白永花,宋啟示
1中國(guó)科學(xué)院西雙版納熱帶植物園 熱帶植物資源開放實(shí)驗(yàn)室,昆明 650223;2中國(guó)科學(xué)院大學(xué),北京 100049
馬比木(Nothapodytes pittosporoides)為茶茱萸科假柴龍樹屬(Nothapodytes sp.)植物,又名海桐假柴龍樹、公黃珠子、追風(fēng)傘。馬比木為灌木,分布于貴州、湖南、湖北、四川等地。入藥能祛風(fēng)除濕、理氣散寒,主治風(fēng)寒濕痹、浮腫、疝氣。馬比木植株中含有大量喜樹堿及喜樹堿的甲氧基衍生物[1],喜樹堿具有較好的抗腫瘤活性,已經(jīng)成為了抗腫瘤藥物的主要成分之一。馬比木根中的喜樹堿含量最高,而細(xì)根中的喜樹堿含量最高可達(dá)0.53%,主根次之,莖、枝、葉、花序、果實(shí)和種子也含有喜樹堿,為極具價(jià)值的抗腫瘤藥物資源[2]。假柴龍樹屬有7 個(gè)種,該屬植物的化學(xué)成分研究目前報(bào)道的只有青脆枝和假柴龍樹,而對(duì)青脆枝的研究較多,分離到的化合物主要為喜樹堿及其衍生物[3-6]。
本文對(duì)馬比木根的化學(xué)成分進(jìn)行了研究,分離鑒定了14 個(gè)化合物,其中5 個(gè)為甾體類成分,2 個(gè)為三萜類成分,7 個(gè)為生物堿類成分。分別為:β-谷甾醇(1),β-胡蘿卜苷(2),7-酮基-β-谷甾醇(3),βsitosteryl-3-O-β-D-glucopyranoside-2'-O-palmitate (4),5α,6β-二羥基胡蘿卜苷(5),羽扇豆醇(6),3-乙酰氧基-12-齊墩果烯-28 醇(7),喜樹堿(8),9-甲氧基喜樹堿(9),10-羥基基喜樹堿(10),9-methoxy-mappicine-20-O-β-D-glucopyranoside(11),mappicine-20-O-β-D-glucopyranoside(12),(3S)-pumiloside(13),(-)-(3S)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid(14)。化合物1~7、9~14 為首次從該植物中分離得到。
熔點(diǎn)在XTRC-1 顯微熔點(diǎn)測(cè)定儀上測(cè)定;核磁共振譜用Bruker AV-400、DRX-500 及Avance Ⅲ-600 超導(dǎo)核磁共振儀測(cè)定,TMS 為內(nèi)標(biāo);EI-MS 用Waters AutoSpec Premier P776 雙聚焦三扇形磁質(zhì)譜儀測(cè)定;柱層析硅膠(200~300 目)及薄板層析硅膠(GF254)均為青島海洋化工廠生產(chǎn);MCI 為日本三菱化學(xué)株式會(huì)社生產(chǎn);凝膠材料使用GE Healthcare 的Sephadex LH -20。所用有機(jī)試劑均為分析純。
馬比木(Nothapodytes pittosporoides)根于2011年10 月采于湖南省鳳凰縣,并由中國(guó)科學(xué)院西雙版納熱帶植物園宋啟示研究員鑒定,標(biāo)本存放在中國(guó)科學(xué)院西雙版納熱帶植物園民族藥研究組實(shí)驗(yàn)室。
將馬比木根晾干,粉碎,稱重得84 kg。用90%甲醇加熱回流提取3 次(4,3,3 h)。合并提取液,減壓濃縮得甲醇浸膏4752 g,本實(shí)驗(yàn)取用4252 g。將浸膏用水?dāng)嚢枞芙庀♂尯笠来斡檬兔?、氯仿、正丁醇萃取,每種溶劑各萃取3 次,得到石油醚萃取物107 g,氯仿萃取物145 g,正丁醇萃取物622 g。石油醚部分經(jīng)硅膠柱(200~300 目)層析,以石油醚-丙酮梯度洗脫(100∶0,90∶10,80∶20,60∶40,50∶50,0∶100)得到六個(gè)粗組份(A1-A6);A2 經(jīng)硅膠柱層析(石油醚-丙酮梯度洗脫)和Sephadex LH-20(氯仿-甲醇洗脫)純化,得到化合物6(52 mg),7(46 mg);A4 經(jīng)反復(fù)硅膠柱層析和Sephadex LH-20(氯仿-甲醇洗脫)純化,得到化合物5(56 mg)。氯仿部分經(jīng)硅膠柱(200~300 目)層析,以石油醚-丙酮(90∶10,70∶30,60∶40,50∶50,30∶70,10∶90)梯度洗脫,得到六個(gè)粗組份(B1-B6);B1 經(jīng)硅膠柱層析(石油醚-丙酮梯度洗脫),其中第一個(gè)組份(5%丙酮-石油醚)經(jīng)重結(jié)晶得化合物1(800 mg);B2 經(jīng)反復(fù)硅膠柱層析和Sephadex LH-20 純化,得到化合物2(75 mg),3(52 mg),4(33 mg);B3 和B5 部分經(jīng)反復(fù)硅膠柱層析、MCI、重結(jié)晶和Sephadex LH-20 純化,從B3 部分得到化合物8(900 mg),9(560 mg),B5 部分得到化合物11(8 mg)。正丁醇部分上大孔樹脂分段,分別以10%、30%、50%、80%、95%比例的甲醇/水溶液和丙酮梯度洗脫得到六個(gè)組份(C1-C6);C3 部分經(jīng)MCI 柱層析和Sephadex LH-20 純化,得到化合物12(67 mg),14(46 mg);C4 經(jīng)MCI 柱層析、重結(jié)晶和Sephadex LH-20 純化,得到化合物10(45 mg),13(75 mg)。
