呂曉,葉可,馬旭軍,吳凱玥,黃蓉,艾洪蓮
(中南民族大學(xué) 藥學(xué)院,武漢 430074)
植物內(nèi)生真菌作為重要的與植物互作微生物類群,在與植物長(zhǎng)期的協(xié)同進(jìn)化過程中形成了特殊的互惠共生關(guān)系,具有極高的生物多樣性[1].從內(nèi)生真菌中分離得到的有生物活性天然產(chǎn)物數(shù)量和種類比任意其他微生物都多[2-3].這促使內(nèi)生真菌成為了尋找活性成分的潛在資源,為植物資源的保護(hù)提供了思路[4-5].湖北貝母(Fritillaria hupehensisHsiao et K.C.Hsia),是百合科貝母屬草本植物,其干燥鱗莖入藥. 微苦,性寒. 歸肺、心經(jīng)[6]. 用于熱痰咳嗽,痰核瘰疬,癰腫瘡毒. 本文以一株優(yōu)勢(shì)內(nèi)生真菌菌株Boeremia exigua為研究對(duì)象,對(duì)其固體發(fā)酵物的次生代謝產(chǎn)物進(jìn)行研究.分離純化得到了9個(gè)單體化合物(圖1),均為細(xì)胞松弛素類化合物.進(jìn)一步的抗炎活性檢測(cè)顯示,與陽(yáng)性藥PDTC相比,化合物1、2和3有著較好的抗炎活性,IC50分別為8.42、22.05和6.26μM, 為該類真菌抗炎藥物的研發(fā)提供了物質(zhì)基礎(chǔ).
圖1 化合物1~9的結(jié)構(gòu)Fig.1 Chemical structures of compounds 1-9
核磁共振波譜儀(AM600,德國(guó)Bruker).旋轉(zhuǎn)蒸發(fā)儀(SB-1300,ELELA),中壓液相色譜(puriflash 430,法國(guó)Interchim)制備、半制備高效液相色譜(1260型,美國(guó)Agilent),酶標(biāo)儀(瑞士TECAN).
正相柱色譜硅膠(80~100 目和200~300 目)和GF254薄層色譜板(青島海洋化工廠);Sephadex LH-20凝膠材料(瑞典Amersham Bioscience);反相柱色譜材料Chromatorex(40~75μm)(日本富士);色譜柱為Agilent Zorbax SB-18(4.6 mm×150 mm,5μm)和Agilent Zorbax SB-C18 柱(9.4 mm×150 mm,5μm).顯色方法為紫外燈下波長(zhǎng)254 nm和365 nm處觀察熒光,香草醛顯色及10%硫酸乙醇溶液顯色劑加熱顯色.
該內(nèi)生真菌分離自貝母新鮮植株的根部,貝母采自湖北省恩施州恩施市新塘鄉(xiāng)雙河社區(qū),菌株自編號(hào)為貝21.通過ITS序列測(cè)定結(jié)果對(duì)比得知,該序列與Boeremia exigua的最大相似度達(dá)100%.基因庫(kù)登錄號(hào)為MT154621.1.故將其鑒定為Boeremia exigua.該菌株保藏于中南民族大學(xué)藥學(xué)院微生物菌種庫(kù).
其具體分離過程為:貝母新鮮塊根自來水沖洗干凈后切成小段,75%乙醇潤(rùn)洗60 s,無菌水漂洗3 次. 0.1%升汞浸泡消毒40 s,無菌水漂洗3 次.吸干水分,剪去貝母根部?jī)啥说那锌诤髲闹袆濋_.將這些小塊接至PDA培養(yǎng)基(含青鏈霉素混合液)中,置于25 ℃的恒溫培養(yǎng)箱培養(yǎng).待真菌長(zhǎng)出后,挑取菌絲進(jìn)行純化培養(yǎng)得單一菌株.
本研究采用大米固體發(fā)酵培養(yǎng). 培養(yǎng)基:每瓶大米50 g,加水50 mL,共340瓶,置于500 mL培養(yǎng)瓶中經(jīng)120 ℃高溫滅菌.培養(yǎng)條件:25 ℃下暗培養(yǎng)30 d.
