張晨澤,閆萌萌,徐 冰,林宏英,閆文強(qiáng),劉 帥,陳 靜,劉永剛,王鵬龍,雷海民
(1.北京中醫(yī)藥大學(xué)中藥學(xué)院,北京 100102;2.西藏藏醫(yī)學(xué)院教務(wù)處,西藏 拉薩 850000)
候選藥物T-VA的質(zhì)譜裂解規(guī)律及其在大鼠體內(nèi)的代謝產(chǎn)物研究
張晨澤1,閆萌萌1,徐 冰1,林宏英1,閆文強(qiáng)1,劉 帥1,
陳 靜2,劉永剛1,王鵬龍1,雷海民1
(1.北京中醫(yī)藥大學(xué)中藥學(xué)院,北京 100102;2.西藏藏醫(yī)學(xué)院教務(wù)處,西藏 拉薩 850000)
采用液相色譜-線性離子阱-靜電場(chǎng)軌道阱高分辨質(zhì)譜(LC/LTQ-Orbitrap MS)技術(shù)研究候選藥物T-VA的裂解規(guī)律及體內(nèi)代謝,建立了大鼠體內(nèi)T-VA及其代謝產(chǎn)物的LC/MSn分析方法,分析討論了各自的主要碎片離子峰、質(zhì)譜特征與結(jié)構(gòu)信息,發(fā)現(xiàn)了血漿中主要代謝物M1。借鑒藥物化學(xué)的方法,合成得到了代謝產(chǎn)物實(shí)體M1-1,經(jīng)1HNMR、13CNMR、HRMS確認(rèn)其結(jié)構(gòu),根據(jù)其色譜、質(zhì)譜特征進(jìn)行驗(yàn)證,結(jié)果表明,合成得到的M1-1即為血漿主要代謝物M1。借助PC12細(xì)胞模型驗(yàn)證了代謝產(chǎn)物M1的神經(jīng)保護(hù)活性,該結(jié)果可為進(jìn)一步研究其生物轉(zhuǎn)化過程與前藥修飾提供重要信息。
液相色譜-線性離子阱-靜電場(chǎng)軌道阱高分辨質(zhì)譜(LC/LTQ-Orbitrap MS);候選藥物T-VA;裂解規(guī)律;代謝產(chǎn)物;化學(xué)合成;神經(jīng)保護(hù)活性
從天然產(chǎn)物中尋找先導(dǎo)化合物是新藥研發(fā)的基本方法之一[1-2]。神經(jīng)系統(tǒng)疾病,如老年癡呆(AD)、帕金森病(PD)和中風(fēng)(Stroke)等,在老年人中的發(fā)病率居高不下,嚴(yán)重威脅人類的生命健康[3-5]?,F(xiàn)代研究證實(shí),這些神經(jīng)系統(tǒng)疾病均是由神經(jīng)細(xì)胞損傷引起的,因此,開發(fā)安全高效的治療神經(jīng)細(xì)胞損傷的藥物仍然是藥物研究的重要方向[6]。川芎嗪(TMP)為傳統(tǒng)中藥傘形科植物川芎根莖中的有效化學(xué)成分,已被廣泛用于治療缺血性腦中風(fēng)[7-8]?,F(xiàn)代藥理學(xué)研究表明,TMP能較快地通過血腦屏障,具有抗氧化、抗自由基、 Ca2+拮抗、抑制血小板聚集、防止血栓形成等作用,有助于神經(jīng)細(xì)胞恢復(fù)治療[9-11]。為了進(jìn)一步提高TMP的神經(jīng)保護(hù)活性,本課題組借鑒“中藥配伍法則·化藥拼合原理”研究思路,以TMP和其他具有神經(jīng)保護(hù)效應(yīng)的中藥成分為原料,設(shè)計(jì)合成了一系列川芎嗪衍生物[12-14]。經(jīng)實(shí)驗(yàn)驗(yàn)證,這些川芎嗪衍生物對(duì)損傷的PC12細(xì)胞具有保護(hù)作用,其中T-VA對(duì)CoCl2損傷的PC12細(xì)胞保護(hù)作用最強(qiáng)(EC50=4.25 μmol/L)[12]。研究還發(fā)現(xiàn),T-VA能夠調(diào)控核轉(zhuǎn)錄因子(NF-κB/p65)和環(huán)氧合酶(COX-2)的表達(dá),且能改善中腦動(dòng)脈栓塞(MCAO)模型大鼠的運(yùn)動(dòng)功能[15]。T-VA的分子式為C24H28N4O4,其結(jié)構(gòu)示于圖1。
圖1 候選藥物T-VA的結(jié)構(gòu)Fig.1 Structure of innovative drug T-VA
液相色譜-質(zhì)譜(LC/MS)聯(lián)用技術(shù)因結(jié)合了液相色譜的分離能力和質(zhì)譜的靈敏度高、專屬性強(qiáng)的檢測(cè)能力,現(xiàn)已成為藥物代謝研究的有力工具和代謝物結(jié)構(gòu)分析的重要方法[16-17]。線性離子阱-靜電場(chǎng)軌道阱串聯(lián)質(zhì)譜(LTQ-Orbitrap MS)的分辨率高達(dá)100 000,質(zhì)量精度高達(dá)2×10-6,能夠?qū)δ繕?biāo)物進(jìn)行多級(jí)質(zhì)譜分析,因此可在沒有標(biāo)準(zhǔn)物質(zhì)的情況下,通過精確分子質(zhì)量對(duì)未知物進(jìn)行快速篩查與結(jié)構(gòu)確證[18-19]。
