陳雪林,盧志遠,貢潘偏抽,張玉梅*
1中國科學院西雙版納熱帶植物園熱帶植物資源可持續(xù)利用重點實驗室,昆明 650223;2中國科學院大學,北京 100049
五加科(Araliaceae)是藥用植物資源非常豐富的一個科[1],有很多著名的傳統(tǒng)藥材,如人參、三七等;還有很多民間常用的中草藥,如鵝掌藤、白簕等。刺通草(Trevesiapalmate(Roxb.)Vis.var.palmata)為五加科(Araliaceae)刺通草屬(Trevesia)植物,主要分布于云南南部、廣西上林和貴州貞豐[2]。目前針對刺通草屬的化學成分研究比較少,從中分離得到的化學成分主要是齊墩果酸型三萜皂苷化合物,對刺通草的生物活性主要集中在抗腫瘤、降血糖、抗炎和抗病毒等方面[3-7]。
刺通草作為傳統(tǒng)傣藥,傣族人民主要用其治療“風寒濕痹證”,且Nunziatina等[4]從刺通草中分離得到的三萜皂苷及其次皂甙元具有抑制細胞增殖的活性,這為其深度開發(fā)利用提供了科學依據(jù)。為進一步明確刺通草的化學成分及其抗腫瘤活性藥效物質基礎,以期為其刺通草在抗腫瘤方面的開發(fā)利用提供一定的理論依據(jù),本課題組以生長在中國云南省西雙版納地區(qū)的刺通草作為研究對象,對其化學成分及抗腫瘤活性進行研究。
核磁共振譜用Avance Ⅲ-600超導核磁共振儀測定,TMS為內標;ESI-MS用Water Auto Spec Premier雙聚焦三扇形磁質譜儀測定;R-1001VN型旋轉蒸發(fā)儀(鄭州長城科工有限公司);DLSB-5L/25型低溫冷卻液循環(huán)泵(鞏義市予華儀器有限公司);YP5001N型電子天平(2~5 000g)(上海舜宇恒平科學儀器有限公司);AL104型電子天平(0.000 0~110 g)(梅特勒-托利多儀器(上海)有限公司);SK52008型超聲波清洗器(上海科導超聲儀器有限公司);UV-1型三用紫外儀(上海顧村電光儀器);柱層析硅膠(80~100目,200~300目)及薄板層析硅膠(GF-254)均為青島海洋化工廠生產;Sephadex LH-20(美國Pharmacia公司);Rp-C18(德國Merk公司);高效液相色譜儀(漢邦科技公司);所用化學試劑均為工業(yè)重蒸試劑或分析純。
刺通草于2015年10月采于云南西雙版納,并由中國科學院西雙版納熱帶植物園肖春芬老師鑒定為Trevesiapalmate(Roxb.) Vis.var.palmata,標本(NO.20151006)存放在中國科學院西雙版納熱帶植物園創(chuàng)新藥物研究組實驗室。
將刺通草枝葉曬干,粉碎,稱重得18 kg。用90%甲醇于室溫分別提取3次(7天、3天、3天)。合并提取液,減壓濃縮,制成甲醇浸膏。甲醇浸膏用水攪拌溶解稀釋后,依次用石油醚、乙酸乙酯、正丁醇進行萃取,每種溶劑萃取四次,減壓回收溶劑后得到石油醚萃取物503 g,乙酸乙酯萃取物69.7 g,正丁醇萃取物208 g。石油醚部分經硅膠柱(200~300目,5 kg),以石油醚-丙酮(V/V=9∶1、8∶2、7∶3、6∶4、1∶1、0∶1)梯度洗脫,得到A1-A7七個組分;A2經反復重結晶得到化合物13(203 mg);A5經反復硅膠柱層析和Sephadex LH-20純化,得到化合物14(33 mg);乙酸乙酯部分經硅膠柱(200~300目,1.5 kg),以氯仿-甲醇(V/V=20∶1、10∶1、5∶1、2∶1、1∶1、0∶1)梯度洗脫,得到B1-B6六個組分;B2經反復硅膠柱層析, MCI和Sephadex LH-20純化,得到化合物1(93 mg);B3經反復硅膠柱層析和Sephadex LH-20純化,得到化合物12(13 mg);B5經反復硅膠柱層析,Rp-C18和Sephadex LH-20純化,得到化合物3(22 mg);B6經反復硅膠柱層析,Rp-C18和Sephadex LH-20純化,得到化合物2(15 mg); B7經反復硅膠柱層析,Rp-C18和Sephadex LH-20純化,得到化合物8(17 mg); 正丁醇部分經硅膠柱(200~300目,1.5 kg),以氯仿-甲醇(V/V=50∶1、20∶1、10∶1、5∶1、2∶1、1∶1、0∶1)梯度洗脫,洗脫得到C1~C7七個組分;C1經反復硅膠柱層析和Sephadex