將發(fā)酵后的固體培養(yǎng)基用甲醇浸泡3 次,每次6 h.合并提取液,減壓濃縮蒸干有機(jī)試劑后,用水溶解,并用乙酸乙酯萃取3次,將乙酸乙酯部分合并濃縮得到粗浸膏900 g.浸膏經(jīng)正相硅膠柱層析(四氟層析柱,100 mm ×1000 mm,氯仿-甲醇:100∶0 →0∶100)梯度洗脫得到6 個(gè)組分(A~E). 組分B 經(jīng)中壓液相色譜(色譜柱型號(hào):YMC-Pack ODS-A,S-5 μm,12 nm,AA12S05-2510 WT,水-甲醇:80∶20 →0∶100)分離,得到4 個(gè)亞組分B1~B4.B2 中有結(jié)晶析出,清洗后得到化合物1.將晶體母液經(jīng)制備型高效液相色譜分離(色譜柱型號(hào):YMC-Pack ODS-A,S-5 μm,12 nm,AA12S05-1510 WT,水-乙腈80 ∶20 →0∶100)得到化合物2. B3 經(jīng)正相硅膠柱層析(四氟層析柱,石油醚-丙酮80∶20 →0∶100)分離得到5 個(gè)組分(B3-1~B3-5).B3-3 再經(jīng)制備行高效液相色譜分離純化得到化合物4. B3-5 經(jīng)凝膠柱色譜分離得到8 個(gè)組分(B3-5a~B3-5h). B3-5h 經(jīng)高效液相色譜(色譜柱型號(hào):YMC-Pack ODS-A,S-5 μm,12 nm,AA12S05-1510 WT,水-乙腈80∶20 →0∶100)分離純化,得到化合物3 和5.組分C 經(jīng)中壓液相色譜(色譜柱型號(hào):YMC-Pack ODS-A,S-5 μm,12 nm,AA12S05-2510 WT,水-甲醇:80∶20 →0∶100)分離得到6 個(gè)亞組分(C1~C-6).C2 經(jīng)正相硅膠柱層析(四氟層析柱,氯仿-甲醇80∶20 →0∶100)得到7個(gè)組分(C2-1~C2-7),C2-6和C2-7經(jīng)制備型高效液相色譜(色譜柱型號(hào):YMC-Pack ODS-A,S-5 μm,12 nm,AA12S05-1510 WT,水-乙腈80∶20 →0∶100)分離純化,得到化合物6、7、8和9.
采用Lipopolysaccharide(LPS)誘導(dǎo)的RAW 264.7 巨噬細(xì)胞產(chǎn)生NO 的炎癥效應(yīng)來檢測(cè)化合物1~9 的抗炎活性. 在含10%胎牛血清、100 U/mL 青霉素和100 g/mL 鏈霉素的dulbecco′s modified eagle medium(DMEM)培養(yǎng)基于恒溫培養(yǎng)箱中傳代培養(yǎng)(5%CO2,37 ℃).將RAW 264.7 細(xì)胞(5×105細(xì)胞/mL)接種到96孔多孔板中培養(yǎng)12 h后,用不同濃度的測(cè)試化合物(10~40 mM)處理2 h,然后在有無脂多糖(500 ng/mL)的情況下孵育24 h.除去培養(yǎng)基,在每孔中加入100 μmol/mL 3-(4,5)-dimethylthiahiazo(-zy1)-3,5-di- phenytetrazoliumromide(MTT) 溶 液(0.5 mg/mL),隨后在37 ℃下培養(yǎng)4 h,每個(gè)孔用150 μL DMSO 溶解晶體.酶標(biāo)儀570 nm 處測(cè)吸光度,細(xì)胞存活率為對(duì)照的百分比來表示.使用Griess 試劑盒收集細(xì)胞上清液,以測(cè)量上清液中NO 的產(chǎn)生.使用酶標(biāo)儀在540 nm處測(cè)量吸光度.陽(yáng)性對(duì)照藥為Pyrrolidinedithiocarbamate(簡(jiǎn)稱PDTC).
