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刺齿凤尾蕨化学成分及其体外抗肿瘤活性研究

2017-11-17王佳娜张艳宋丽艳彭玉勃李文静

中国中药杂志 2017年21期

王佳娜 张艳 宋丽艳 彭玉勃 李文静

[摘要]乙醇提取刺齿凤尾蕨药材,提取物依次经过有机溶剂萃取,聚酰胺柱色谱、葡聚糖凝胶柱色谱和制备型HPLC色谱分离得到10个对映贝壳杉烷型二萜类化合物。采用核磁共振(NMR)和质谱(ESIMS)技术鉴定获得的化合物分别为geopyxin B(1), geopyxin E(2), ent11αhydroxy18acetoxykaur16ene(3), ent14βhydroxy18acetoxykaur16ene(4), neolaxiflorin L(5), ent3β,19dihydroxykaur16ene(6), ent3βhydroxykaur16ene(7),7β,17dihydroxy16αentkauran19oic acid 19OβDglucopyranoside ester(8),crotonkinin C(9)和crotonkinin C(10)。化合物1~10均为首次从刺齿凤尾蕨中获得。体外活性研究表明,化合物1和2对Bel7402细胞具有抑制作用,IC50分别为750,1060 μmol·L-1;化合物1和2对HepG2细胞具有抑制作用,IC50分别为668,1180 μmol·L-1。

[关键词]刺齿凤尾蕨; 对映贝壳杉烷二萜; 体外抗肿瘤活性

[Abstract]The dried whole plant of Pteris dispar were milled and extracted with 95% EtOH The resulting dried extract was isolated by kinds of chromatographic column, including polyamide, Sephadex LH20, preparative HPLC As a result, ten diterpenes were isolated from the plant By analyzing of ESIMS and NMR spectroscopic data, the structures were established as geopyxin B(1), geopyxin E(2), ent11αhydroxy18acetoxykaur16ene(3), ent14βhydroxy18acetoxykaur16ene(4), neolaxiflorin L(5), ent3β,19dihydroxykaur16ene(6), ent3βhydroxykaur16ene(7), 7β,17dihydroxy16αentkauran19oic acid 19OβDglucopyranoside ester(8), crotonkinin C(9)and crotonkinin C(10) Compounds 110 were obtained from P. dispar for the first time Compounds 1 and 2 showed moderate activities against Bel7402 with IC50 values of 750 and 1060 μmol·L-1, and against HepG2 with IC50 values of 668,1180 μmol·L-1, respectively.

[Key words]Pteris dispar; entkauranetypediterpene; in vitro antitumor activity

鳳尾蕨科Pteridaceae凤尾蕨属Pteris植物在全球有300多种,其中20多种为药用植物,民间使用广泛,大多具有清热、解毒、消肿等功效[1],具有重要的药用价值。近些年国内外学者对该属植物几个种进行了化学成分和生物活性研究:化学成分包括对映贝壳杉烷二萜类、倍半萜类、黄酮类等化学成分,其中对映贝壳杉烷二萜类化学成分报道较多也是该属植物特征性成分[25]。生物活性研究表明,对映贝壳杉烷型二萜类化合物具有显著的抗肿瘤活性,如从凤尾蕨属植物半边旗P. semipinnata L中分离得到的该类型二萜类化合物11βhydroxy15oxoentkaur16en19oic acid和7β,9dihydroxy15oxoentkaur16en19,6βolide具有广谱抗肿瘤作用[6]。

刺齿凤尾蕨系凤尾蕨科植物刺齿凤尾蕨P. dispar Kunze的干燥全草,具有清热解毒、止血祛痰的功效,民间用于治疗肠炎、痢疾、疮毒等症[7]。龚先玲等发现刺齿凤尾蕨的提取物对多种人癌细胞具有明显的抑制作用[8]。Murakami T等从该种植物中获得5个二萜类化合物[910],其中二萜化合物11βhydroxy15oxoentkaur16en19oic aci对多种肿瘤细胞具有抑制活性[6,1112]。本文对刺齿凤尾蕨中对映贝壳杉烷型二萜类化学成分及其体外抗肝癌活性做了系统研究,分离并鉴定了10个对映贝壳杉烷型二萜类化合物,其中2个化合物对Bel7402和HepG2 2种人源肝癌细胞具有较强的抑制作用。