目前,已有一些對(duì)川芎中內(nèi)酯類化合物及川芎嗪衍生物的質(zhì)譜學(xué)研究報(bào)道[20-21],但對(duì)候選藥物T-VA的質(zhì)譜裂解規(guī)律及其在大鼠體內(nèi)代謝的質(zhì)譜解析尚無研究。本工作擬采用LC/LTQ-Orbitrap MS技術(shù),通過分析T-VA與其代謝產(chǎn)物的主要碎片離子峰、質(zhì)譜特征與結(jié)構(gòu)信息,闡明T-VA在大鼠體內(nèi)的代謝途徑。同時(shí)還借鑒藥物化學(xué)的方法,合成得到了代謝產(chǎn)物實(shí)體,根據(jù)質(zhì)譜特征驗(yàn)證其與代謝產(chǎn)物結(jié)構(gòu)的一致性,并借助PC12細(xì)胞模型驗(yàn)證代謝產(chǎn)物的神經(jīng)保護(hù)活性,希望為進(jìn)一步研究T-VA的生物轉(zhuǎn)化過程與前藥修飾提供重要信息。
1.1 主要儀器與裝置
Accela 600 pump 高效液相色譜-LTQ-Orbitrap XL質(zhì)譜聯(lián)用儀:美國Thermo Scientific公司產(chǎn)品,配有電噴霧離子源(ESI)、在線脫氣機(jī)、自動(dòng)進(jìn)樣器、高壓二元梯度泵和Metworks 2.0數(shù)據(jù)處理系統(tǒng);RCT基本型雙線恒溫加熱磁力攪拌器:德國IKA公司產(chǎn)品;BSA224S-CW型分析天平:德國賽多利斯公司產(chǎn)品;AM-500核磁共振儀:瑞士Bruker公司產(chǎn)品;Forma 3111 CO2培養(yǎng)箱,Multiskan GO全波長(zhǎng)酶標(biāo)儀:均為美國Thermo Fisher公司產(chǎn)品。
1.2 材料、試劑與實(shí)驗(yàn)動(dòng)物
化合物T-VA:由本實(shí)驗(yàn)室合成[12],經(jīng)HPLC面積歸一化法測(cè)定其純度大于97%;乙腈、甲醇和甲酸:色譜純,美國Fisher公司產(chǎn)品;對(duì)甲苯磺酰氯、香草酸、氯化亞砜、碳酸鉀、N,N-二甲基甲酰胺(DMF)、四氫呋喃(THF)和無水甲醇:均為分析純或化學(xué)純;PC-12細(xì)胞:由北京協(xié)和細(xì)胞資源中心提供;Gibco 1640培養(yǎng)基、胎牛血清、馬血清和神經(jīng)生長(zhǎng)因子:美國Thermo Fisher公司產(chǎn)品;四甲基偶氮唑藍(lán)(MTT):美國Sigma公司產(chǎn)品;雄性SD大鼠(質(zhì)量240~260 g):由北京維通利華實(shí)驗(yàn)動(dòng)物技術(shù)有限公司提供。
1.3 實(shí)驗(yàn)條件
1.3.1 色譜條件 色譜柱:Agilent Zorbax SB C18柱(250 mm×4.6 mm×5 μm);HPLC流動(dòng)相:A為0.1%甲酸水溶液,B為甲醇;梯度洗脫程序:0~20 min(70%B~85%B);流速1.0 mL/min;柱溫25 ℃;進(jìn)樣量10 μL。
1.3.2 質(zhì)譜條件 電噴霧離子源(ESI)正離子模式;質(zhì)量掃描范圍m/z50~1 000;噴霧電壓3.0 kV;毛細(xì)管溫度300 ℃;鞘氣流速30 L/h;輔助氣流速180 L/h。分析時(shí),先采取高分辨傅里葉全掃描采集一級(jí)質(zhì)譜,然后采用二維線性離子阱(LTQ)采集二級(jí)和三級(jí)質(zhì)譜,自動(dòng)選取上一級(jí)最強(qiáng)離子峰進(jìn)行碰撞誘導(dǎo)解離裂解,碰撞能量為30%。
1.4 實(shí)驗(yàn)方法
1.4.1 樣品制備 雄性SD大鼠給藥前12 h禁食,自由飲水,給藥組以120 mg/kg的用量灌胃給藥,空白對(duì)照組灌胃等量0.3% CMC-Na。3 h后,大鼠腹腔注射10%水合氯醛麻醉,腹主動(dòng)脈取血,注入肝素鋰采血管中,以3 000 r/min離心10 min,取上清液;加入3倍量的乙腈,渦旋充分混勻,再以10 000 r/min離心15 min,取上清液,氮?dú)獯蹈珊笥眉状既芙猓?jīng) 0.45 μm濾頭過濾,于-20 ℃保存,備用。