化合物1:分子式為C29H37NO5,白色粉末.1H NMR(CD3OD,600 MHz):δH7.27(2H,t,J= 7.4 Hz,H-3′,5′),7.19(1H,t,J=7.4 Hz,H-4′),7.14(2H,d,J=7.4 Hz,H-2′,6′),6.93(1H,dd,J=15.7,4.4 Hz,H-21),5.83(1H,ddd,J=15.0,9.9,1.6 Hz,H-13),5.78(1H,dd,J=15.7,1.8,H-22),5.29(H1,s,H-12a),5.24(1H,m,H-14),5.09(1H,s,H-12b),4.45(1H,m,H-20),3.80(1H,d,J= 11.0 Hz,H-7),3.39(1H,m,H-8),3.37(1H,m,H-3),3.21(1H,m,H-5),2.85(1H,dd,J=5.3,2.7 Hz,H-4),2.80(2H,m,H-10),2.09(1H,m,H-19a),1.91(1H,m,H-15a),1.72(1H,m,H-17a),1.66(1H,m,H-19b),1.56(1H,m,H-15b),1.45(1H,m,H-18a),1.28(1H,m,H-18b),1.22(1H,m,H-16),0.88(3H,d,J =6.6 Hz,H-24),0.86(3H,d,J =6.8 Hz,H-11),0.58(1H,m,H-17b).13C NMR(CD3OD,150 MHz):δc174.0(C-1),166.4(C-23),154.7(C-21),151.5(C-6),138.3(C-1′),136.7(C-14),131.0(C-6′),131.0(C-2′),129.6(C-3′),129.6(C-5′),128.7(C-13),127.9(C-4′),119.5(C-22),114.3(C-12),85.4(C-9),71.5(C-7),71.1(C-20),54.8(C-3),49.4(C-8),49.0(C-4),44.0(C-10),43.2(C-19),36.6(C-17),35.4(C-15),34.5(C-16),32.8(C-5),21.5(C-18),20.7(C-24),14.1(C-11).以上數(shù)據(jù)與文獻(xiàn)[7]數(shù)據(jù)基本一致,故化合物1被確定為Cytochalasin B.
化合物2:分子式為C29H37NO5,白色粉末.1H NMR(CD3OD,600 MHz):δH7.31(2H,t,J =7.6 Hz,H-3′,5′),7.23(1H,m,H-4′),7.14(1H,m,H-21),7.12(2H,m,H-2′,6′),6.10(1H,ddd,J =15.2,10.1,1.8 Hz,H-13),5.97(1H,dd,J =15.7,2.0 Hz,H-22),5.22(1H,m,H-14),4.57(1H,m,H-20),3.87(1H,m,H-7),3.56(1H,s,H-4),3.51(1H,dd,J =9.9,5.3 Hz,H-3),3.24(1H,t,J=10.1,H-8),3.00(1H,dd,J=13.0,5.3 Hz,H-10a),2.69(1H,dd,J =13.0,9.9 Hz,H-10b),2.08(1H,m,H-15a),1.96(1H,m,H-19a),1.74(1H,m,H-17a),1.67(1H,m,H-15b),1.63(3H,s,H-12),1.58(1H,m,H-19b),1.58(2H,m,H-18),1.28(3H,s,H-11),1.27(1H,m,H-16),0.89(3H,d,J =6.7 Hz,H-24),0.59(1H,m,H-17b).13C NMR(CD3OD,150 MHz):δc174.6(C-1),166.4(C-23),155.3(C-21),138.8(C-1′),136.4(C-14),135.1(C-6),131.0(C-2′),131.0(C-6′),129.8(C-3′),129.8(C-5′),129.2(C-13),127.9(C-4′),126.7(C-5),119.5(C-22),85.8(C-9),71.7(C-7),70.6(C-20),60.6(C-3),50.4(C-8),44.1(C-10),43.5(C-15),36.9(C-17),35.3(C-19),34.7(C-16),21.3(C-18),20.8(C-24),17.6(C-11),14.7(C-12).以上數(shù)據(jù)與文獻(xiàn)[8]數(shù)據(jù)基本一致,故化合物2被確定為Cytochalasin B2.