1材料

Agilent 1100制备型高效液相色谱仪(安捷伦科技公司,美国),YMC C18 制备型色谱柱(20 mm×250 mm,5 μm,YMC公司,日本);Varian VNS400核磁共振仪(Varian公司,美国),TMS为内标;Agilent 1200 高效液相色谱仪(安捷伦科技公司,美国);聚酰胺树脂(60~90目,浙江台州市路桥四甲生化塑料厂,中国); Sephadex LH20(25~100 μm,Pharmacia Biotek公司);乙腈、甲醇(色谱纯,Fisher、TEDIA公司,美国);MTT(sigama公司,美国);人源肝癌细胞Bel7402和HepG2购自中国医学科学院药物研究所;Thermo热电 FC酶标仪(热电公司,美国)。endprint

药材于2015年5月采集于云南省西双版纳地区,经黑龙江中医药大学陈效忠副教授鉴定为刺齿凤尾蕨P. dispar的全草。药材标本保存于黑龙江中医药大学佳木斯学院标本馆(标本号IDg20150825)。

2试验方法

21提取与分离以95%乙醇回流提取刺齿凤尾蕨药材(85 kg),提取2次,每次1 h。减压回收乙醇,浸膏(20 kg)分散于蒸馏水中,以石油醚、乙酸乙酯、正丁醇分别萃取,得到相应的4个萃取部位。乙酸乙酯萃取物过酰胺树脂,分别以水,30%乙醇、60%乙醇、95%乙醇洗脱,得到4个洗脱部位。30%乙醇洗脱物(500g)过sephadex LH20色谱柱(甲醇为洗脱剂),获得30个流分,即S1~S30。S15(15 g)过sephadex LH20色谱柱(洗脱剂为甲醇水,50∶50)获得化合物5(65 mg)。制备型HPLC(甲醇水,40∶60,流速 50 mL·min-1)对S19进行分离,得到化合物1(180 mg, tR=180 min)和2(120 mg,tR=151 min)。制备型HPLC(甲醇水,40∶60,流速 50 mL·min-1)对S21进行分离,得到化合物3(305 mg,tR=226 min),6(222 mg,tR=182 min)和7(330 mg,tR=153 min)。制备型HPLC(甲醇水,45∶50,流速50 mL·min-1)对S25进行分离,得到化合物4(120 mg,tR=220 min),9(80 mg,tR=280 min)和10(80 mg,tR=300 min)。正丁醇萃取物(65 g)过Sephadex LH20色谱柱(甲醇为洗脱剂),获得20个流分,即Z1Z20。制备型HPLC(甲醇水,45∶55,流速50 mL·min-1)对Z7进行分离,得到化合物8(250 mg,tR=250 min)。

22体外抗肿瘤活性测试[13] 取2种人源肝癌肿瘤细胞(Bel7402和HepG2)分别加入96孔细胞培养板中,于37℃,5%CO2的细胞培养箱中培养3 h。将待测化合物依次配置成032,16,80,400,2000 μmol·L-1不同浓度溶液,将溶液加入细胞培养板内继续培养。培养96 h后,弃去培养液。将01 mL PBS和10 μL MTT染液加入培养板,最后在每孔加入100 μL Formanzan溶解液。用酶标仪测定500 nm处的吸收度A,采用SPSS180软件计算IC50。

3结构鉴定

化合物1白色粉末。ESIMS m/z 333 [M+H]+,相对分子质量为332,分子式为C20H28O4。 1HNMR(CDCl3,400 MHz)δ:187(1H,m,H1a),094(1H,m,H1b),170(1H,m,H2a),146(1H,m,H2b),217(1H,m,H3a),111(1H,m,H3b),204(1H,m,H5),203(1H,m,H6a),193(1H,m,H6b),392(1H,dd,J=35,20 Hz,H7),183(1H,d,J=80 Hz,H9),185(1H,m,H11a),147(1H,m,H11b),191(1H,m,H12a),170(1H,m,H12b),307(1H,br d,J=24 Hz,H13),230(1H,d,J=120 Hz,H14a),147(1H,m,H14b),600(1H,s,H17a),532(1H,s,H17b),127(3H,s,H18),103(3H,s,H20); 13CNMR(CDCl3,100 MHz)δ:399(C1),184(C2),375(C3),433(C4),466(C5),274(C6),724(C7),533(C8),464(C9),401(C10),189(C11),328(C12),381(C13),349(C14),2145(C15),1492(C16),1162(C17),288(C18),1844(C19),158(C20)。以上數据与文献[14]对比,故鉴定化合物为 geopyxin B。

