2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑的合成研究

以2-氯苯并噻唑为原料,在N,N-二异丙基乙基胺存在下与D或L-苯甘氨醇反应后,不经分离直接与甲磺酰氯在N,N-二异丙基乙基胺作用下关环,一锅法合成了(R)或(S)-2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑,利用IR、~1HNMR、MS谱和旋光度对其结构进行了表征.通过优化研究2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑的合成工艺条件,可得到总收率为80%的(R)或(S)-2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑.     

1-(5-甲基-1,3,4-噻二唑基)-3-苯基硫脲的合成及抑菌实验研究

以四丁基溴化铵为催化剂、5-甲基-2-氨基-1,3,4-噻二唑和苯异硫氰酸酯为原料,在乙腈溶剂中合成了1-(5-甲基-1,3,4-噻二唑基)-3-苯基硫脲,确定了优化的工艺条件,并对产物的抑菌活性进行了初步研究.     

2-(2-苯基-1,2,3-三唑-4-基)-5-氨基-1,3,4-噻二唑的一步合成

2,5-二取代-1,3,4-噻二唑类化合物具有良好的杀菌、杀虫、除草、消炎、止痛等生物活性,而2-烷基／芳杂环基-5-氨基-1,3,4-噻二唑同时又是一类非常重要的有机中间体,可用来合成具有生物活性的咪唑并噻二唑、噻二唑类席夫碱、含噻二唑环的苯甲酰脲、含噻二唑环的苯甲酰胺、含噻二唑环的苯基硫脲等。     

N-(5-苯基-1,3,4-噻二唑-2-基)-N′-氯代苯基脲类化合物的合成

2-氨基-5-苯基-1,3,4-噻二唑与氯代苯异氰酸酯反应合成了5种N-(5-烷基-1,3,4-噻二唑-2-基)-N′-取代苯基脲,产率为75%~82%。用核磁共振氢谱、红外光谱和元素分析确证了目标化合物的结构,初步的生物活性测定试验表明,该系列化合物具有一定的生物活性。     

2-巯基-5-甲氧基咪唑[4,5-b]并吡啶的合成工艺评价

2-巯基-5-甲氧基咪唑并[4,5-b]吡啶是合成新型咪唑并[4,5-b]吡啶类质子泵抑制剂的关键中间体.系统介绍了该化合物的合成方法,认为以2,6-二溴吡啶为原料的合成2-巯基-5-甲氧基咪唑并[4,5-b]吡啶,是值得重点开发的新工艺.     

阿卡他定关键中间体的合成研究

以5H-咪唑并[2,1-b]苯并吖庚因酮和N-甲基-4-哌啶酮为起始原料,经Mc Murry偶联反应得到阿卡他定的关键中间体11-(1-甲基-4-哌啶亚基)-6,11-二氢-5H-咪唑并[2,1-b]苯并吖庚因,含量95.0%,收率80.0%,其结构经MS、1H NMR、13C NMR确认。     

扁桃酸-噻二唑酰胺衍生物的合成及明胶酶抑制活性

为了寻找选择性高、亲和性强的新型明胶酶抑制剂类抗肿瘤药物,以(R)-(-)-扁桃酸与合成中间体5-取代-1,3,4-噻二唑-2-胺为原料,基于三甲基氯硅烷的羟基保护作用,经酰氯化、酰胺化等反应合成出12个扁桃酸-噻二唑酰胺衍生物,并对明胶酶(MMP-2,MMP-9)进行初步体外抑酶活性评价。结果显示,浓度为10μmol/L时,(2R)-N-[2-[5-(4-硝基苯基)-1,3,4-噻二唑]]-2-羟基-苯乙酰胺对MMP-2和MMP-9同时具有最强的抑制活性,抑制率分别为80.17%和70.16%,化合物(2R)-N-[2-[5-(3-硝基苯基)-1,3,4-噻二唑]]-2-羟基-苯乙酰胺、(2R)-N-[2-[5-苯甲基-1,3,4-噻二唑]]-2-羟基-苯乙酰胺和(2R)-N-[2-[5-(4-氯苯氧甲基)-1,3,4-噻二唑]]-2-羟基-苯乙酰胺对MMP-2有较强的抑制活性,化合物(2R)-N-[2-[5-苯甲基-1,3,4-噻二唑]]-2-羟基-苯乙酰胺、(2R)-N-[2-[5-苯乙基-1,3,4-噻二唑]]-2-羟基-苯乙酰胺和(2R)-N-[2-[5-(2,4-二氯苯氧甲基)-1,3,4-噻二唑]]-2-羟基-苯乙酰胺对MMP-9有中等强度的抑制活性。     