化合物3:分子式為C29H37NO5,無色油狀.1H NMR(CDCl3,600 MHz):δH7.33(2H,t,J =7.5 Hz,H-3′,5′),7.26(1H,m,H-4′),7.14(2H,m,H-2′,6′),7.04(1H,dd,J =15.7,3.9 Hz,H-21),6.08(1H,ddd,J=15.1,10.0,1.9 Hz,H-13),5.93(1H,dd,J =15.7,2.0 Hz,H-22),5.30(1H,ddd,J =15.1,10.9,3.7 Hz,H-14),4.54(1H,s,H-20),3.68(1H,t,J=7.1 Hz,H-3),3.13(1H,dd,J=10.0,5.4 Hz,H-8),2.85(1H,d,J=5.8 Hz,H-4),2.78-2.80(2H,m,H-10),2.74(1H,d,J =5.4 Hz,H-7),2.33(1H,m,H-5),2.08(1H,m,H-15a),1.93(1H,m,H-19a),1.72(1H,m,H-15b),1.63(1H,m,H-19b),1.62(1H,m,H-17a),1.49(1H,m,H-18a),1.24(1H,m,H-18b),1.23(3H,s,H-12),1.22(1H,m,H-16),1.01(3H,d,J =7.2 Hz,H-11),0.87(3H,d,J=6.6 Hz,H-24),0.65(1H,m,H-17b).13C NMR(CDCl3,150 MHz):δc172.6(C-1),164.7(C-23),152.6(C-21),137.0(C-1′),136.0(C-14),129.4(C-2′),129.4(C-6′),129.1(C-3′),129.1(C-5′),127.3(C-4′),126.5(C-13),118.8(C-22),84.6(C-9),70.5(C-20),61.1(C-7),57.5(C-6),54.0(C-3),49.2(C-4),46.1(C-8),45.2(C-10),41.9(C-15),36.1(C-5),35.4(C-17),34.8(C-19),33.2(C-16),20.5(C-24),20.2(C-18),19.7(C-12),12.9(C-11).以上數(shù)據(jù)與文獻(xiàn)[9]數(shù)據(jù)基本一致,故化合物3被確定為Cytochalasin F.
化合物4:分子式為C29H37NO5,白色粉末.1H NMR(CD3OD,600 MHz):δH7.27(2H,d,J =7.5 Hz,H-3′,5′),7.19(3H,m,H-2′,4′,6′),6.99(1H,dd,J =15.6,5.7 Hz,H-21),5.91(1H,ddd,J =15.0,10.2,2.0 Hz,H-13),5.78(1H,dd,J =15.6,1.6 Hz,H-22),5.57(1H,m,H-7),5.26(1H,ddd,J =15.0,10.8,3.1 Hz,H-14),4.39(1H,m,H-20),4.07(2H,br s,H-12),3.45(1H,m,H-3),3.42(1H,m,H-8),2.95(1H,m,H-5),2.88(2H,m,H-10),2.75(1H,t,J=4.4 Hz,H-4),2.11(1H,m,H-15a),1.89(1H,m,H-19a),1.75(1H,m,H-17a),1.69(1H,m,H-15b),1.58(1H,m,H-19b),1.44(1H,m,H-18a),1.37(1H,m,H-18b),1.31(1H,m,H-16),1.09(3H,d,J=7.3 Hz,H-11),0.89(3H,d,J =6.6 Hz,H-24),0.62(1H,m,17b).13C NMR (CD3OD,150 MHz):δc174.2(C-1),166.5(C-23),154.3(C-21),145.1(C-6),138.6(C-1′),135.6(C-14),131.0(C-2′),131.0(C-6′),129.6(C-3′),129.6(C-5′),129.6(C-13),127.8(C-4′),126.7(C-7),120.0(C-22),88.6(C-9),71.7(C-20),63.3(C-12),57.2(C-3),51.0(C-4),46.6(C-8),44.2(C-10),42.6(C-15),36.2(C-17),35.5(C-19),35.0(C-16),34.4(C-5),21.6(C-18),20.7(C-24),13.1(C-11).以上數(shù)據(jù)與文獻(xiàn)[10]數(shù)據(jù)基本一致,故化合物4被確定為Cytochalasin Z2.