化合物2白色粉末。ESIMS m/z 365 [M+H]+,相对分子质量为364,分子式为C20H28O6。1HNMR(CDCl3,400 MHz)δ:307(1H,d,J=90 Hz,H1),381(1H,m,H2),235(1H,dd,J=124,48 Hz,H3a),116(1H,t,J=124 Hz,H3b),202(1H,m,H5),196(1H,m,H6a),198(1H,m,H6b),381(1H,br s,H7),203(1H,d,J=78 Hz,H9),297(1H,dd,J=157,52 Hz,H11a),146(1H,m,H11b),198(1H,m,H12a),160(1H,br d,J=146 Hz,H12b),303(1H,br s,H13),220(1H,d,J=117 Hz,H14a),147(1H,m,H14b),593(1H,s,H17a),528(1H,s,H17b),121(3H,s,H18),109(3H,s,H20); 13CNMR(CDCl3,100 MHz)δ:865(C1),689(C2),435(C3),435(C4),446(C5),270(C6),724(C7),534(C8),472(C9),451(C10),206(C11),329(C12),383(C13),355(C14),2151(C15),1496(C16),1159(C17),286(C18),1805(C19),129(C20)。以上数据与文献[14]对比,故鉴定化合物为 geopyxin E。

化合物3白色粉末。ESIMS m/z 347 [M+H]+,相对分子质量为346,分子式为C22H34O3。 1HNMR(CDCl3,400 MHz)δ:193(1H,dd,J=110,25 Hz,H1a),108(1H,m,H1b),157(1H,m,H2a),143(1H,m,H2a),153(1H,m,H3a),139(1H,m,H3b),120(1H,m,H5),152(1H,m,H6a),136(1H,m,H6b),195(1H,m,H7a),148(1H,m,H7b),146(1H,m,H9),388(1H,dd,J=110,55 Hz,H11),223(1H,m,H12a),199(1H,m,H12b),273(1H,br s,H13),190(1H,m,H14a),115(1H,m,H14b),251(1H,d,J=170 Hz,H15a),212(1H,m,H15b),506(1H,s,H17a),489(1H,s,H17b),390(1H,d,J=110 Hz,H18a),366(1H,d,J=110 Hz,H18b),085(3H,s,H19),097(3H,s,H20),209(3H,s,18OAc); 13CNMR(CDCl3,100 MHz)δ:393(C1),178(C2),358(C3),366(C4),499(C5),200(C6),433(C7),429(C8),651(C9),379(C10),671(C11),407(C12),422(C13),395(C14),489(C15),1562(C16),1054(C17),729(C18),177(C19),178(C20),210(18OAc),1715(18OAc)。以上数据与文献[15]对比,故鉴定化合物为ent11αhydroxy18acetoxykaur16ene。endprint

化合物4白色粉末。ESIMS m/z 347 [M+H]+,相对分子质量为346,分子式为C22H34O3。1HNMR(CDCl3,400 MHz)δ:182(1H,m,H1a),079(1H,m,H1b),162(1H,m,H2a),160(1H,m,H2a),142(1H,m,H3a),139(1H,m,H3b),113(1H,d,J=120 Hz,H5),148(1H,m,H6a),139(1H,m,H6b),219(1H,m,H7a),116(1H,m,H7b),137(1H,m,H9),158(1H,m,H11a),133(1H,m,H11b),184(1H,m,H12a),166(1H,m,H12b),263(1H,br s,H13),417(1H,br s,H14),232(1H,d,J=166 Hz,H15a),203(1H,dt,J=166,15 Hz,H15b),496(1H,s,H17a),495(1H,s,H17b),388(1H,d,J=105 Hz,H18a),367(1H,d,J=105 Hz,H18b),086(3H,s,H19),111(3H,s,H20),208(3H,s,18OAc); 13CNMR(CDCl3,100 MHz)δ:399(C1),178(C2),357(C3),365(C4),505(C5),199(C6),320(C7),494(C8),589(C9),393(C10),180(C11),332(C12),519(C13),763(C14),447(C15),1528(C16),1069(C17),732(C18),176(C19),186(C20),1714(18OAc),211(18OAc)。以上數据与文献[15]对比,故鉴定化合物为ent14βhydroxy18acetoxykaur16ene。