化合物1 無色針晶(氯仿),mp.136~138 ℃,分子式為C29H50O。其1H NMR 圖譜與β-谷甾醇的標(biāo)準(zhǔn)圖譜完全一致,TLC 上的斑點(diǎn)位置及顯色均相同,與β-谷甾醇標(biāo)準(zhǔn)品混合熔點(diǎn)不下降,所以化合物1 鑒定為β-谷甾醇。
化合物2 白色粉末(甲醇),mp.283~284 ℃,分子式為C35H60O6。其1H NMR 圖譜與β-胡蘿卜苷的標(biāo)準(zhǔn)圖譜完全一致,TLC 上的斑點(diǎn)位置及顯色均相同,與β-胡蘿卜苷標(biāo)準(zhǔn)品混合熔點(diǎn)不下降,所以化合物2 鑒定為β-胡蘿卜苷。
化合物3 白色粉末(甲醇),mp.120~123 ℃,分子式為C29H48O2。1H NMR(CDCl3,400 MHz)δ:0.68(3H,s,H-18),0.92(3H,d,J=6.3 Hz,H-21),1.20(3H,s,H-19),2.03(1H,d,J=12.6 Hz,H-12b),2.24(1H,t,J=11.2 Hz,H-8),2.51(1H,d,J=10.8 Hz,H-4a),3.68(1H,t,J=11.0 Hz,H-3),5.69(1H,s,H-6);13C NMR(CDCl3,100 MHz)δ:11.93(C-18,C-29),17.27(C-19),18.88(C-21),18.98(C-26),19.78(C-27),21.17(C-11),22.98(C-28),25.97(C-23),26.29(C-15),28.53(C-16),29.03(C-25),31.13(C-2),33.87(C-22),36.05(C-20),36.28 (C-1),38.24 (C-10),38.63 (C-12),41.75(C-4),43.04(C-13),45.36(C-8),45.74(C-24),49.85(C-9,C-14),54.62(C-17),70.48(C-3),126.08(C-6),165.11(C-5),202.40(C-7)。以上數(shù)據(jù)與文獻(xiàn)[7]報(bào)道一致,故鑒定化合物3 為7-酮基-β-谷甾醇。
化合物4 白色無定形粉末,mp.151~154 ℃,分子式為 C51H90O7。EI-MS m/z:414[M-CH3(CH2)14COOC6H10O4]+,256[C16H32O2]+,239[C15H31CO]+,129,73,碎片峰中的系列峰與棕櫚酸EIMS 圖譜一致,顯示含有棕櫚酸。1H NMR(CDCl3,400 MHz)δ:0.88(3H,m,H-21),0.94(3H,s,H-19),1.21(18H,br s,H-5″~13″),3.27(1H,m,H-3),5.29(1H,s,H-6);13C NMR(CDCl3,100 MHz)δ:11.71(C-18),11.80(C-29),18.65(C-21),18.88(C-26),19.22(C-19),19.66(C-27),20.97(C-11),22.92(C-28),24.19(C-15),26.08(C-23),28.13(C-16),29.00(C-25),29.61(C-2),31.73(C-8),31.83(C-7),33.80(C-22),36.08(C-20),36.53(C-10),37.19(C-1),38.75(C-4),39.68(C-12),42.20(C-13),45.65(C-24),50.05(C-9),56.10(C-17),56.67(C-14),79.72(C-3),121.81(C-6),140.30(C-5),63.83(C-6'),70.48(C-4'),73.15(C-2'),73.48(C-5'),76.26(C-3'),101.24(C-1'),13.98(C-16″),22.58(C-15″),24.98(C-3″),29.72(C-4″~C-13″),29.77(C-14″),34.19(C-2″),173.94(C-1″)。以上數(shù)據(jù)與文獻(xiàn)[8]報(bào)道一致,故鑒定化合物4 為β-sitosteryl-3-O-β-D-glucopyranoside-2'-O-palmitate。