LH-20純化,得到化合物9(13 mg);C2經反復硅膠柱層析,Rp-C18和Sephadex LH-20純化,得到化合物10(15 mg);C4經反復硅膠柱層析和Sephadex LH-20純化,得到化合物11(22 mg);C5經反復硅膠柱層析,MCI和Sephadex LH-20純化,得到化合物7(5 mg);C6經反復硅膠柱層析,MCI,Rp-C18和 Sephadex LH-20純化,得到化合物4(7 mg)和5(7 mg);C7經反復硅膠柱層析,MCI和 Sephadex LH-20純化,得到化合物6(4 mg)?;衔?~14的化學結構見圖1。
采用MTS法[8]測定部分單體化合物對人腫瘤細胞株SMMC-7721、Hela、MCF-7的體外腫瘤細胞毒活性。用含10%胎牛血清的培養(yǎng)液(DMEM或者RMPI1640)配成單個細胞懸液,以每孔5 000個細胞接種到96孔板,每孔體積100 μL,細胞提前12~24 h接種培養(yǎng)。加入待測化合物溶液(化合物用DMSO溶解,化合物以100 μg/mL濃度初篩),每孔終體積200 μL,每種處理均設3個復孔。37 ℃培養(yǎng)48 h后,細胞棄孔內培養(yǎng)液,每孔加MTS溶液20 μL以及培養(yǎng)液100 μL;設3個空白復孔(MTS溶液20 μL和培養(yǎng)液100 μL的混合液),繼續(xù)孵育2~4 h,使反應充分進行。多功能酶標儀(MULTISKAN FC)測定492 nm處的OD值,計算得出抗腫瘤活性的抑制率。每次實驗均設順鉑(DDP)和紫杉醇(taxol)兩個陽性化合物,以濃度為橫坐標,細胞存活率為縱坐標繪制細胞生長曲線,應用兩點法計算化合物的IC50值。
具有抑制率超50%的待測樣品進行復篩,在測試濃度基礎上向下稀釋5個濃度,測定OD值,計算抑制率,求出相應的半數(shù)抑制濃度IC50。
抑制率=(1-實驗孔OD492 nm/空白孔OD492 nm)
×100%
圖1 化合物1~14的化學結構Fig.1 The chemical structures of compounds 1-14
IC50(50% concentration of inhibition)按Reed&Muench法計算。
化合物1白色粉末(甲醇);化學式為C41H66O12,ESI-MS:m/z749 [M-H]-;1H NMR(600 MHz,CD3OD)δ:5.24(1H,t,J=3.6 Hz,H-12),5.16(1H,d,J=1.2 Hz,H-1′),4.55(1H,d,J=5.4 Hz,H-l″),3.38(1H,dd,J=11.0,6.8 Hz,H-3),1.24(3H,d,J=6.0 Hz,H-6″),1.18(3H,s,H-27),0.98(3H,s,H-24),0.94(3H,s,26),0.91(3H,s,H-30),0.82(3H,s,H-25),0.70(3H,s,H-29);13C NMR(150 MHz,CD3OD)δ:39.8(C-1),26.7(C-2),82.4(C-3),44.1(C-4),48.2(C-5),18.1(C-6),34.0(C-7),40.7(C-8),48.4(C-9),37.8(C-10),24.7(C-11),123.8(C-12),145.4(C-13),43.1(C-14),29.0(C-15),24.1(C-16),47.8(C-17),42.9(C-18),47.4(C-19),31.8(C-20),35.0(C-21),33.5(C-22),64.7(C-23),13.9(C-24),16.5(C-25),17.9(C-26),26.6(C-27),182.1(C-28),33.7(C-29),24.2(C-30),104.5(C-1′),79.6(C-2′),76.8(C-3′),70.3(C-4′),65.0(C-5′),102.0(C-1″),72.2(C-2″),72.3(C-3″),74.1(C-4″),69.4(C-5″),19.0(C-6″)。以上數(shù)據(jù)與文獻[9]報道一致,鑒定為3-O-α-L-鼠李糖-(1→2)-α-L-阿拉伯糖常春藤苷。
