高 明, 张争光, 李德江(三峡大学 化学与生命科学学院,湖北 宜昌 443002)
1,2,4-三唑并[3,4-b]-1,3,4-噻二唑类化合物具有多种药理活性,如杀虫、消炎、抗肿瘤、杀菌、舒张血管等[1~8]。若把两个1,2,4-三唑并[3,4-b]-1,3,4-噻二唑环构筑于同一分子,生成双稠杂环化合物,其生物活性可能会发生变化。文献[9,10]报道,双-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑类化合物具有更强的抗菌活性和抗癌活性。为此,本文以庚二羧和3-取代芳基-4-氨基-5-巯基-1,2,4-三氮唑(1a~1f)为原料,首次合成了未见文献报道的6种1,5-双三唑并噻二唑戊烷类衍生物(2a~2f, Scheme 1),其结构经1H NMR, IR, MS及元素分析表征。对2的抗菌活性进行了初步测试。
北京泰克有限公司X-4型熔点仪(温度计未经校正);Varian Mercury 400型400 MHz核磁共振仪(氘代三氟乙酸为溶剂,TMS为内标);NicoletNexus 470型红外光谱仪(KBr压);Finnigan Trace型质谱仪;Vario EL Ⅲ型元素分析仪。
Scheme 1
1a~1f参照文献[9]方法合成;其余所用试剂为国产(或进口)化学纯或分析纯。
在反应瓶中加入1 2.2 mmol,庚二酸1 mmol,四丁基碘化铵(TBAI)0.5 mmol及POCl37 mL,搅拌下于55 ℃~60 ℃反应3 h;回流反应7.0 h~9.0 h,减压蒸出过量的POCl3,倒入冰水中,剧烈搅拌直至油状物完全固化。用10%NaOH溶液调至pH10,抽滤,滤饼依次用水、乙醇洗涤,干燥后用DMF-乙醇重结晶得纯品2a~2f。
2a: 白色固体,产率73%, m.p.>250 ℃;1H NMRδ: 2.26~2.41(m, 6H, CH2), 3.42(t,J=7.5 Hz, 4H, SCCH2), 7.61~7.74(m, 6H, ArH), 8.25~8.36(m, 4H, ArH); IRν: 1 626, 1 243, 712 cm-1; MSm/z(%): 472(M+, 4), 297(25), 176(100), 102(87), 77(66); Anal.calcd for C23H20N8S2: C 58.45, H 4.27, N 23.71; found C 58.27, H 4.33, N 23.90。
2b: 灰色固体,产率60%, m.p.>250 ℃;1H NMRδ: 2.21~2.36(m, 6H, CH2), 3.49(t,J=7.4 Hz, 4H, SCCH2), 7.52~7.82(m, 3H, ArH), 7.89~8.04(m, 3H, ArH), 8.18~8.29 (m, 2H, ArH); IRν: 1 619, 1 262, 720 cm-1; MSm/z(%): 542(2), 540(M+, 3), 331(12), 210(46), 137(100), 111(31); Anal.calcd for C23H18N8S2Cl2: C 51.01, H 3.35, N 20.69; found C 51.22, H 3.24, N 20.51。
2c: 灰色固体,产率62%, m.p.>250 ℃;1H NMRδ: 2.24~2.35(m, 6H, CH2), 3.50(t,J=7.4 Hz, 4H, SCCH2), 7.49~7.76(m, 5H, ArH), 8.21~8.27(m, 3H, ArH); IRν: 1 631, 1 234, 718 cm-1; MSm/z(%): 542(2), 540(M+, 4), 331(18), 210(32), 137(100), 111(29); Anal.calcd for C23H18N8S2Cl2: C 51.01, H 3.35, N 20.69; found C 51.18, H 3.39, N 20.48。
2d: 灰色固体,产率67%, m.p.>250 ℃;1H NMRδ: 2.22~2.34(m, 6H, CH2), 3.46(t,J=7.4 Hz, 4H, SCCH2), 7.58~7.72(m, 4H, ArH), 8.17~8.23(m, 4H, ArH); IRν: 1 627, 1 230, 719 cm-1; MSm/z(%): 542(1), 540(M+, 2), 331(32), 210(28), 137(100), 111(54); Anal.calcd for C23H18N8S2Cl2: C 51.01, H 3.35, N 20.69; found C 51.20, H 3.47, N 20.52。
2e: 灰色固体,产率56%, m.p.>250 ℃;1H NMRδ: 2.27~2.32(m, 6H, CH2), 2.52(s, 6H, CH3), 3.40(t,J=7.3 Hz, 4H, SCCH2), 7.40~7.52(m, 3H, ArH), 7.51~7.62(m, 2H, ArH), 8.11~8.22(m, 3H, ArH); IRν: 1 632, 1 253, 714 cm-1; MSm/z(%): 500(M+, 1), 341(23), 190(31), 117(100); Anal.calcd for C25H24N8S2: C 59.97, H 4.83, N 22.38; found C 59.78, H 4.98, N 22.49。
2f: 灰色固体,产率60%, m.p.>250 ℃;1H NMRδ: 2.21~2.28(m, 6H, CH2), 2.48(s, 6H, CH3), 3.47(t,J=7.3 Hz, 4H, SCCH2), 7.40~7.64(m, 5H, ArH), 8.21~8.27(m, 3H, ArH); IRν: 1 624, 1 241, 711 cm-1; MSm/z(%): 500(M+, 2), 341(30), 190(27), 117(100); Anal.calcd for C25H24N8S2: C 59.97, H 4.83, N 22.38; found C 59.80, H 4.69, N 22.51。