化合物5:分子式為C29H37NO4,白色粉末.1H NMR(CDCl3,600 MHz):δH7.32(2H,t,J=7.5 Hz,H-3′,5′),7.26(1H,m,H-4′),7.19(2H,d,J =7.5 Hz,H-2′,6′),7.07(1H,dd,J =15.6,6.4 Hz,H-21),5.91(1H,m,H-13),5.88(1H,m,H-22),5.51(1H,m,H-7),5.30(1H,ddd,J =14.4,10.7,3.1 Hz,H-14),4.45(1H,m,H-20),3.32(1H,d,J =10.1 Hz,H-3),3.13(1H,m,H-4),2.92(1H,m,H-5),2.89(2H,m,H-10),2.74(1H,t,J=3.1,H-8),2.11(1H,m,H-15a),1.89(1H,m,H-19a),1.77(3H,s,H-12),1.76(1H,m,H-17a),1.68(1H,m,H-15b),1.58(1H,m,H-19b),1.47(1H,m,H-15b),1.38(2H,m,H-18),1.25(1H,m,H-16),1.23(3H,d,J =7.3 Hz,H-11),0.88(3H,d,J=6.6 Hz,H-24),0.72(1H,m,H-17b).13C NMR(CDCl3,150 MHz):δc171.8(C-1),165.0(C-23),151.6(C-21),140.4(C-6),138.0(C-1′),134.5(C-14),129.2(C-2′),129.2(C-6′),129.1(C-3′),129.1(C-5′),128.6(C-13),127.1(C-4′),124.3(C-7),120.2(C-22),86.6(C-9),71.6(C-20),56.0(C-3),51.8(C-8),46.1(C-4),44.3(C-10),41.3(C-19),34.8(C-17),34.7(C-15),34.5(C-16),33.1(C-5),20.6(C-18),20.4(C-12),20.2(C-24),14.3(C-11).以上數(shù)據(jù)與文獻(xiàn)[11]數(shù)據(jù)基本一致,故化合物5被確定為Cytochalasin T.
化合物6:分子式為C29H37NO5,白色粉末.1H NMR(CD3OD,600 MHz):δH7.32(2H,t,J =7.5 Hz,H-3′,5′),7.23(1H,m,H-4′),7.17(2H,m,H-2′,6′),6.09(1H,ddd,J=15.2,9.7,2.0,H-13),5.59(1H,ddd,J=15.2,10.8,3.5 Hz,H-14),5.32(1H,s,H-12a),5.04(1H,s,H-12b),4.19(1H,m,H-21),3.87(1H,d,J =9.7 Hz,H-7),3.68(1H,m,H-20),3.37(1H,m,H-3),3.00(1H,dd,J= 19.4,6.7 Hz,H-22a),2.89(1H,t,J =9.7 Hz,H-8),2.85(1H,m,H-5),2.82(1H,m,H-22b),2.77(1H,dd,J =13.2,5.9 Hz,H-10a),2.46(1H,m,H-4),2.44(1H,m,H-10b),2.16(1H,m,H-15a),1.71(1H,m,H-15b),1.47(1H,m,H-19a),1.41(1H,m,H-16),1.35(2H,m,H-18),1.20(1H,m,H-17a),1.20(1H,m,H-17b),0.96(3H,d,J =6.6 Hz,H-24),0.67(3H,d,J =6.7 Hz,H-11).13C NMR(CD3OD,150 MHz):δc208.8(C-23),176.3(C-1),150.6(C-6),139.5(C-14),138.6(C-1′),130.8(C-2′),130.8(-6′),129.7(3′),129.7(C-5′),127.8(C-4′),127.7(C-13),114.7(C-12),75.3(C-20),72.3(C-7),70.5(C-21),64.5(C-9),54.9(C-3),49.0(C-8),48.0(C-4),44.0(C-10),42.4(C-15),40.4(C-22),35.3(C-17),32.7(C-16),32.4(C-5),30.5(C-19),23.1(C-18),22.9(C-24),13.2(C-11).以上數(shù)據(jù)與文獻(xiàn)[12]數(shù)據(jù)基本一致,故化合物6被確定為Multriostratin B.