化合物5白色粉末。ESIMS m/z 347 [M+H]+,相对分子质量为346,分子式为C20H26O5。 1HNMR(CDCl3,400 MHz)δ:268(1H,ddd,J=150,110,67 Hz,H2a),233(1H,ddd,J=150,87,44 Hz,H2b),184(1H,m,H3a),158(1H,m,H3b),229(1H,d,J=82 Hz,H5),422(1H,d,J=82 Hz,H6),225(1H,dd,J=116,50 Hz,H9),200(1H,m,H11a),132(1H,m,H11b),209(1H,m,H12a),133(1H,m,H12b),288(1H,dd,J=90,38 Hz,H13),247(1H,dd,J=125,43 Hz,H14a),243(1H,d,J=125 Hz,H14b),604(1H,br s,H17a),536(1H,br s,H17b),125(3H,s,H18),090(3H,s,H19),458(1H,d,J=102 Hz,H20a),417(1H,d,J=102 Hz,H20b); 13CNMR(CDCl3,100 MHz)δ:2128(C1),362(C2),391(C3),333(C4),618(C5),740(C6),969(C7),603(C8),479(C9),493(C10),192(C11),301(C12),349(C13),237(C14),2091(C15),1536(C16),1183(C17),312(C18),235(C19),652(C20)。以上数据与文献[16]对比,故鉴定化合物为 neolaxiflorin L。

化合物6白色粉末。ESIMS m/z 305 [M+H]+,相对分子质量为304,分子式为C20H32O2。 1HNMR(CDCl3,400 MHz)δ:188(1H,m,H1a),092(1H,m,H1b),186(1H,m,H2a),172(1H,m,H2b),343(1H,m,H3),089(1H,m,H5),177(1H,m,H6a),131(1H,m,H6b),152(1H,m,H7a),149(1H,m,H7b),105(1H,m,H9),165(1H,m,H11a),154(1H,m,H11b),193(1H,m,H12a),111(1H,m,H12b),266(1H,m,H13),164(1H,m,H14a),150(1H,m,H14b),207(1H,m,H15a),206(1H,m,H15b),482(1H,m,H17a),475(1H,m,H17b),124(3H,s,H18),422(1H,d,J=112 Hz,H19a),333(1H,d,J=112 Hz,H19b),099(3H,s,H20); 13CNMR(CDCl3,100 MHz)δ:385(C1),279(C2),811(C3),430(C4),559(C5),202(C6),415(C7),441(C8),560(C9),388(C10),186(C11),397(C12),440(C13),332(C14),491(C15),1557(C16),1033(C17),229(C18),644(C19),183(C20)。以上数据与文献[17]对比,故鉴定化合物为ent3β,19dihydroxykaur16ene。

化合物7白色粉末。ESIMS m/z 289 [M+H]+,相对分子质量为288,分子式为C20H33O。 1HNMR(CDCl3,400 MHz)δ:187(1H,ddd,J=132,37,34 Hz,H1a),091(1H,ddd,J=132,124,52 Hz,H1b),165(1H,m,H2a),162(1H,m,H2b),320(1H,m,H3),077(1H,m,H5),157(1H,m,H6a),142(1H,m,H6b),153(1H,m,H7a),149(1H,m,H7b),105(1H,m,H9),163(1H,m,H11a),154(1H,m,H11b),199(1H,m,H12a),113(1H,m,H12b),266(1H,m,H13),163(1H,m,H14a),150(1H,m,H14b),207(1H,m,H15a),206(1H,m,H15b),482(1H,m,H17a),475(1H,m,H17b),099(3H,s,H18),080(3H,s,H19),103(3H,s,H20); 13CNMR(CDCl3,100 MHz)δ:388(C1),275(C2),793(C3),390(C4),553(C5),202(C6),413(C7),442(C8),560(C9),392(C10),186(C11),399(C12),441(C13),333(C14),492(C15),1559(C16),1031(C17),285(C18),157(C19),177(C20)。以上数据与文献[17]对比,故鉴定化合物为ent3βhydroxykaur16ene。endprint