1.4.2 代謝產(chǎn)物M1的合成 將2-羥基-3,5,6-三甲基吡嗪、氫氧化鉀置于單口瓶中,加入四氫呋喃混勻,在冰浴下加入對(duì)甲苯磺酰氯,于0 ℃攪拌0.5 h,然后緩慢升至室溫,繼續(xù)攪拌15 h。采用薄層色譜(thin layer chromatography, TLC)監(jiān)測(cè),待原料基本消失,停止反應(yīng),向反應(yīng)液中加水分散,經(jīng)乙酸乙酯萃取,蒸干,殘留物用硅膠減壓蒸干拌樣,硅膠柱洗脫,得到白色固體。將香草酸置于單口瓶中,加入無水甲醇,待完全溶解后,在冰浴下緩慢滴加氯化亞砜,于0 ℃下攪拌0.5 h,然后緩慢升至室溫,繼續(xù)攪拌15 h。采用TLC監(jiān)測(cè),待原料基本消失,停止反應(yīng),將反應(yīng)液減壓蒸干,得到白色固體。將前兩步反應(yīng)產(chǎn)物與碳酸鉀置于單口瓶中,加入N,N-二甲基甲酰胺,在氮?dú)獗Wo(hù)下于70 ℃攪拌15 h。采用TLC監(jiān)測(cè),待原料基本消失,停止反應(yīng),加水分散,用二氯甲烷萃取,蒸干,殘留物用硅膠減壓蒸干拌樣,硅膠柱洗脫,得到代謝產(chǎn)物M1。其詳細(xì)的合成路線示于圖2。
1.4.3 代謝產(chǎn)物M1的神經(jīng)保護(hù)活性評(píng)價(jià)
參考本課題組前期工作[12-14],用85% RPMI 1640細(xì)胞培養(yǎng)基、5%胎牛血清、10%馬血清,再加入100 U/mL雙抗,配制完全培養(yǎng)基。當(dāng)細(xì)胞濃度達(dá)到80%時(shí),倒掉原培養(yǎng)基,加入 RPMI 1640,饑餓細(xì)胞14 h后,以每孔120 μL接種于多聚賴氨酸包被過的96孔板中,用90% RPMI 1640、10%胎牛血清、100 U/mL雙抗配制培養(yǎng)基培育,每孔細(xì)胞濃度約為7×103。另加入0.05 mg/L的NGF誘導(dǎo)細(xì)胞分化,分化培養(yǎng)48 h。用DMSO溶解化合物,培養(yǎng)基稀釋,以濃度分別為3.75、7.50、15、30、60 μmol加藥,每一濃度平行4孔,對(duì)照組加入等體積培養(yǎng)液,DMSO的終濃度小于0.1%。36 h后,添加終濃度為300 μmol CoCl2損傷細(xì)胞。12 h后加20 μL(5 g/L)MTT,培養(yǎng)4 h,去掉上清液,每孔加入100 μL DMSO,振蕩5 min,測(cè)定490 nm處各孔的吸光度。按式(1)計(jì)算細(xì)胞增殖率。
[A490(Compd)-A490(CoCl2)]/
[A490(NGF)-A490(CoCl2)]×100%
(1)
圖2 代謝產(chǎn)物M1的合成路線Fig.2 Synthesis route of M1
2.1 T-VA的ESI-MSn分析結(jié)果
采用正離子模式對(duì)T-VA進(jìn)行ESI-MSn分析,得到的質(zhì)譜圖示于圖3。圖3a中可見T-VA的準(zhǔn)分子離子峰m/z437 [M+H]+;圖3b中可見m/z437 [M+H]+及其裂解碎片m/z285、151;圖3c是對(duì)m/z285進(jìn)一步做三級(jí)質(zhì)譜掃描,得到m/z151、123碎片峰?;衔颰-VA在上述質(zhì)譜條件下發(fā)生離子化,川芎嗪與香草酸的連接鍵(酯鍵和醚鍵)均存在發(fā)生斷裂的可能性,不能明確得出其中基團(tuán)斷裂的先后順序。因此,只能推斷化合物T-VA可能的裂解途徑,示于圖4。
注:a.MS1;b.MS2 of m/z 437;c.MS3 of m/z 285圖3 候選藥物T-VA的MSn質(zhì)譜圖Fig.3 Mass spectrum of innovative drug T-VA
圖4 T-VA可能的裂解途徑Fig.4 Possible fragmentation pathway of T-VA
2.2 T-VA大鼠體內(nèi)代謝產(chǎn)物的鑒定
空白大鼠血漿、給藥大鼠血漿、給藥大鼠血漿扣除背景后的總離子流圖示于圖5。與空白組血樣比較,對(duì)給藥大鼠血漿的總離子流圖進(jìn)行背景扣除后,除原型藥M0外,在給藥大鼠血樣中還監(jiān)測(cè)到1種主要代謝產(chǎn)物M1。
在一級(jí)全掃描質(zhì)譜中,M0的準(zhǔn)分子離子峰為m/z437[M+H]+,色譜保留時(shí)間為6.25 min,裂解碎片為m/z285、151,其他色譜保留時(shí)間、準(zhǔn)分子離子及碎片離子均與化合物 T-VA相同,故確定M0為母體藥物T-VA。