化合物7:分子式為C29H37NO6,無色針晶.1H NMR(CD3OD,600 MHz):δH7.26(2H,t,J =7.6 Hz,H-3′,5′),7.19(1H,m,H-4′),7.13(2H,m,H-2′,6′),6.88(1H,dd,J =15.7,3.5 Hz,H-21),5.85(1H,dd,J =15.0,1.8 Hz,H-13),5.84(1H,dd,J =15.7,2.2 Hz,H-22),5.28(1H,s,H-12),5.19(1H,ddd,J=15.0,10.9,3.5 Hz,H-14),4.49(1H,m,H-20),3.79(1H,d,J =10.6 Hz,H-7),3.59(1H,m,H-19),3.40(1H,m,H-3),3.38(1H,m,H-8),3.22(1H,m,H-5),2.87(1H,dd,J =5.3,2.5 Hz,H-4),2.79(2H,d,J=6.0 Hz,H-10),2.09(1H,m,H-15a),1.64(1H,m,H-15b),1.54(1H,m,H-18a),1.54(1H,m,H-17a),1.44(1H,m,H-18b),1.16(1H,m,H-16),0.89(3H,d,J =6.6 Hz,H-24),0.87(3H,d,J =6.8 Hz,H-11),0.62(1H,m,H-17).13C NMR(CD3OD,150 MHz):δc174.0(C-1),166.2(C-23),151.4(C-21),151.4(C-6),138.1(C-1′),136.6(C-14),131.1(C-2′),131.1(C-6′),129.6(C-3′),129.6(C-5′),128.8(C-13),127.8(C-4′),119.6(C-22),114.4(C-12),85.5(C-9),75.2(C-19),74.5(C-20),71.5(C-7),54.7(C-3),44.0(C-10),43.3(C-15),35.1(C-16),33.8(C-17),32.8(C-5),31.0(C-18),20.7(C-24),14.1(C-11).以上數(shù)據(jù)與文獻(xiàn)[13]數(shù)據(jù)基本一致,故化合物7被確定為Zopfiellasins C.
化合物8:分子式為C29H37NO6,白色固體.1H NMR(CD3OD,600 MHz):δH7.27(2H,t,J =7.5 Hz,H-3′,5′),7.19(1H,t,J=7.5 Hz,H-4′),7.14(2H,d,J =7.5 Hz,H-2′,6′),7.03(1H,dd,J =15.6,5.1 Hz,H-21),5.84(1H,dd,J =15.6,1.7 Hz,H-22),5.77(1H,ddd,J =15.0,9.7,1.6 Hz,H-13),5.30(1H,s,H-12),5.25(1H,ddd,J =15.0,10.9,3.6 Hz,H-14),5.09(1H,s,H-12),4.13(1H,m,H-20),3.80(1H,d,J=11.0 Hz,H-7),3.72(1H,t,J=7.1 Hz,H-19),3.39(1H,m,H-3),3.31(1H,m,H-8),3.19(1H,m,H-5),2.83(1H,d,J =6.0 Hz,H-4),2.14(1H,m,H-15a),1.70(1H,m,H-18),1.68(1H,m,H-15b),1.62(1H,m,H-17a),1.50(1H,m,H-18b),1.34(1H,m,H-16),0.89(3H,d,J =6.6 Hz,H-24),0.87(3H,d,J =6.8 Hz,H-11),0.80(1H,m,H-17).13C NMR(CD3OD,150 MHz):δc173.9(C-1),166.2(C-23),151.5(C-6),151.0(C-21),138.3(C-1′),136.4(C-14),131.0(C-2′),131.0(C-6′),129.6(C-3′),129.6(C-5′),128.9(C-13),127.9(4′),121.1(C-22),114.3(C-12),85.4(C-9),76.1(C-20),74.3(C-20),71.2(C-7),54.9(C-3),43.9(C-10),43.2(C-15),33.5(C-16),32.9(C-5),30.6(C-17),29.7(C-18),20.5(C-24),14.3(C-11).以上數(shù)據(jù)與文獻(xiàn)[13]數(shù)據(jù)基本一致,故化合物8被確定為Zopfiellasins D.
