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竹节参化学成分研究

2012-02-14张长春任晓慧任雪琴

天然产物研究与开发 2012年8期
关键词:波谱嘧啶硅胶

吴 兵,陈 新,张长春,任晓慧,任雪琴

武汉工业学院生物与制药工程学院,武汉430023

竹节参为五加科植物竹节参Panax japonicus C.A.Mey.的干燥根茎[1],又名竹节三七、竹节人参、白三七,主要分布于长江以南,西起云南西部,东至日本,且存在狭叶竹节参、珠子参等变种。竹节参具有滋补强壮、散瘀止痛、止血袪痰的功能,主要用于病后虚弱、劳嗽咯血、咳嗽痰多、跌扑损伤等症[1],对中枢神经系统、免疫系统、心血管系统具有药理作用[2]。竹节参的主要活性成分为皂苷类,并含少量挥发油、多糖和氨基酸等[2]。国内学者对竹节参的化学成分研究主要集中在三萜皂苷类化合物,而很少报道过嘌呤嘧啶类化合物,我们对竹节参进行了化学成分研究,分离鉴定了12个化合物:竹节参皂苷Ⅳa(1)、楤木皂苷A(2)、竹节参皂苷Ⅰb(3)、竹节参皂苷Ⅴ(4)、尿嘧啶(5)、胸嘧啶(6)、尿苷(7)、鸟苷(8)、胸苷(9)、腺苷(10)、肌苷(11)、胞苷(12),其中5~12为首次从该植物中分离。

1 仪器与材料

Bruker AM-600核磁共振光谱仪,ESI-MS(MDS Sciex Qstar)型质谱仪,BUCHI旋转蒸发仪,大孔吸附树脂(D101,天津市海光化工有限公司),MCI (CHP20P75-150 μm,Mitsubishi化工厂),葡聚糖凝胶Sephadex LH-20(美国Pharmacia公司),ODS(西安交大宝赛生物技术公司)柱层析硅胶(200~300目,青岛海浪硅胶干燥剂厂),高效薄层色谱层析板(青岛海洋化工厂)。

竹节参购自湖北恩施州中药材研究所竹节参种植基地,经武汉工业学院陈新教授鉴定为五加科植物竹节参Panax japonicas C.A.Mey的干燥根茎。

2 提取分离

干燥竹节参根茎5 kg,切片,粉碎,用90%乙醇25 L冷浸提取三次,每次一周,三次滤液分别浓缩后合并。依次用乙酸乙酯、正丁醇分别萃取三次,浓缩得到乙酸乙酯部位186 g,正丁醇部位208 g。乙酸乙酯部位和正丁醇部位合并一起上D101大孔树脂柱,乙醇-水溶液梯度洗脱,收集并浓缩得到两部分分别为Fr1、Fr2。Fr2上MCI柱,和反复硅胶柱色谱(三氯甲烷-甲醇-水 =4∶1∶20 μL-1∶3∶20 μL)得Fr3-2-1~6个部分,Fr3-2-1用溶剂系统甲醇-水重结晶2次,得化合物1(366 mg)。Fr3-2-3,上Sephadex LH-20柱用甲醇洗脱,得化合物2(678 mg)和5(211 mg)。Fr3-3-2上ODS柱用溶剂系统乙腈-水梯度洗脱,得到化合物3(1.856 g)、9(110 mg)和12(98 mg)。Fr3-3-3分别用溶剂系统乙腈-H2O梯度洗脱,得到化合物4(208mg)和10(60 mg)。将Fr1上MCI柱,和反复硅胶柱色谱(三氯甲烷-甲醇=20∶1~1∶1)得到流分 Fr4-1-1、Fr4-1-2、Fr4-2-1和 Fr4-3-14个部分。Fr4-1-1上Sephadex LH-20柱用甲醇洗脱,得到化合物6(20 mg)。Fr4-1-2、Fr4-2-1和Fr4-3-1分别上 ODS柱得到化合物7(5 mg)、8(10 mg)和11(15 mg)。