在一級(jí)全掃描質(zhì)譜中,準(zhǔn)分子離子m/z317[M+H]+,色譜保留時(shí)間為5.09 min,比M0準(zhǔn)分子離子(m/z437)少 120 u,推測(cè)其為化合物T-VA母核脫去一分子川芎嗪的代謝物。經(jīng)碰撞誘導(dǎo)解離(CID),該離子產(chǎn)生的二級(jí)碎片離子為m/z285、135,與原型藥裂解規(guī)律類似,推斷M1為香草酸甲酸部位在體內(nèi)代謝發(fā)生甲酯化的結(jié)果,其結(jié)構(gòu)及可能的裂解途徑示于圖6。LTQ Orbitrap 高分辨質(zhì)譜儀可僅通過準(zhǔn)確的化合物質(zhì)量(在除質(zhì)量外其他條件未知的情況下)推測(cè)其分子式,并根據(jù)環(huán)雙鍵當(dāng)量值(RDB當(dāng)量值)確定正確的化合物分子式。采用該方法對(duì)M1的分子離子峰(m/z317.148 62)進(jìn)行分析,得到M1([M+H]+)的分子式為C17H21O4N2(RDB:8.5,delta(ppm):-3.038),與推斷結(jié)果相符合。
圖5 空白大鼠血漿(a)、給藥大鼠血漿(b)、給藥大鼠血漿扣除背景處理后(c)的總離子流圖Fig.5 Total ion chromatogram of control group (a), T-VA group (b), background deduction (c)
圖6 代謝產(chǎn)物M1的結(jié)構(gòu)及裂解規(guī)律Fig.6 Structure and possible fragmentation pathway of M1
2.3 代謝產(chǎn)物M1的合成及確認(rèn)
采用藥物化學(xué)的方法,合成得到推斷的代謝產(chǎn)物M1-1,經(jīng)1H-NMR、1C-NMR確定其結(jié)構(gòu)。M1-1為白色固體,產(chǎn)率52.5%,熔點(diǎn)140.0~140.7 ℃。1H-NMR(CDCl3)(ppm):7.62~7.64(dd,J=1.2,8.4 Hz,1H,Ar—H),7.53(d,J=1.2 Hz,1H,Ar—H),7.06(d,J=8.4 Hz,1H,Ar—H),5.26(s,2H,—CH2),3.88(s,6H,2×—OCH3),2.62(s,3H,—CH3),2.52(s,3H,—CH3),2.51(s,3H,—CH3)。13C-NMR(CDCl3)(ppm):166.95(—COO—),151.99,151.39,150.12,149.30,148.91,145.41,123.41,114.38,112.82,112.51,70.81(—CH2),56.12(—OCH3),52.16(—OCH3),21.70(—CH3),21.51(—CH3),20.67(—CH3)。
M1與M1-1的質(zhì)譜圖示于圖7。合成得到M1-1的色譜保留時(shí)間為5.11 min,其分子離子峰為m/z317.148 35,二級(jí)裂解碎片為m/z285.077 70、134.923 80;而血漿中代謝產(chǎn)物M1的色譜保留時(shí)間為5.09 min,分子離子峰為m/z317.148 62,二級(jí)裂解碎片為m/z285.078 70、134.947 22。由此可見,合成得到的化合物與血漿中代謝產(chǎn)物的色譜、質(zhì)譜特征均吻合,據(jù)此可以確證M1為香草酸羧基部位在體內(nèi)代謝發(fā)生甲酯化的結(jié)果,而合成得到的M1-1即為M1。
2.4 代謝產(chǎn)物M1的神經(jīng)保護(hù)活性評(píng)價(jià)
前期關(guān)于代謝產(chǎn)物M1類化合物的構(gòu)效關(guān)
系研究表明,香草酸與川芎嗪拼合的醚鍵部分是活性藥效基團(tuán),而酯鍵區(qū)域可能發(fā)揮前藥作用,即保護(hù)化合物的活性,防止提前被代謝失活。選取CoCl2損傷的PC12細(xì)胞模型來驗(yàn)證代謝產(chǎn)物M1與T-VA類似的神經(jīng)保護(hù)活性,詳細(xì)數(shù)據(jù)列于表1。
圖7 M1(a.MS1,b.MS2)與M1-1(c.MS1,d.MS2)的質(zhì)譜圖Fig.7 Mass spectrum of M1(a.MS1, b.MS2) and M1-1(c.MS1, d.MS2)
化合物Compound細(xì)胞增殖率Cellproliferationrate/%60μmol/L30μmol/L15μmol/L7.5μmol/L3.75μmol/LEC50/(μmol/L)M184.8251.7247.4522.6232.1516.01
如表1所示,不同濃度下代謝產(chǎn)物M1對(duì)CoCl2損傷的PC12細(xì)胞均有一定的保護(hù)作用,擬合得EC50值為16.01 μmol/L,活性接近候選藥物T-VA。該結(jié)果表明,代謝產(chǎn)物M1與T-VA具有類似的神經(jīng)保護(hù)活性,T-VA可能通過體內(nèi)代謝脫去酯鍵連接的川芎嗪繼續(xù)發(fā)揮其活性作用。