化合物9:分子式為C29H37NO6,白色粉末.1H NMR(CD3OD,600 MHz):δH6.93(2H,d,J =8.5 Hz,H-2′,6′),6.89(1H,dd,J =15.7,4.1 Hz,H-21),6.67(2H,d,J =8.5 Hz,H-3′,5′),5.83(1H,ddd,J=15.0,9.7,1.6 Hz,H-13),5.76(1H,dd,J =15.7,1.8 Hz,H-22),5.28(1H,s,H-12a),5.21(1H,ddd,J =15.0,10.9,3.6 Hz,H-14),5.10(1H,s,H-12b),4.49(1H,m,H-20),3.79(1H,dd,J =10.8,1.6 Hz,H-7),3.38(1H,m,H-8),3.36(1H,m,H-5),3.23(1H,m,H-3),2.84(1H,dd,J =5.2,2.5 Hz,H-4),2.72(1H,dd,J =13.7,6.0 Hz,H-10a),2.66(1H,dd,J =13.7,5.3 Hz,H-10b),2.08(1H,m,H-15a),1.91(1H,m,H-19a),1.70(1H,m,H-15b),1.64(1H,m,H-17a),1.54(1H,m,H-19b),1.45(1H,m,H-18a),1.27(1H,m,H-16),1.20(1H,m,H-18b),0.92(3H,d,J =6.7 Hz,H-24),0.87(3H,d,J =6.6 Hz,H-11),0.56 (1H,m,H-17b).13C NMR(CD3OD,150 MHz):δc174.0(C-1),166.5(C-23),157.5(C-4′),154.8(C-21),151.5(C-6),136.6(C-14),132.1(C-2′),128.7(C-13),128.6(C-1′),119.2(C-22),116.3(C-3′),116.3(C-5′),114.3(C-12),85.5(C-9),71.5(C-7),71.1(C-20),54.9(C-3),49.9(C-8),48.2(C-4),43.2(C-10),42.8(C-19),36.6(C-17),35.3(C-15),34.6(C-16),32.9(C-5),21.4(C-18),20.7(C-24),14.2(C-11).以上數(shù)據(jù)與文獻(xiàn)[14]數(shù)據(jù)基本一致,故化合物9被確定為Cytochalasin Z5.
本文對(duì)分離到的化合物單體1~9均進(jìn)行了抗炎活性的檢測(cè),其中化合物1、2和3有較好的抗炎活性,IC50分別為8.42,22.05和6.26μM,如表1所示.
表1 化合物1~3的抗炎活性Tab.1 The anti-inflammatory activity of compounds 1-3
從湖北貝母內(nèi)生真菌Boeremia exigua中分離得到的9 個(gè)單體化合物,均為Cytochalasan 類化合物.這類化合物的特點(diǎn)是有高度氫化的異吲哚母核,并駢連碳環(huán)或者內(nèi)酯等大環(huán)[15]. 而且Cytochalasan 類化合物有著廣泛的生物活性,例如抗炎,殺線蟲,抗病原微生物,以及細(xì)胞毒等活性[16].本文報(bào)道了3個(gè)具有良好抗炎活性的Cytochalasan 類化合物的結(jié)構(gòu),其IC50值分別為8.42、22.05 和6.26 μM,為抗炎藥物的開發(fā)提供了潛在的先導(dǎo)化合物.