3 结构鉴定

竹节参皂苷Ⅳa(1)C47H74O18,ESI-MS中,m/ z 817.6[M+Na]+,793.8[M-H]-,推知化合物分子量为795。1H NMR(600 MHz,C5D5N)δ:1.36(1H,m,H-1a),0.78(2H,m,H-1b),2.32(1H,m,H-2a),1.83(1H,m,H-2b),3.32(1H,s,H-3),0.78(1H,m,H-5),1.48(1H,m,H-6a),1.34(1H,m,H-6b),1.77 (1H,m,H-7a),1.85(1H,m,H-7b),1.66(1H,m,H-9),1.99(1H,m,H-11a),2.08(1H,m,H-11b),5.42 (1H,br s,H-12),2.36(1H,m,H-15),1.27(1H,m,H-16a),1.88(1H,m,H-16b),3.19(1H,m,H-18),1.77(1H,m,H-19a),1.28(1H,m,H-19b),1.07 (1H,m,H-21a),1.35(1H,m,H-21b),1.45(1H,m,H-22a),0.94(1H,m,H-22b),1.31(3H,s,H-23),1.00(3H,s,H-24),0.83(3H,s,H-25),1.09(3H,s,H-26),1.29(3H,s,H-27),0.91(3H,s,H-29),0.89 (3H,s,H-30);28-O-Glc:6.32(1H,d,J=8.4Hz,H-1'),4.19(1H,m,H-2'),4.27(1H,m,H-3'),4.33 (1H,m,H-4'),4.01(1H,m,H-5'),4.38(1H,m,H-6'a),4.44(1H,m,H-6'b);3-O-GlcA:4.86(1H,brs,H-1''),4.28(1H,m,H-2''),4.36(1H,m,H-3''),4.17(1H,m,H-4''),3.98(1H,m,H-5'')。13C NMR (150 MHz,C5D5N)δ:38.3(C-1),25.4(C-2),87.9 (C-3),40.5(C-4),54.6(C-5),17.3(C-6),32.0(C-7),38.7(C-8),46.8(C-9),37.5(C-10),22.2(C-11),121.7(C-12),143.0(C-13),45.0(C-14),29.6 (C-15),22.2(C-16),45.8(C-17),40.9(C-18),46.8(C-19),31.3(C-20),35.7(C-21),32.8(C-22),27.0(C-23),14.3(C-24),15.8(C-25),16.3 (C-26),24.9(C-27),175.5(C-28),32.0(C-29),22.5(C-30);3-O-β-D-GlcA:106.0(C-1'),72.9(C-2'),76.6(C-3'),72.2(C-4'),77.6(C-5'),171.8 (C-6');28-β-D-Glc:94.5(C-1),74.3(C-2),76.9 (C-3),69.9(C-4),78.1(C-5),61.0(C-6)。以上波谱数据与文献[3]对照基本一致,故鉴定化合物1为竹节参Ⅳa。