化合物2白色針狀結晶(甲醇);化學式為C30H48O3,ESI-MS:m/z455 [M-H]-;1H NMR(600 MHz,CD3OD)δ:5.22(1H,t,J=3.6 Hz,H-12),3.15(1H,dd,J=11.4,4.2 Hz,H-3),1.16(3H,s,H-27),0.97(3H,s,H-23),0.94(6H,s,H-24,H-29),0.91(3H,s,H-30),0.82(3H,s,H-25),0.78(3H,s,H-26);13C NMR(150 MHz,CD3OD)δ:38.6(C-1),27.4(C-2),79.2(C-3),39.0(C-4),55.4(C-5),18.5(C-6),32.8(C-7),39.4(C-8),47.8(C-9),37.3(C-10),23.2(C-11),122.9(C-12),143.8(C-13),41.8(C-14),27.9(C-15),23.6(C-16),46.7(C-17),41.3(C-18),46.1(C-19),30.9(C-20),34.0(C-21),32.6(C-22),28.3(C-23),15.8(C-24),15.5(C-25),17.3(C-26),26.1(C-27),181.6(C-28),33.3(C-29),23.8(C-30)。以上數(shù)據(jù)與文獻[10]報道基本一致,鑒定為齊墩果酸。
化合物3白色針狀結晶(甲醇);化學式為C30H48O3,ESI-MS:m/z455 [M-H]-;1H NMR(600 MHz,CD3OD)δ:5.23(1H,t,J=3.5 Hz,H-12),3.15(1H,dd,J=11.6,4.5 Hz,H-3),1.09(3H,s,H-27),0.97(9H,overlapped,H-23,H-24,H-29),0.89(3H,d,J=6.4 Hz,H-30),0.85(3H,s,H-25),0.77(3H,s,H-26);13C NMR(150 MHz,CD3OD)δ:40.6(C-1),28.0(C-2),79.8(C-3),40.6(C-4),56.9(C-5),19.6(C-6),34.5(C-7),40.9(C-8),48.1(C-9),38.2(C-10),24.5(C-11),127.0(C-12),139.8(C-13),43.4(C-14),29.3(C-15),25.5(C-16),48.1(C-17),54.5(C-18),40.1(C-19),40.0(C-20),31.9(C-21),38.3(C-22),28.9(C-23),16.5(C-24),16.2(C-25),17.8(C-26),24.2(C-27),181.8(C-28),17.9(C-29),21.7(C-30)。以上數(shù)據(jù)與文獻[11]報道一致,鑒定為熊果酸。
化合物4白色粉末(甲醇);化學式為C53H86O22,ESI-MS:m/z1119 [M+2Na-H]-、749 [M-2Glc-H]-;1H NMR(600 MHz,CD3OD)δ:5.33(1H,d,J=8.2 Hz,H-1?),5.25(1H,brs,H-12),5.16(1H,s,H-1″),4.64(1H,s,H-l″″),4.55(1H,d,J=5.6 Hz,H-l′),3.25(1H,dd,J=5.6,1.9 Hz,H-3),1.17(3H,s,H-30),0.98(3H,s,H-29),0.94(3H,s,H-27),0.91(3H,s,H-26),0.80(3H,s,H-25),0.70(3H,s,H-24);13C NMR(150 