物的細胞毒活性降低或消失[15],如化合物8、15的IC50值均大于100 μmol/L,化合物2、6的IC50值在20~100 μmol/L。當化合物C-2、C-3位有羥基時,細胞毒活性增強,如化合物6的活性強于15。當化合物C-26位存在醛基時,化合物的細胞毒性增強[16],如化合物10的IC50值為3.53 μmol/L。
利益沖突所有作者均聲明不存在利益沖突