楤木皂苷A(2) C47H74O18,ESI-MS中,m/z 949.7[M+Na]+,926.0[M-H]-,推知化合物分子量为927。1H NMR(600 MHz,C5D5N)δ:1.39(1H,m,H-1a),0.80(1H,m,H-1b),2.38(1H,m,H-2a),1.85(1H,m,H-2b),3.41(1H,s,H-3),0.82(1H,m,H-5),1.41(1H,m,H-6a),1.39(1H,m,H-6b),1.72 (1H,m,H-7a),1.89(1H,m,H-7b),1.68(1H,m,H-9),1.91(1H,m,H-11a),2.13(1H,m,H-11b),5.82 (1H,br s,H-12),2.86(1H,m,H-15),1.57(1H,m,H-16a),1.88(1H,m,H-16b),3.49(1H,m,H-18),1.97(1H,m,H-19a),1.58(1H,m,H-19b),1.07 (1H,m,H-21a),1.64(1H,m,H-21b),1.75(1H,m,H-22a),0.99(1H,m,H-22b),1.62(3H,s,H-23),1.33(3H,s,H-24),1.13(3H,s,H-25),1.49(3H,s,H-26),1.61(3H,s,H-27),1.21(3H,s,H-29),0.99 (3H,s,H-30);28-O-Glc:6.72(1H,d,J=8.4 Hz,H-1'),4.51(1H,m,H-2'),4.54(1H,m,H-3'),4.57 (1H,m,H-4'),4.31(1H,m,H-5'),4.68(1H,m,H-6'a),4.84(1H,m,H-6'b);3-O-GlcA:4.99(1H,brs,H-1''),4.53(1H,m,H-2''),4.62(1H,m,H-3''),4.47(1H,m,H-4''),4.28(1H,m,H-5'');Ara'(1→4):4.96(1H,d,H-1'''),4.93(1H,t,H-2'''),4.65 (1H,H-3'''),4.88(1H,br s,H-4'''),3.9(1H,d,H-5'''a),4.51(1H,d,H-5'''b);13C NMR(150 MHz,C5D5N)δ:38.3(C-1),25.4(C-2),87.9(C-3),40.5 (C-4),54.5(C-5),17.3(C-6),32.8(C-7),38.7(C-8),48.5(C-9),37.4(C-10),22.2(C-11),121.7(C-12),142.0(C-13),45.0(C-14),28.8(C-15),22.4 (C-16),45.8(C-17),40.9(C-18),46.8(C-19),31.3(C-20),35.7(C-21),32.0(C-22),27.0(C-23),15.7(C-24),14.3(C-25),16.3(C-26),24.9 (C-27),175.2(C-28),31.9(C-29),22.5(C-30);3-O-β-D-GlcA:105.9(C-1'),72.9(C-2'),74.1(C-3'),77.7(C-4'),75.0(C-5'),171.5(C-6');Ara'(1→4):107.3(C-1"),81.3(C-2"),75.3(C-3"),86.6(C-4"),61.4(C-5");28-β-D-Glc:94.6(C-1), 74.1(C-2),77.7(C-3),69.8(C-4),78.2(C-5),61.0(C-6)。以上波谱数据与文献[4]对照基本一致,故鉴定化合物2为楤木皂苷A。

竹节参皂苷Ⅰb(3)C47H74O18,ESI-MS m/z: 949.7[M+Na]+,926.0[M-H]-,推知化合物分子量为927。1H NMR(600 MHz,C5D5N)δ:1.31(1H,m,H-1a),0.62(1H,m,H-1b),2.22(1H,m,H-2a),1.68(1H,m,H-2b),3.11(1H,s,H-3),0.71(1H,m,H-5),1.39(1H,m,H-6a),1.22(1H,m,H-6b),1.65 (1H,m,H-7a),1.74(1H,m,H-7b),1.52(1H,m,H-9),1.91(1H,m,H-11a),2,14(1H,m,H-11b),5.33 (1H,br s,H-12),2.24(1H,m,H-15),1.15(1H,m,H-16a),1.75(1H,m,H-16b),3.05(1H,m,H-18),1.68(1H,m,H-19a),1.21(1H,m,H-19b),1.13 (1H,m,H-21a),1.31(1H,m,H-21b),1.39(1H,m,H-22a),0.91(1H,m,H-22b),1.39(3H,s,H-23),1.08(3H,s,H-24),0.78(3H,s,H-25),1.01(3H,s,H-26),1.22(3H,s,H-27),0.85(3H,s,H-29),0.81 (3H,s,H-30),3-O-GlcA:4.71(1H,br s,H-1'),4.12 (1H,m,H-2'),4.31(1H,m,H-3'),4.11(1H,m,H-4'),3.82(1H,m,H-5');Ara'(1→4):4.82(1H,d,H-1''),4.81(1H,t,H-2''),4.54(1H,H-3''),4.72 (1H,brs,H-4''),3.91(1H,d,H-5''a),4.49(1H,d,H-5''b);Glc''(1→6):4.86(1H,d,H-1'''),3.72 (1H,t,H-2'''),3.98(1H,H-3'''),4.18(1H,H-4'''),3.58(1H,H-5'''),4.01(1H,H-6'''a),4.13 (1H,H-6'''b);13C NMR(150 MHz,C5D5N)δ:38.4 (C-1),25.4(C-2),88.0(C-3),38.7(C-4),54.6(C-5),17.3(C-6),29.6(C-7),40.5(C-8),48.5(C-9),37.5(C-10),22.2(C-11),121.7(C-12),143.0(C-13),44.9(C-14),28.8(C-15),24.9(C-16),45.8 (C-17),40.9(C-18),46.8(C-19),31.3(C-20),35.7(C-21),32.0(C-22),27.0(C-23),15.1(C-24),14.4(C-25),16.2(C-26),26.6(C-27),175.3 (C-28),32.8(C-29),22.4(C-30);3-O-β-D-GlcA: 69.9(C-2'),75.4(C-3'),77.7(C-4'),76.6(C-5'); Ara'(1→4):105.8(C-1"),82.3(C-2"),77.2(C-3"),82.3(C-4");28-β-D-Glc:94.6(C-1),71.4(C-2),77.7(C-3),70.4(C-4),77.0(C-5),61.0(C-6)。以上波谱数据与文献[5]对照基本一致,故鉴定化合物3为竹节参皂苷Ⅰb。