MHz,CD3OD)δ:39.9(C-1),26.7(C-2),82.4(C-3),44.1(C-4),48.3(C-5),18.1(C-6),33.5(C-7),40.8(C-8),49.7(C-9),37.8(C-10),24.2(C-11),123.9(C-12),145.1(C-13),43.2(C-14),29.1(C-15),24.7(C-16),48.2(C-17),42.7(C-18),47.4(C-19),31.7(C-20),35.0(C-21),33.3(C-22),64.7(C-23),13.9(C-24),16.7(C-25),18.0(C-26),26.5(C-27),178.2(C-28),33.7(C-29),24.2(C-30),104.5(C-1′),76.8(C-2′),74.1(C-3′),70.3(C-4′),65.0(C-5′),102.0(C-1″),72.1(C-2″),72.2(C-3″),74.0(C-4″),69.4(C-5″),19.0(C-6″),95.9(C-1?),73.9(C-2?),78.1(C-3?),71.0(C-4?),77.9(C-5?),69.6(C-6?),104.8(C-1″″),75.3(C-2″″),78.3(C-3″″),71.6(C-4″″),78.1(C-5″″),62.9(C-6″″)。以上數(shù)據(jù)與文獻[12]報道一致,鑒定為川續(xù)斷皂苷B。
化合物5白色粉末(甲醇);化學式為C65H106O32,ESI-MS:m/z1073 [M-2Glc-H]-;1H NMR(600 MHz,CD3OD)δ:5.35(1H,d,J=8.2 Hz,H-1″″′),5.25(1H,br s,H-12),5.16(1H,s,H-1′),4.94(1H,overlapped,H-1″″″),4.64(1H,s,H-l″ ),4.54(1H,d,J=7.8 Hz,H-l″″),4.41(1H,d,J=7.9 Hz,H-l?),3.38(1H,m,H-3),1.26(3H,d,J=6.2 Hz,H-6″),1.17(3H,s,H-25),0.98(3H,s,H-24),0.94(3H,s,H-27),0.92(3H,s,H-26),0.80(3H,s,H-30),0.70(3H,s,H-29);13C NMR(150 MHz,CD3OD)δ:39.9(C-1),26.8(C-2),82.5(C-3),44.1(C-4),48.3(C-5),18.3(C-6),33.5(C-7),40.8(C-8),48.2(C-9),37.8(C-10),24.2(C-11),123.9(C-12),145.1(C-13),43.2(C-14),29.1(C-15),24.7(C-16),48.2(C-17),42.7(C-18),47.4(C-19),31.7(C-20),35.0(C-21),33.4(C-22),64.7(C-23),13.9(C-24),16.7(C-25),18.0(C-26),26.5(C-27),178.2(C-28),33.7(C-29),24.2(C-30),104.7(C-1′),76.2(C-2′),74.3(C-3′),70.2(C-4′),66.0(C-5′),101.8(C-1″),71.7(C-2″),83.1(C-3″),72.7(C-4″),70.0(C-5″),19.0(C-6″),105.8(C-1?),75.3(C-2?),76.8(C-3?),80.2(C-4?),76.5(C-5?),61.7(C-6?),104.8(C-1″″),75.0(C-2″″),78.3(C-3″″),71.5(C-4″″),78.1(C-5″″),62.7(C-6″″),95.9(C-1″″′),74.0(C-2″″′),78.0(C-3″″′),71.0(C-4″″′),78.0(C-5″″′),69.6(C-6″″′),105.2(C-1″″″),75.2(C-2″″″),78.3(C-3″″″),71.(C-4″″″),78.2(C-5″″″),62.5(C-6″″″)。以上數(shù)據(jù)與文獻[13]報道一致,鑒定為灰氈毛忍冬皂苷B。
化合物6白色粉末(甲醇);化學式為C59H96O26,ESI-MS:m/z749 [M-2Glc-Rha-H]-;1H NMR(600 MHz,CD3OD)δ:5.33(1H,d,J=7.8 Hz,H-1?),5.25(1H,t,J=3.4 Hz,H-12),5.16(1H,d,J=1.2 Hz,H-1″),4.84(1H,d,J=1.2 Hz,H-1″″),4.54(1H,d,J=5.4 Hz,H-l″″′),4.40(1H,d,J=7.8 Hz,H-l′),3.23(1H,dd,J=9.0,8.4 Hz,H-3),1.27(3H,d,J=6.0 