本研究采用LC/LTQ-Orbitrap MS技術(shù)對(duì)候選藥物T-VA的裂解規(guī)律及體內(nèi)代謝進(jìn)行研究,建立了大鼠體內(nèi)T-VA及其代謝產(chǎn)物的LC/MSn檢測(cè)方法, 分析討論了T-VA及其代謝產(chǎn)物的主要碎片離子峰、質(zhì)譜特征與結(jié)構(gòu)信息,發(fā)現(xiàn)其在大鼠血漿內(nèi)的主要代謝產(chǎn)物M1為香草酸羧基部位脫吡嗪酯后發(fā)生甲酯化的結(jié)果。研究還借鑒藥物化學(xué)的方法,合成得到代謝產(chǎn)物實(shí)體,根據(jù)其質(zhì)譜特征對(duì)其進(jìn)行驗(yàn)證,并借助PC12細(xì)胞模型驗(yàn)證了代謝產(chǎn)物M1與T-VA具有類似的神經(jīng)保護(hù)活性,該結(jié)果可為進(jìn)一步研究其生物轉(zhuǎn)化過程與前藥修飾提供重要信息。
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Mass Fragmentation Pathway of a Candidate Drug T-VA and Its Metabolites in Rats
ZHANG Chen-ze1, YAN Meng-meng1, XU Bing1, LIN Hong-ying1, YAN Wen-qiang1, LIU Shuai1, CHEN Jing2, LIU Yong-gang1, WANG Peng-long1, LEI Hai-min1
(1.SchoolofChinesePharmacy,BeijingUniversityofChineseMedicine,Beijing100102,China;2.OfficeofTeachingAffairs,TibetTibetanCollege,Lhasa850000,China)
The candidate drug T-VA (C24H28N4O4) was synthesized using two kind of neuroprotective ingredients from Chinese traditional medicinal herbs, and displayed promising protective effect on the injured PC12 cells. In previous study, this beneficial effect was due to the modulation of nuclear transcription factor-κB/p65 (NF-κB/p65) and cyclooxygenase-2 (COX-2) expressions. T-VA also exhibited neuroprotective effect in a rat model of ischemic stroke with concomitant improvement of motor functions. Understanding drug metabolites contributes to discovering and developing the novel drug from the metabolites possessed the pharmacological activities. The structure profile of the metabolites provides an essential perspective for the synthetic refinement and the candidates among an extensive series of potential structures, resulting in an optimum drug effectiveness and safety. Liquid chromatography with electrospray ionization mass spectrometric detection (LC-ESI-MS) has been extensively utilized for the online analysis and structural characterization of the active ingredients and metabolites. Thus, there is a need to determine the primary metabolites and mass fragmentation pathways of T-VA in order to understand its potential pharmacological