竹节参皂苷Ⅴ(4) C48H76O19,ESI-MS m/z: 979.7[M+Na]+,956.0[M-H]-,推知化合物分子量为957。1H NMR(600 MHz,C5D5N)δ:1.39(1H,m,H-1a),0.72(1H,m,H-1b),2.21(1H,m,H-2a),1.81(1H,m,H-2b),3.29(1H,s,H-3),0.72(1H,m,H-5),1.41(1H,m,H-6a),1.32(1H,m,H-6b),1.69(1H,m,H-7a),1.79(1H,m,H-7b),1.60(1H,m,H-9),1.92(1H,m,H-11a),2.11(1H,m,H-11b),5.38(1H,br s,H-12),2.32(1H,m,H-15),1.21(1H,m,H-16a),1.82(1H,m,H-16b),3.17 (1H,m,H-18),1.73(1H,m,H-19a),1.25(1H,m,H-19b),1.11(1H,m,H-21a),1.39(1H,m,H-21b),1.41(1H,m,H-22a),0.98(1H,m,H-22b),1.35 (3H,s,H-23),1.06(3H,s,H-24),0.89(3H,s,H-25),1.13(3H,s,H-26),1.27(3H,s,H-27),0.94 (3H,s,H-29),0.91(3H,s,H-30);28-O-Glc:6.29 (1H,d,J=8.4Hz,H-1'),4.12(1H,m,H-2'),4.21 (1H,m,H-3'),4.28(1H,m,H-4'),4.03(1H,m,H-5'),4.19(1H,m,H-6'a),4.42(1H,m,H-6'b);3-OGlcA:4.71(1H,brs,H-1''),4.35(1H,m,H-2''),4.39(1H,m,H-3''),4.27(1H,m,H-4''),3.93(1H,m,H-5'');β-D-Glc:4.48(1H,H-1'''),3.86(1H,H-2'''),5.18(1H,H-3'''),5.01(1H,H-4'''),3.69 (1H,H-5'''a),4.12(1H,H-5'''b);13C NMR(150 MHz,C5D5N)δ:38.3(C-1),25.0(C-2),87.9(C-3),38.7(C-4),54.5(C-5),17.3(C-6),32.0(C-7),38.3(C-8),46.7(C-9),37.4(C-10),22.2(C-11),121.7(C-12),143.0(C-13),41.0(C-14),27.0(C-15),22.5(C-16),45.0(C-17),40.5(C-18),45.8 (C-19),29.6(C-20),35.7(C-21),32.8(C-22),27.0(C-23),14.4(C-24),15.6(C-25),16.3(C-26),25.0(C-27),175.3(C-28),31.3(C-29),22.5 (C-30);3-O-β-D-GlcA:97.6(C-1'),78.2(C-2'),71.6(C-3'),71.2(C-4'),76.0(C-5');β-D-Glc: 104.7(C-1"),76.3(C-2"),76.6(C-,3"),70.0(C-4"),73.0(C-5"),61.5(C-6");28-β-D-Glc:94.6 (C-1),71.4(C-2),77.7(C-3),70.4(C-4),77.0(C-5),61.0(C-6)。以上波谱数据与文献[6]对照基本一致,故鉴定化合物4为竹节参皂苷Ⅴ。

尿嘧啶(5) C4H4N2O2,1H NMR(600 MHz,DMSO-d6)δ:12.03(1H,br.s,H-3),11.91(1H,brs,H-1),7.49(1H,d,J=7.6 Hz,H-6),5.56(1H,d,J =7.6 Hz,H-5)。13C NMR(150 MHz,DMSO-d6)δ: 164.6(C-4),151.4(C-2),142.8(C-6),100,1(C-5)。以上波谱数据与文献[7]对照基本一致,故鉴定化合物5为尿嘧啶。