Hz,H-6″),1.24(3H,d,J=6.0 Hz,H-6″″′),1.17(3H,s,H-30),0.98(3H,s,H-29),0.94(3H,s,H-27),0.91(3H,s,H-26),0.80(3H,s,H-25),0.70(3H,s,H-2);13C NMR(150 MHz,CD3OD)δ:39.8(C-1),26.7(C-2),82.4(C-3),43.1(C-4),48.2(C-5),18.0(C-6),33.4(C-7),40.8(C-8),48.3(C-9),37.8(C-10),24.7(C-11),123.9(C-12),145.1(C-13),42.7(C-14),29.1(C-15),24.2(C-16),47.4(C-17),41.7(C-18),44.1(C-19),31.7(C-20),35.0(C-21),33.4(C-22),64.7(C-23),13.9(C-24),16.7(C-25),18.0(C-26),26.5(C-27),178.3(C-28),33.6(C-29),24.3(C-30),104.4(C-1′),76.7(C-2′),74.1(C-3′),69.4(C-4′),65.1(C-5′),102.0(C-1″),72.2(C-2″),72.2(C-3″),74.0(C-4″),70.3(C-5″),18.1(C-6″),95.9(C-1?),73.9(C-2?),79.6(C-3?),71.0(C-4?),78.2(C-5?),69.5(C-6?),104.6(C-1″″),75.4(C-2″″),76.9(C-3″″),78.3(C-4″″),77.0(C-5″″),62.0(C-6″″),103.1(C-1″″′),72.3(C-2″″′),72.6(C-3″″′),73.9(C-4″″′),70.8(C-5″″′),19.0(C-6″″′)。以上數(shù)據(jù)與文獻[14]報道一致,鑒定常春藤皂苷C。
化合物7白色粉末(吡啶);化學式為C41H64O13,ESI-MS:m/z763 [M-H]-;1H NMR(600 MHz,Pyr)δ:5.37(1H,overlapped,H-1″),5.25(1H,brs,H-l2),5.03(1H,overlapped,H-1′),3.30(1H,d,J=10.8 Hz,H-3),1.33(3H,s,H-27),1.32(3H,s,H-23),1.01(3H,s,H-25),0.99(6H,s,H-24,H-29),0.97(3H,s,H-30),0.79(3H,s,H-26);13C NMR(150 MHz,Pyr)δ:39.0(C-1),26.7(C-2),89.6(C-3),40.0(C-4),56.1(C-5),20.0(C-6),33.8(C-7),40.2(C-8),48.4(C-9),37.4(C-10),24.2(C-11),123.0(C-12),145.3(C-13),42.6(C-14),28.5(C-15),24.1(C-16),47.1(C-17) 42.4(C-18),46.9(C-19),31.4(C-20),34.7(C-21),33.6(C-22),28.8(C-23),17.8(C-24),17.4(C-25),18.9(C-26),27.0(C-27),180.9(C-28),33.7(C-29),24.2(C-30),107.2(C-1′),75.1(C-2′),86.7(C-3′),72.0(C-4′),80.3(C-5′),180.7(C-6′),106.6(C-1″),75.7(C-2″),78.6(C-3″),71.4(C-4″),67.9(C-5″)。以上數(shù)據(jù)與文獻[15]報道一致,鑒定為地膚子皂苷Ic。
化合物8白色粉末(甲醇);化學式為C10H10O4,EI-MS:m/z194 [M]+;1H NMR(600 MHz,CD3OD)δ:7.59(1H,d,J=16.2 Hz,H-3),7.17(1H,d,J=1.8 Hz,H-5),7.06(1H,dd,J=8.4,1.8 Hz,H-9),6.81(1H,d,J=7.8 Hz,H-8),6.31(1H,d,J=15.6 Hz,H-2),3.89(3H,s,H-10);13C NMR(150 MHz,CD3OD)δ:171.1(C-1),116.6(C-2),147.1(C-3),127.9(C-4),124.1(C-5),116.0(C-6),150.6(C-7),149.5(C-8),111.7(C-9),56.5(C-10)。以上數(shù)據(jù)與文獻[16]報道一致,鑒定為阿魏酸。
