王佳娜 張艷 宋麗艷 彭玉勃 李文靜
[摘要]乙醇提取刺齒鳳尾蕨藥材,提取物依次經(jīng)過有機溶劑萃取,聚酰胺柱色譜、葡聚糖凝膠柱色譜和制備型HPLC色譜分離得到10個對映貝殼杉烷型二萜類化合物。采用核磁共振(NMR)和質(zhì)譜(ESIMS)技術(shù)鑒定獲得的化合物分別為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)?;衔?~10均為首次從刺齒鳳尾蕨中獲得。體外活性研究表明,化合物1和2對Bel7402細胞具有抑制作用,IC50分別為750,1060 μmol·L-1;化合物1和2對HepG2細胞具有抑制作用,IC50分別為668,1180 μmol·L-1。
[關(guān)鍵詞]刺齒鳳尾蕨; 對映貝殼杉烷二萜; 體外抗腫瘤活性
[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鳳尾蕨屬Pteris植物在全球有300多種,其中20多種為藥用植物,民間使用廣泛,大多具有清熱、解毒、消腫等功效[1],具有重要的藥用價值。近些年國內(nèi)外學者對該屬植物幾個種進行了化學成分和生物活性研究:化學成分包括對映貝殼杉烷二萜類、倍半萜類、黃酮類等化學成分,其中對映貝殼杉烷二萜類化學成分報道較多也是該屬植物特征性成分[25]。生物活性研究表明,對映貝殼杉烷型二萜類化合物具有顯著的抗腫瘤活性,如從鳳尾蕨屬植物半邊旗P. semipinnata L中分離得到的該類型二萜類化合物11βhydroxy15oxoentkaur16en19oic acid和7β,9dihydroxy15oxoentkaur16en19,6βolide具有廣譜抗腫瘤作用[6]。
刺齒鳳尾蕨系鳳尾蕨科植物刺齒鳳尾蕨P. dispar Kunze的干燥全草,具有清熱解毒、止血祛痰的功效,民間用于治療腸炎、痢疾、瘡毒等癥[7]。龔先玲等發(fā)現(xiàn)刺齒鳳尾蕨的提取物對多種人癌細胞具有明顯的抑制作用[8]。Murakami T等從該種植物中獲得5個二萜類化合物[910],其中二萜化合物11βhydroxy15oxoentkaur16en19oic aci對多種腫瘤細胞具有抑制活性[6,1112]。本文對刺齒鳳尾蕨中對映貝殼杉烷型二萜類化學成分及其體外抗肝癌活性做了系統(tǒng)研究,分離并鑒定了10個對映貝殼杉烷型二萜類化合物,其中2個化合物對Bel7402和HepG2 2種人源肝癌細胞具有較強的抑制作用。
1材料
Agilent 1100制備型高效液相色譜儀(安捷倫科技公司,美國),YMC C18 制備型色譜柱(20 mm×250 mm,5 μm,YMC公司,日本);Varian VNS400核磁共振儀(Varian公司,美國),TMS為內(nèi)標;Agilent 1200 高效液相色譜儀(安捷倫科技公司,美國);聚酰胺樹脂(60~90目,浙江臺州市路橋四甲生化塑料廠,中國); Sephadex LH20(25~100 μm,Pharmacia Biotek公司);乙腈、甲醇(色譜純,F(xiàn)isher、TEDIA公司,美國);MTT(sigama公司,美國);人源肝癌細胞Bel7402和HepG2購自中國醫(yī)學科學院藥物研究所;Thermo熱電 FC酶標儀(熱電公司,美國)。endprint
藥材于2015年5月采集于云南省西雙版納地區(qū),經(jīng)黑龍江中醫(yī)藥大學陳效忠副教授鑒定為刺齒鳳尾蕨P. dispar的全草。藥材標本保存于黑龍江中醫(yī)藥大學佳木斯學院標本館(標本號IDg20150825)。
2試驗方法
21提取與分離以95%乙醇回流提取刺齒鳳尾蕨藥材(85 kg),提取2次,每次1 h。減壓回收乙醇,浸膏(20 kg)分散于蒸餾水中,以石油醚、乙酸乙酯、正丁醇分別萃取,得到相應的4個萃取部位。乙酸乙酯萃取物過酰胺樹脂,分別以水,30%乙醇、60%乙醇、95%乙醇洗脫,得到4個洗脫部位。30%乙醇洗脫物(500g)過sephadex LH20色譜柱(甲醇為洗脫劑),獲得30個流分,即S1~S30。S15(15 g)過sephadex LH20色譜柱(洗脫劑為甲醇水,50∶50)獲得化合物5(65 mg)。制備型HPLC(甲醇水,40∶60,流速 50 mL·min-1)對S19進行分離,得到化合物1(180 mg, tR=180 min)和2(120 mg,tR=151 min)。制備型HPLC(甲醇水,40∶60,流速 50 mL·min-1)對S21進行分離,得到化合物3(305 mg,tR=226 min),6(222 mg,tR=182 min)和7(330 mg,tR=153 min)。制備型HPLC(甲醇水,45∶50,流速50 mL·min-1)對S25進行分離,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)過Sephadex LH20色譜柱(甲醇為洗脫劑),獲得20個流分,即Z1Z20。制備型HPLC(甲醇水,45∶55,流速50 mL·min-1)對Z7進行分離,得到化合物8(250 mg,tR=250 min)。