胸嘧啶(6) C5H6N2O2,1H NMR(600 MHz,CD3OD)δ:7.11(1H,s,H-6),1.76(3 H,s,5-CH3)。13C NMR(150 MHz,CD3OD)δ:166.3(C-4),152.8(C-2),137.1(C-6),109.3(C-5),10.9(5-CH3)。以上波谱数据与文献[7]对照基本一致,故鉴定化合物6为胸嘧啶。

尿苷(7) C9H12N2O6,1H NMR(600 MHz,CD3OD)δ:8.24(1H,d,J=8.0 Hz,H-6),6.13(1H,d,J=4.8 Hz,H-1'),5.95(1H,d,J=8.0 Hz,H-5),4.44(1H,m,H-3'),4.33(1H,m,H-2'),4.23(1H,dd,J=3.2,1.6 Hz,H-4'),3.99(1H,dd,J=12.4,3.2 Hz,H-5'a),4.01(1H,dd,J=12.4,2.8 Hz,H-5' b)。13C NMR(150 MHz,CD3OD)δ:164.1(C-4),151.8(C-2),141.6(C-6),101.2(C-5),89.9(C-1'),84.1(C-4'),74.2(C-3'),70.3(C-2'),61.3(C-5')。以上波谱数据与文献[7]对照基本一致,故鉴定化合物7为尿苷。

鸟苷(8) C10H13N5O5,1H NMR(600 MHz,D2O)δ:8.01(1H,s,H-8),5.63(1H,d,J=6.0 Hz,H-1'),4.80(1H,t,J=5.6 Hz,H-2'),4.55(1H,t,J =3.6Hz,H-3'),4.19(1H,d,J=3.2 Hz,H-4'),3.93(1H,dd,J=12.8,3.2 Hz,H-5'a),3.96(1H,dd,J=12.8,2.4 Hz,H-5'b)。13C NMR(150 MHz,D2O)δ:158.0(C-6),154.1(C-2),152.0(C-4),136.3(C-8),118.2(C-5),87.9(C-1'),86.4(C-4'),74.9 (C-3'),70.8(C-2'),61.5(C-5')。以上波谱数据与文献[7]对照基本一致,故鉴定化合物8为鸟苷。

胸苷(9)C10H9N2O5,1H NMR(600 MHz,DMSO-d6)δ:11.31(1H,br.s,NH),7.67(1H,s,H-6),6.18(1H,t,J=6.4,7.2 Hz,H-1'),4.21(1H,d,J= 3.6 Hz,H-3'),3.74(1H,m,H-4'),3.59(2H,m,H-5'),2.13(2H,dd,J=6.4,3.6 Hz,H-2'),1.69(3H,s,5-CH3)。13C NMR(150 MHz,DMSO-d6)δ:163.1 (C-4),149.9(C-2),136.0(C-6),109.1(C-5),86.9 (C-4'),84.0(C-1'),70.6(C-3'),61.4(C-5'),39.6 (C-2'),12.8(5-CH3)。以上波谱数据与文献[7]对照基本一致,故鉴定化合物9为胸苷。

腺苷(10) C10H13N5O4,1H NMR(600 MHz,DMSO-d6)δ:8.15(1H,s,H-8),7.99(1H,s,H-2),7.13(2H,brs,NH2),5.69(1H,d,J=6.0 Hz,H-1'),4.39(1H,d,J=5.2 Hz,H-2'),4.01(1H,m,H-3),3.82(1H,d,J=3.0 Hz,H-4'),3.51(1H,dd,J= 12.4,3.6 Hz,H-5'a),3.78(1H,dd,J=12.4,6.2 Hz,H-5'b)。13C NMR(150 MHz,DMSO-d6)δ:158.6 (C-6),154.2(C-2),151.1(C-4),141.9(C-8),123.0(C-5),89.3(C-1'),87.7(C-4'),75.8(C-2'),72.9(C-3'),63.5(C-5')。以上波谱数据与文献[7]对照基本一致,故鉴定化合物10为腺苷。