化合物5 白色粉末(甲醇),mp.296~298 ℃,分子式為C35H62O8。1H NMR(C5D5N,600 MHz)δ:0.73(3H,s,H-18),0.83-0.90(9H,m,H-26,27,29),0.99(3H,m,H-21),2.51(1H,dd,J=4.5,12.7 Hz,H-4b),2.96(1H,m,H-4a),4.17(1H,br s,H-6),5.68(1H,s,H-3),3.76(1H,m,H-5'),4.08(1H,m,H-2'),4.22(1H,t,J=9.0 Hz,H-4'),4.42(1H,dd,J=5.1,11.9 Hz,H-6'b),4.52(1H,dd,J=2.2,11.9 Hz,H-6'a),4.98(1H,d,J=7.7 Hz,H-1');13C NMR(C5D5N,150 MHz)δ:12.61(C-29),12.83(C-18),17.49(C-19),19.45(C-21),19.67(C-26),20.47(C-27),22.16(C-11),23.80(C-28),25.13(C-15),26.84(C-23),29.15(C-16),29.85(C-25),30.31(C-2),31.66(C-8),33.54(C-1),34.64(C-22),36.11(C-7),37.02(C-20),39.09(C-4),39.63 (C-10),41.06 (C-12),43.49 (C-13),46.26(C-9),46.47(C-24),56.98(C-14),57.03(C-17),75.40(C-3),75.99(C-5),76.80(C-6),63.16(C-6'),71.98(C-4'),75.80(C-2'),78.85(C-5'),79.08(C-3'),102.67(C-1')。以上數(shù)據(jù)與文獻(xiàn)[9]報(bào)道一致,故鑒定化合物5 為5α,6β-二羥基胡蘿卜苷。
化合物6 白色針狀結(jié)晶(丙酮),mp.215~216 ℃,分子式為C30H50O。1H NMR(CDCl3,400 MHz)δ:0.76(3H,s,H-24),0.78(3H,s,H-28),0.82(3H,s,H-25),0.94(3H,s,H-27),0.96(3H,s,H-23),1.02(3H,s,H-26),1.68(3H,s,H-30),3.19(1H,dd,J=11.1,4.8 Hz,H-3),4.56(1H,s,H-29a),4.68(1H,s,H-29b);13C NMR(CDCl3,100 MHz)δ:14.50(C-27),15.34(C-24),15.93(C-26),16.10(C-25),17.96(C-28),18.27(C-6),19.26(C-30),20.87(C-11),25.07(C-12),27.36(C-15),27.39(C-2),27.95(C-23),29.68(C-21),34.21(C-7),35.53 (C-16),37.11 (C-10),37.98 (C-13),38.64(C-1),38.82(C-4),39.96(C-22),40.77(C-8),42.78 (C-14),42.96 (C-17),47.95 (C-19),48.28(C-18),50.37(C-9),55.23(C-5),78.97(C-3),109.30(C-29),150.98(C-20)。以上數(shù)據(jù)與文獻(xiàn)[10]報(bào)道一致,故鑒定化合物6 為羽扇豆醇。
化合物7 白色結(jié)晶(丙酮),分子式為C32H52O3。1H NMR(CDCl3,400 Hz)δ:0.94(3H,s,H-27),0.96(3H,s,H-23),1.16(9H,s,30),2.05(3H,s,CH3COO),3.21(1H,d,J=10.9 Hz,H-28a),3.55(1H,d,J=10.9 Hz,H-28b),4.49(1H,m,H-3),5.19(1H,br s,H-12);13C NMR(CDCl3,100 MHz)δ:15.55(C-25),16.66(C-24),16.66(C-26),18.18(C-6),21.32(CH3C=O,),21.90(C-16),23.48(C-2,C-11,C-22),23.54(C-29),25.46(C-15),25.86(C-27),27.98(C-23),30.92(C-20),32.43(C-7),33.16(C-30),34.01(C-21),36.89(C-10),37.66(C-4),38.20(C-1),39.73(C-8),41.65(C-17),42.28(C-18),46.34(C-19),47.43(C-9),51.07(C-14),55.17 (C-50,69.70 (C-28),80.86 (C-3),122.23(C-12),144.16(C-13),171.06(C=O)。以上數(shù)據(jù)與文獻(xiàn)[11]報(bào)道一致,故鑒定化合物7 為3-乙酰氧基-12-齊墩果烯-28 醇。