化合物9白色粉末(DMSO);化學式為C13H18O7,EI-MS:m/z286 [M]+;1H NMR(600 MHz,DMSO-d6)δ:7.36(1H,d,J=7.2 Hz,H-6),7.20(1H,m,H-4),7.09(1H,d,J=7.9 Hz,H-3),7.00(1H,m,H-5),5.36(1H,d,J=4.2 Hz,H-1′);13C NMR(150 MHz,DMSO-d6)δ:131.5(C-1),154.7(C-2),114.7(C-3),127.7(C-4),121.7(C-5),127.1(C-6),58.2(C-7),101.4(C-1′),73.4(C-2′),77.1(C-3′),69.7(C-4′),76.5(C-5′),60.8(C-6′)。以上數(shù)據(jù)與文獻[17]報道一致,鑒定為水楊苷。
化合物10白色粉末(甲醇);化學式為C16H18O9,EI-MS:m/z354 [M]+;1H NMR(600 MHz,CD3OD)δ:7.56(1H,d,J=16.2 Hz,H-7′),7.05(1H,d,J=1.8 Hz,H-2′),6.95(1H,dd,J=8.4,1.8 Hz,H-6′),6.78(1H,d,J=8.4 Hz,H-5′),6.26(1H,d,J=16.2 Hz,H-8′),5.33(1H,td,J=9.0,4.4 Hz,H-5),4.16(1H,m,H-3),3.73(1H,dd,J=8.4,3.0 Hz,H-4),2.21(2H,ddd,J=17.0,13.6,2.5 Hz,H-2),2.06(2H,ddd,J=14.1,9.0,6.7Hz,H-6);13C NMR(150 MHz,CD3OD)δ:76.2(C-1),38.3(C-2),71.4(C-3),73.5(C-4),72.1(C-5),38.9(C-6),177.1(C-7),127.9(C-1′),115.3(C-2′),146.9(C-3′),149.7(C-4′),116.6(C-5′),123.1(C-6′),147.2(C-7′),115.3(C-8′),168.8(C-9′)。以上數(shù)據(jù)與文獻[18]報道一致,鑒定為綠原酸。
化合物11黃色粉末(甲醇);化學式為C27H30O16,EI-MS:m/z610 [M]+;1H NMR(500 MHz,CD3OD)δ:7.66(1H,t,J=3.5 Hz,H-2′),7.62(1H,dd,J=10.2,3.0 Hz,H-6′),6.86(1H,d,J=10.2 Hz,H-5′),6.39(1H,d,J=2.4 Hz,H-8),6.20(1H,d,J=2.4 Hz,H-6),5.10(1H,d,J=9.6 Hz,H-1″),4.51(1H,d,J=1.8 Hz,H-1?),1.11(3H,d,J=7.8 Hz,H-6?);13C NMR(125 MHz,CD3OD)δ:158.5(C-2),135.6(C-3),179.4(C-4),163.0(C-5),99.9(C-6),166.0(C-7),94.8(C-8),159.3(C-9),105.6(C-10),123.1(C-1′),116.0(C-2′),149.8(C-3′),145.8(C-4′),117.7(C-5′),123.5(C-6′),104.7(C-1″),75.7(C-2″),77.2(C-3″),72.2(C-4″),78.2(C-5″),68.5(C-6″),102.4(C-1?),72.1(C-2?),71.4(C-3?),73.9(C-4?),69.7(C-5?),17.9(C-6?)。以上數(shù)據(jù)與文獻[19]報道一致,鑒定為蘆丁。