22體外抗腫瘤活性測試[13] 取2種人源肝癌腫瘤細胞(Bel7402和HepG2)分別加入96孔細胞培養(yǎng)板中,于37℃,5%CO2的細胞培養(yǎng)箱中培養(yǎng)3 h。將待測化合物依次配置成032,16,80,400,2000 μmol·L-1不同濃度溶液,將溶液加入細胞培養(yǎng)板內(nèi)繼續(xù)培養(yǎng)。培養(yǎng)96 h后,棄去培養(yǎng)液。將01 mL PBS和10 μL MTT染液加入培養(yǎng)板,最后在每孔加入100 μL Formanzan溶解液。用酶標儀測定500 nm處的吸收度A,采用SPSS180軟件計算IC50。
3結(jié)構(gòu)鑒定
化合物1白色粉末。ESIMS m/z 333 [M+H]+,相對分子質(zhì)量為332,分子式為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(shù)據(jù)與文獻[14]對比,故鑒定化合物為 geopyxin B。
化合物2白色粉末。ESIMS m/z 365 [M+H]+,相對分子質(zhì)量為364,分子式為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)。以上數(shù)據(jù)與文獻[14]對比,故鑒定化合物為 geopyxin E。
化合物3白色粉末。ESIMS m/z 347 [M+H]+,相對分子質(zhì)量為346,分子式為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)。以上數(shù)據(jù)與文獻[15]對比,故鑒定化合物為ent11αhydroxy18acetoxykaur16ene。endprint
化合物4白色粉末。ESIMS m/z 347 [M+H]+,相對分子質(zhì)量為346,分子式為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(shù)據(jù)與文獻[15]對比,故鑒定化合物為ent14βhydroxy18acetoxykaur16ene。
化合物5白色粉末。ESIMS m/z 347 [M+H]+,相對分子質(zhì)量為346,分子式為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)。以上數(shù)據(jù)與文獻[16]對比,故鑒定化合物為 neolaxiflorin L。
化合物6白色粉末。ESIMS m/z 305 [M+H]+,相對分子質(zhì)量為304,分子式為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)。以上數(shù)據(jù)與文獻[17]對比,故鑒定化合物為ent3β,19dihydroxykaur16ene。
化合物7白色粉末。ESIMS m/z 289 [M+H]+,相對分子質(zhì)量為288,分子式為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)。以上數(shù)據(jù)與文獻[17]對比,故鑒定化合物為ent3βhydroxykaur16ene。endprint
化合物8白色粉末。ESIMS m/z 499 [M+H]+,相對分子質(zhì)量為498,分子式為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(shù)據(jù)與文獻[18]對比,故鑒定化合物為7β,17dihydroxy16αentkauran19oic acid 19OβDglucopyranoside ester。
化合物9白色粉末。ESIMS m/z 375 [M+H]+,相對分子質(zhì)量為374,分子式為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)。以上數(shù)據(jù)與文獻[19]對比,故鑒定化合物為 crotonkinin C。
化合物10白色粉末。ESIMS m/z 419 [M+H]+,相對分子質(zhì)量為418,分子式為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)以上數(shù)據(jù)與文獻[19]對比,故鑒定化合物為 crotonkinin D。
4結(jié)果與討論
本文對刺齒鳳尾蕨二萜類化學成分進行了研究,獲得10個對映貝殼杉烷二萜類化合物,這些二萜化合物均首次從該植物中獲取。2個化合物具有較強的抑制2種人源肝癌腫瘤細胞活性,見表1。在此基礎(chǔ)上發(fā)現(xiàn)抗腫瘤先導化合物,為創(chuàng)制新型二萜類抗腫瘤藥物奠定基礎(chǔ)。endprint
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