化合物8 淺黃色針晶(氯仿),mp.265~270℃,分子式為C20H16N2O4。1H NMR(DMSO,400 MHz)δ:0.88(3H,t,J=7.0 Hz,H-18),1.86(2H,m,H-19),5.27(2H,s,H-5),5.42(2H,s,H-17),7.34(1H,s,H-14),7.70(1H,t,J=7.6 Hz,H-10),7.85(1H,t,J=7.5 Hz,H-11),8.11(1H,d,J=8.1 Hz,H-9),8.16(1H,d,J=8.4 Hz,H-12),8.68(1H,s,H-7);13C NMR(DMSO,100 MHz)δ:7.82(C-18),30.29(C-19),50.27(C-5),65.29(C-17),72.42(C-20),96.74(C-14),119.10(C-16),127.70(C-10),127.98(C-8),128.54(C-9),129.06(C-12),129.87(C-6),130.43(C-11),131.59(C-7),145.51(C-3),147.94 (C-13),150.03 (C-15),152.58 (C-2),156.86(C-16a),172.54(C-21)。以上數(shù)據(jù)與文獻(xiàn)[12]報(bào)道一致,故鑒定化合物8 為喜樹堿。
化合物9 淺黃色針晶(氯仿),mp.255~260℃分子式為C21H18N2O5。1H NMR(DMSO,500 MHz)δ:0.87(3H,t,J=7.3 Hz,H-18),1.86(2H,m,H-19),4.03(3H,s,OCH3),5.24(2H,s,H-5),5.42(2H,s,H-17),6.54(1H,s,OH),7.15(1H,d,J=7.6 Hz,H-10),7.31(1H,s,H-14),7.71(1H,d,J=8.5 Hz,H-12),7.76(1H,m,H-11),8.84(1H,s,H-7);13C NMR(DMSO,125 MHz)δ:7.70(C-18),30.38(C-19),50.44(C-5),56.14(OCH3),65.25(C-17),72.34(C-20),96.72(C-14),105.95(C-10),119.03(C-16),120.09(C-8),121.02(C-12),126.02(C-7),129.07(C-6),130.58(C-11),145.47(C-3),148.78(C-13),149.95(C-15),152.64(C-2),154.90(C-9),156.84(C-16a),172.39(C-21)。以上數(shù)據(jù)與文獻(xiàn)報(bào)道[3]一致,故鑒定化合物9 為9-甲氧基喜樹堿。
化合物10 淺黃色粉末,分子式為C20H16N2O5。1H NMR(DMSO,400 MHz)δ:0.86(3H,t,J=7.1 Hz,H-18),1.84(2H,m,H-19),5.21(2H,s,H-5),5.39(2H,s,H-17),7.24(1H,s,H-14),7.26(s,1H,H-9),7.40(1H,d,J=9.0 Hz,H-11),8.00(1H,d,J=9.1 Hz,H-12),8.43(1H,s,H-7);13C NMR(DMSO,100 MHz)δ:7.85(C-18),30.27(C-19),50.22(C-5),65.30(C-17),72.49(C-20),95.95(C-14),108.86(C-9),118.19(C-16),123.12(C-11),129.35(C-8),129.75(C-7),130.00(C-9),130.72(C-12),143.27(C-13),145.97(C-3),149.48(C-2),150.16(C-15),156.73(C-10),156.95(C-16a),172.65(C-21)。以上數(shù)據(jù)與文獻(xiàn)[13]報(bào)道一致,故鑒定化合物10 為10-羥基喜樹堿。
化合物11 淺黃色粉末,分子式為C26H30N2O8。EI-MS m/z:521[M+Na]+。1H NMR(DMSO,600 MHz)δ:0.85(3H,t,J=7.3 Hz,H-18),1.70~1.87(2H,m,H-19),2.15(3H,s,H-17),3.90(,1H,d,J=7.5 Hz,H-1'),4.03(3H,s,OCH3),5.21(2H,s,H-5),7.14(1H,d,J=7.7 Hz,H-10),7.35(1H,s,H-14),8.81(1H,s,H-7);13C NMR(DMSO,150 MHz)δ:9.77(C-18),11.95(C-17),28.45(C-19),50.49(C-5),56.22(OCH3),74.07(C-20),98.84(C-14),105.77(C-10),119.82(C-16),121.00(C-12),125.97(C-11),127.02(C-8),129.06(C-6),130.58(C-7),142.57(C-3),148.84(C-13),149.33(C-15),153.51(C-2),155.01(C-9),160.49(C-16a),61.25(C-6'),70.40(C-4'),73.67(C-2'),76.82(C-3'),77.34(C-5'),99.62(C-1')。根據(jù)文獻(xiàn)[3,6]報(bào)道,鑒定化合物11 為9-methoxy-mappicine-20-O-β-D-glucopyranoside。