肌苷(11) C10H12N4O5,1H NMR(600 MHz,CD3OD)δ:8.04(1H,s,H-8),7.84(1H,s,H-2),5.78(1H,d,J=6.0Hz,H-1'),4.29(1H,dd,J= 5.4,4.6 Hz,H-2'),4.05(1H,t,J=4.4,3.2 Hz H-3'),3.99(1H,dd,J=6.0,3.0 Hz,H-4'),3.51(1H,dd,J=12.4,3.2 Hz,H-5'a),3.59(1H,dd,J=12.4,2.8 Hz,H-5'b)。13C NMR(150 MHz,CD3OD)δ: 157.6(C-6),149.0(C-2),147.3(C-4),139.6(C-8),124.1(C-5),87.2(C-1'),85.9(C-4'),74.0(C-3'),71.5(C-2'),62.8(C-5')。以上波谱数据与文献[7]对照基本一致,故鉴定化合物11为肌苷。

胞苷(12) C9H13N3O5,1H NMR(600 MHz,CD3OD)δ:8.,14(1H,d,J=7.2 Hz,H-6),6.03 (1H,d,J=7.2 Hz,H-5),5.83(1H,d,J=2.4 Hz,H-1'),4.29(2H,m,H-2',3'),4.05(1H,m,H-4'),3.90(1H,dd,J=12.2,3.0 Hz,H-5'a),3.90(1H,dd,J=12.4,2.6 Hz,H-5'b)。13C NMR(150 MHz,CD3OD)δ:167.8(C-4),158.9(C-2),144.3(C-6),96.0(C-5),93.1(C-1'),85.9(C-4'),76.0(C-3'),71.5(C-2'),62.8(C-5')。以上波谱数据与文献[7]对照基本一致,故鉴定化合物12为胞苷。

4 结果讨论

从干燥竹节参根茎中分离得到12个化合物,其中三萜皂苷类4个,嘌呤嘧啶类8个。研究表明竹节参总皂苷具有一定的抗氧化活性[8],可显著提高运动后小鼠肝脏、脑组织中超氧化物歧化酶(SOD)和谷胱甘肽(CSH)活性,降低丙二醛(MDA)含量[8]。大量实验研究结果表明嘌呤和嘧啶类化合物具有广泛的特异性作用[9],如短时程作用方面(神经信号传递、外分泌、内分泌和免疫功能调节),以及长时程作用方面(发育及再生过程中的细胞生长、分化和增生)[9]。

1 Chinese Pharmacopoeia Commission(国家药典委员会).Pharmacopoeia of the People’s Republic of China.Beijing: Chemical Industry Press,2005.93.

2 Liu J(刘娟),Wang LX(王良信).Textual research of Geranium wilfordii Maxim.Chin Tradit Herb Drugs(中草药),1992,23:276-277.

3 Viviane S,Pires,Dominique GU,et al.Saponins from Ilex dumosa,an Erva-maté(Ilex paraguariensis)Adulterating Plant.J Agric Food Chem,1997,45:1027-1031.

4 Jiang YT(姜永涛),Xu SX(徐绥绪),Chen YJ(陈英杰),et al.Chemical constituents of Aralia elata(Mip.)Seem.J Shenyang Pharm School(沈阳药学院学报),1991,8:265-268.

5Tang HF(汤海峰),Yi YH(易杨华),Wang ZZ(王忠壮),et al.Chemical constituents of root bark of Aralia taibaiensis.Chin Pharm J(中国药学杂志),1996,31:204-206.

6 Meng DL(孟大利),Li X(李铣),Xiong YH(熊印华),et al.Chemical constituents of traditional Chinese medicine Achyranthes bidentata.J Shengyang Pharm Univ(沈阳药科大学学报),2002,19:27-30.

7 Yu DQ(于德泉),Yang JS(杨峻山).Handbook of analytical chemistry(化学分析手册).Beijing:Chemical Industry Press,1999,7:621-908.

8 Qian LN(钱丽娜),Chen P(陈平),Li XL(李小莉),et al.Study on antioxidant activity of total saponins in Panax japonicas.J Wuhan Bot Res(武汉植物学研究),2008,26: 674-676.

9 Ren LM(任雷鸣),Zhang M(张淼).Physiological roles of the receptors for purines and pyrimidines.Chin Pharm Bull (中国药理学通报),2002,18:20-22.

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