化合物12白色粉末(DMSO);化學式為C10H13N5O4,EI-MS:m/z267 [M]+;1H NMR(600 MHz,DMSO-d6)δ:8.35(1H,s,H-8),8.13(1H,s,H-2),5.87(1H,d,J=6.0 Hz,H-1′),5.22(1H,d,J=4.2 Hz,OH-3′),4.60(1H,dd,J=11.4,6.0 Hz,H-2′),4.13(1H,dd,J=7.8,4.8 Hz,H-3′),3.96(1H,q,J=3.6 Hz,H-4′),3.59(2H,m,H-5′);13C NMR(150 MHz,DMSO-d6)δ:152.4(C-2),149.1(C-4),119.4(C-5),156.2(C-6),140.0(C-8),87.9(C-1′),73.4(C-2′),70.7(C-3′),85.9(C-4′),61.7(C-5′)。以上數(shù)據(jù)與文獻[20]報道一致,鑒定為β-adenosine。
化合物13白色針狀結晶;與β-sitosterol標準品對照,經薄層色譜(TLC)檢測,其Rf值在三種不同溶劑體系中一致且顯色相同,故確定為β-谷甾醇。
化合物14白色粉末(氯仿);化學式為C16H32O2,EI-MS:m/z256 [M]+;1H NMR(600 MHz,CDCl3)δ:2.35(2H,t,J=7.8 Hz,H-2),1.63(2H,dt,J=15.0,7.2 Hz,H-3),0.88(3H,t,J=4.8 Hz,H-16);13C NMR(150 MHz,CDCl3)δ:179.5(C-1),34.1(C-2),32.2(C-3),29.9~29.3(C-4~C-13),24.9(C-14),22.9(C-15),14.4(C-16)。以上數(shù)據(jù)與文獻[21]報道一致,鑒定為棕櫚酸。
對刺通草分離得到的化合物1~6和化合物8~11,共10個化合物進行了人腫瘤細胞株SMMC-7721、Hela、MCF-7的體外細胞毒活性研究。由表1可知,化合物1和3對所有人腫瘤細胞株均顯示出明顯的細胞毒活性。化合物1對人腫瘤細胞株SMMC-7721、Hela、MCF-7的抑制率分別為100%、99.64%、99.71%;化合物3對人腫瘤細胞株SMMC-7721、Hela、MCF-7的抑制率分別為87.47%、96.68%、93.46%。進一步的評估結果顯示(表2),化合物1對人腫瘤細胞株SMMC-7721、Hela和MCF-7的細胞毒活性(IC50值)分別為10.37±0.19、28.57±0.93和4.92±0.49 μM;化合物3對人腫瘤細胞株SMMC-7721、Hela和MCF-7的細胞毒性(IC50值)分別為17.46±0.19、51.80±4.38和6.75±0.18 μM。
表1 刺通草單體化合物對SMMC-7721、Hela、MCF-7細胞株的細胞毒活性Table 1 Cytotoxicity of compounds on SMMC-7721,Hela and MCF-7 cell =2)
表2 化合物1和化合物3的細胞毒活性Table 2 Cytotoxicity of compound 1 and compound =2)
本研究從刺通草中分離得到14個化合物,其中化合物2~14為首次從刺通草中分離得到。對人腫瘤細胞株SMMC-7721、Hela、MCF-7的細胞毒活性篩選結果顯示,化合物1和3對3種人腫瘤細胞株均顯示出較為明顯的細胞毒活性,且化合物1對人腫瘤細胞株SMMC-7721、Hela和MCF-7的細胞毒活性(其對三種人腫瘤細胞株的IC50值分別為10.37±0.19、28.57±0.93和4.92±0.49 μM),均優(yōu)于陽性藥物順鉑DDP(其對三種人腫瘤細胞株的IC50值分別為38.79±2.97、42.59±4.23和39.86±2.10 μM);而化合物3對人腫瘤細胞株SMMC-7721和MCF-7的細胞毒活性(其對人腫瘤細胞株SMMC-7721和MCF-7的IC50值分別為17.46±0.19和6.75±0.18 μM)也優(yōu)于陽性藥物順鉑DDP。其中化合物1對宮頸癌細胞Hela的細胞毒活性為首次報道,具有一定的抗腫瘤藥物開發(fā)潛力。本研究通過對刺通草化學成分和腫瘤細胞毒活性的研究,進一步明確了刺通草的抗腫瘤活性藥效物質基礎,為刺通草在抗腫瘤方面的開發(fā)利用提供了一定的理論依據(jù)。