化合物8白色粉末。ESIMS m/z 499 [M+H]+,相对分子质量为498,分子式为C26H42O9。1HNMR(CDCl3,400 MHz)δ:189(1H,m,H1a),095(1H,m,H1b),196(1H,m,H2a),147(1H,m,H2b),223(1H,m,H3a),114(1H,m,H3b),180(1H,d,J=130 Hz,H5),219(1H,dd,J=145,130 Hz,H6a),198(1H,m,H6b),352(1H,br s,H7),145(1H,m,H9),164(1H,m,H11a),158(1H,m,H11b),165(1H,m,H12a),145(1H,m,H12b),212(1H,m,H13),181(1H,d,J=115 Hz,H14a),109(1H,m,H14b),172(1H,m,H15a),113(1H,m,H15b),196(1H,m,H16),337(1H,m,H17),124(3H,s,H18),100(3H,s,H20),544(1H,d,J=80 Hz,H1′19OGlc),339(1H,m,H2′19OGlc),347(1H,m,H3′19OGlc),340(1H,m,H4′19OGlc),340(1H,m,H5′19OGlc),388(1H,d,J=115 Hz,H6a′19OGlc),373(1H,dd,J=115,40 Hz,H6b′19OGlc);13CNMR(CDCl3,100 MHz)δ:419(C1),204(C2),392(C3),448(C4),496(C5),309(C6),788(C7),499(C8),508(C9),407(C10),196(C11),331(C12),397(C13),374(C14),427(C15),448(C16),679(C17),289(C18),1788(C19),164(C20),958(1′19OGlc),743(2′19OGlc),788(3′19OGlc),712(4′19OGlc),787(5′19OGlc),626(6′19OGlc)。以上數据与文献[18]对比,故鉴定化合物为7β,17dihydroxy16αentkauran19oic acid 19OβDglucopyranoside ester。

化合物9白色粉末。ESIMS m/z 375 [M+H]+,相对分子质量为374,分子式为C22H30O5。1HNMR(CDCl3,500 MHz)δ:199(1H,m,H1a),099(1H,m,H1b),201(1H,m,H2a),149(1H,m,H2b),176(1H,m,H3),177(1H,m,H5),159(1H,m,H6a),099(1H,m,H6b),218(1H,br d,J=110 Hz,H7a),159(1H,m,H7b),137(1H,br s,H9),517(1H,d,J=54 Hz,H11),188(1H,m,H12a),166(1H,m,H12b),299(1H,m,H13),188(1H,m,H14),660(1H,s,H15),975(1H,s,H17),118(3H,s,H19),108(3H,s,H20),190(3H,s,18OAc); 13CNMR(CDCl3,100 MHz)δ:386(C1),217(C2),368(C3),473(C4),494(C5),175(C6),422(C7),495(C8),554(C9),383(C10),681(C11),371(C12),361(C13),344(C14),1621(C15),1507(C16),1892(C17),1827(C18),162(C19),180(C20),1694(C21),214(18OAc)。以上数据与文献[19]对比,故鉴定化合物为 crotonkinin C。

化合物10白色粉末。ESIMS m/z 419 [M+H]+,相对分子质量为418,分子式为C24H34O6。1HNMR(CDCl3,500 MHz)δ:198(1H,m,H1a),086(1H,m,H1b),148(1H,m,H2a),136(1H,m,H2b),136(1H,m,H3),115(1H,d,J=107 Hz,H5),165(1H,m,H6a),148(1H,m,H6b),171(1H,m,H7),125(1H,br s,H9),517(1H,d,J=37 Hz,H11),194(1H,m,H12),289(1H,m,H13),217(1H,d,J=109 Hz,H14a),165(1H,m,H14b),664(1H,s,H15),387(1H,d,J=110 Hz,H18a),363(1H,d,J=110 Hz,H18b),082(3H,s,H19),108(3H,s,H20),207(3H,s,11OAc),193(3H,s,18OAc); 13CNMR(CDCl3,100 MHz)δ:390(C1),185(C2),356(C3),365(C4),493(C5),175(C6),373(C7),491(C8),550(C9),388(C10),686(C11),344(C12),385(C13),423(C14),1569(C15),1396(C16),1690(C17),726(C18),174(C19),181(C20),1713(11OAc),210(11OAc),1696(18OAc),214(18OAc)以上数据与文献[19]对比,故鉴定化合物为 crotonkinin D。

4结果与讨论

本文对刺齿凤尾蕨二萜类化学成分进行了研究,获得10个对映贝壳杉烷二萜类化合物,这些二萜化合物均首次从该植物中获取。2个化合物具有较强的抑制2种人源肝癌肿瘤细胞活性,见表1。在此基础上发现抗肿瘤先导化合物,为创制新型二萜类抗肿瘤药物奠定基础。endprint

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[責任编辑丁广治]endprint