环合过程中,由于1和庚二羧酸在POCl3中的溶解度较小,改用相转移催化剂TBAI,先在55 ℃~60 ℃反应3 h,然后升温回流反应9.0 h,以良好的产率得目标化合物。在没有催化剂的条件下,该反应也能进行,但产率较低。以2a为例,不用TBAI,产率仅40%,用TBAI后,产率达73%。由于1中N-NH2是作为亲核基团参与成环,所以当Ar为供电子基团时,有利于反应的进行;反之,若Ar为吸电子基团,则不利于反应进行。
在2a~2f的IR谱(略)中,C=N伸缩振动吸收出现在1 615 cm-1~1 640 cm-1; 1 250 cm-1附近的吸收峰为N-N=C吸收峰;C-S-C吸收峰出现在709 cm-1附近;在2a~2f的1H NMR谱(略)中,7.00~8.70的多重峰为芳环上质子的吸收峰;对2a~2f的质谱研究发现,它们均有很强的分子离子峰,分子离子峰与结构分子相吻合。
用杯盘培养法[10]测定了2a~2f[c(2)=100 mg·L-1]对金黄色葡萄球菌(S.aureus, A),大肠杆菌(E.coli, B)和枯草杆菌(B.subtilis, C)的抗菌活性(表1)。初步测试结果表明,2a~2f对以上三种细菌均有一定程度的抑制活性,其中2b,2c和2d对金黄色葡萄球菌的抑制活性和相同浓度用作参比的氯霉素(chlomycetin)的抑制活性相近。
表1 化合物的抗菌活性*Table 1 Antibacterial activity of compounds
*c(2 orchlomycetin)=100 mg·L-1; A.S.aureus; B.E.coli; C.B.subtilis; Zone diamerter of growth inhibition: <10 mm(-),10 mm~12 mm(+),13 mm~15 mm(++),16 mm~20 mm(+++); diamater of the cup=8 mm
[1] Marina Kritsanida, Anastasia Mouroutsou, Panagiotis Marakos,etal. Synthesis and antiviral activity evaluation of some new 6-substituted-(1-adamantyl)-1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles[J].Ⅱ Farmaco,2002,57:253-257.
[2] HU Guo-qiang, XIE Song-qiang. Synthesis and antibacterial activity of 8-substituted-phenyl-1-pyridin-3-yl-5H-bis[1,2,4]triazolo[3,4-b∶4′,3′-d][1,3,4]thiadiazines[J].Chinese Chemical Letters,2005,(16):723-726.
[3] Mohammad Amir, Harish Kumar, Sadique A Javed. Synthesis and pharmacological evaluation of condensedheterocyclic 6-substituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives of naproxen[J].Bioorganic & Medicinal Chemistry Letters,2007,17:504-508.
[4] Vinod Mathew, J Keshavayya, V P Vaidya,etal. Studies on synthesis and pharmacological activities of 3,6-disubstituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles and their dihydro analogues[J].European Journal of Medicinal Chemistry,2007,42:823-840.
[5] 惠新平,张艳,许鹏飞,等. 新型3-取代-6-(4-苯基)-7-(1H-1,2,4-三唑-1-基)[3,4 -b]-1″,3′,4′-噻二嗪衍生物的合成及抗菌活性[J].有机化学,2005,25(6):700-704.
[6] 刘方明,于建新,刘育亭,等. 新型3,6-二取代均三唑并[3,4-b]-噻二唑的合成[J].有机化学,1998,18:328-333.
[7] 张自义,李明,赵岚,等. 稠杂环化合物的研究(Ⅷ).3-(α-萘亚甲基)-6-烷基/芳基均三唑并[3,4-b]-噻二唑的合成及生物活性研究[J].高等学校化学学报,1993,14(4):512-516.
[8] 胡国强,张忠泉,许启泰,等. 相转移合成吡啶三唑并噻二唑及舒张血管活性研究[J].化学学报,2004,62(2):204-207.
[9] Holla B S, Gonsalves R, Shenoy S. Studies on someN-bridged heterocycles derived from bis-[4-amino-5-mercapto-1,2,4-triazol-3yl]alkenes[J].Ⅱ Farmco,1998,53:574-578.
[10] Holla B S, Poojary K N, Rao B S,etal. New bis-aminomercaptotrizoles and bis-triazolothiadiazoles as possible anticancer agents[J].J Med Chem,2002,37:511-517.