化合物12 黃色粉末,分子式為C25H28N2O7。1H NMR(DMSO,600 MHz)δ:0.86(3H,t,J=7.1 Hz,H-18),1.73(1H,m,H-19),1.84(1H,m,H-19),2.17(3H,s,H-17),3.92(1H,d,J=7.4 Hz,H-1'),5.20(2H,d,J=10.7 Hz,H-5),7.34(1H,s,H-14),7.66(1H,t,J=7.4 Hz,H-10),7.81(1H,m,H-11),8.07(1H,d,J=8.1 Hz,H-9),8.12(1H,d,J=8.4 Hz,H-12),8.62(1H,s,H-7);13C NMR(DMSO,150 MHz)δ:9.80(C-18),11.97(C-17),28.48(C-19),50.22 (C-5),74.13 (C-20),98.88 (C-14),127.04 (C-16),127.43 (C-10),127.83 (C-8),128.63(C-9),128.94(C-12),129.73(C-6),130.37(C-11),131.50(C-7),142.56(C-3),147.97(C-13),149.40(C-15),153.36(C-2),160.50(C-16a),61.27(C-6'),70.42 (C-4'),73.69 (C-2'),76.85((C-3'),77.36(C-5'),99.66(C-1')。以上數(shù)據(jù)與文獻(xiàn)[3]報(bào)道一致,故鑒定化合物12 為mappicine-20-O-β-D-glucopyranoside。
化合物13 白色粉末,分子式為C26H28N2O8。1H NMR(DMSO,400 MHz)δ:2.01(1H,m,H-14),2.63(1H,m,H-20),2.99(1H,m,H-2'),3.16(2H,m,H-3',5'),3.68(1H,m,H-6'),4.31(1H,d,J=14.0 Hz,H-5),4.46(1H,d,J=13.6 Hz,H-5),4.53(1H,d,J=7.8 Hz,H-1'),4.74(1H,d,J=10.9 Hz,H-3),5.33(1H,d,J=11.6 Hz,H-18),5.44(1H,m,H-18),5.78(1H,m,H-19),7.04(1H,d,J=2.4 Hz,H-17),7.33((1H,t,J=7.4 Hz,H-10),7.59(1H,d,J=8.1 Hz,H-12),7.66(1H,m,H-11),8.11(1H,d,J=7.8 Hz,H-9),12.15(1H,s,N-H);13C NMR(DMSO,100 MHz)δ:23.67(C-15),28.17(C-14),43.62(C-20),47.53(C-5),59.47(C-3),94.81(C-21),108.62(C-16),113.02(C-6),118.40(C-12),120.63(C-18),123.36(C-10),124.78(C-9),125.29(C-8),131.24(C-11),132.46(C-19),140.39 (C-13),145.18 (C-17),149.84 (C-2),164.05(C-16a),173.07(C-7),61.10(C-6'),70.10(C-4'),73.19(C-2'),76.47(C-3'),77.32(C-5'),97.79(C-1')。以上數(shù)據(jù)與文獻(xiàn)[14]報(bào)道一致,故鑒定化合物13 為(3S)-pumiloside。
化合物14 白色粉末,分子式為C12H12N2O2。1H NMR(C5D5N,400 MHz)δ:3.71(2H,m,H-4),4.98(1H,m,H-3),5.42(2H,m,H-1);13C NMR(C5D5N,100 MHz)δ:24.03(C-4),41.92(C-1),56.95(C-3),106.84(C-4a),113.18(C-8),119.17(C-5),120.36(C-7),122.95(C-6),127.52(C-4b),128.27(C-9a),138.19(C-8a),173.71(COOH)。以上數(shù)據(jù)與文獻(xiàn)[15]報(bào)道一致,故鑒定化合物14 為(-)-(3S)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid。
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