applications. It is a pathway via LC/LTQ-Orbitrap MS to investigate the mass fragmentation of a candidate drug T-VA and study its metabolites in rats. As a result, a method of LC/MSnwas established for the analysis of T-VA and its metabolites in rats. The fragmentation pathway of T-VA was explained using the Analyst V4.0 software. By further analysis of main fragment ions (m/z317, 285, 135) and structural information (C17H21O4N2, RDB:8.5, delta ppm:-3.038 ppm), M1 [methyl-3-methoxy-4-((3,5,6-trimethylpyrazin-2-yl)methoxy)benzoate] was discovered as one of the main metabolites. According to the suppositional structure of M1, M1-1 was synthesized via condensation reaction, which was determined by nuclear magnetic resonance spectrum (1H-NMR,13C-NMR) and HRMS. By comparing the mass spectrum characters and chromatographic features of M1-1 and M1, it can confirm the exact structure of M1. Furthermore, the neuroprotective effect of M1 in differentiated PC12 cells were evaluated. As a result, M1 in different concentrations could protect PC12 cells injured by CoCl2(EC50=16.01 μmol/L), which was close to T-VA. The result indicated that both T-VA and its main metabolite have neuroprotective effect, which provides references for further new drug design. In this study, metabolite of candidate drug T-VA was obtained by chemical synthesis and verified by MS technique, which provided a novel idea on the study of drug metabolism. M1 may become a potential neuroprotective agent and further studies are currently underway.
LC/LTQ-Orbitrap MS; candidate drug T-VA; mass fragmentation pathway; metabolite; chemical synthesis; neuroprotective activity
2016-07-11;
2016-10-19
國家自然科學(xué)基金面上項(xiàng)目(81173519);北京市中藥基礎(chǔ)與新藥研究重點(diǎn)實(shí)驗(yàn)室,北京中醫(yī)藥大學(xué)研究生自主課題(2016-JYB-XS117)資助
張晨澤(1992—),男(漢族),陜西人,碩士研究生,中藥化學(xué)專業(yè)。E-mail: zcz920418@163.com
王鵬龍(1985—),男(漢族),河北人,講師,從事中藥先導(dǎo)化合物發(fā)現(xiàn)研究。E-mail: wpl581@126.com
雷海民(1968—),男(漢族),陜西人,教授,從事中藥先導(dǎo)化合物發(fā)現(xiàn)與開發(fā)研究。E-mail: leihaimin@126.com
O657.63
A
1004-2997(2017)01-0067-08
10.7538/zpxb.2017.38.01.0067