5-羟基-1,3,4-噻二唑[3,2-a]并嘧啶-7-酮衍生物的绿色合成

为了寻找干扰嘌呤核酸代谢的抗肿瘤新药,设计和合成了嘌呤生物碱的类似物。以2-氨基-1,3,4-噻二唑、丙二酸与三氯氧磷为原料,经过关环,偶合等反应合成了9种5-羟基-1,3,4-噻二唑[3,2-a]并嘧啶-7-酮衍生物,通过元素分析、IR、1 H NMR和质谱分析确定了其结构。     

糠醛缩2-氨基-5-甲基-1,3,4-噻二唑的合成

合成了2-氨基-5-甲基-1,3,4-噻二唑,并以此和糠酸为原料,合成了糠醛缩2-氨基-5-甲基-1,3,4-噻二唑Schiff碱,经IR、US和元素分析确证了其结构。初步抑菌实验表明,该Schiff碱具有一定的抗菌活性。     

5-亚氨基-7-氧代-6-芳基偶氮-1,3,4-噻二唑[3,2-a]并嘧啶衍生物的绿色合成

合成了5种新的5-亚氨基-7-氧代-6-芳基偶氮-1,3,4-噻二唑[3,2-a]并嘧啶衍生物,通过元素分析、IR、1HNMR和质谱分析确定了其结构.     

Pd2(dba)3-catalyzed amination of C5-bromo-imidazo[2,1-b][1,3,4] thiadiazole with substituted anilines at conventional heating in Schlenk tube

ABSTRACT

An efficient Pd₂(dba)₃-catalyzed amination of C5-bromo-imidazo[2,1-b][1,3,4]thiadiazole using conventional heating is reported. The C5-bromoimidazo[2,1-b][1,3,4]thiadiazole was synthesized using a multistep approach which started by cyclization of thiosemicarbazide with a carboxylic acid to give 2-amino[1,3,4]thiadiazoles which were further treated with 2-haloketones to give imidazo[2,1-b][1,3,4]thiadiazoles. Then, the bromination of imidazothiadiazole was done using N-bromosuccinimide to give the C5-bromo-imidazo[2,1-b][1,3,4]thiadiazole. Afterward, various C-N bond-forming approaches were attempted such as S_NAr, Cu(I), Cu(II), Pd(OAc)_2, Pd₂(dba)₃ catalyst with different ligand, additive, base, solvent and temperature conditions. Out of various approaches used, only Buchwald Hartwig amination, performed with conventional heating, gave N-arylamine-5-imidazothiadiazoles. Then, 10 different anilines with different electron-withdrawing and donating groups at different positions were employed to examine the scope and limitations of the method. Salient features of this method include conventional heating in a Schlenk tube as the reaction condition, the absence of the use of toxic isocyanides, the wide nature of substituent tolerance with anilines, and moderately good product yields.     

咪唑并[2,1-b]噻唑衍生物的合成及生物活性进展

根据环上取代基的不同咪唑并[2,1-b]噻唑衍生物具有多种多样的生物活性。通过对咪唑并[2,1-b]噻唑衍生物合成方法的不同进行分类,综述了近年来咪唑并[2,1-b]噻唑衍生物的合成及其生物活性,结果表明在咪唑并噻唑环上引入药理活性基团会增强其生物活性。咪唑并[2,1-b]噻唑环一般由Hanzstch方法合成,近年来也出现了一些新的合成方法,如Sonogashira、Suzuki反应和金属催化芳基化,对这些新方法合成咪唑并噻唑环及其衍生物也进行了综述。     

COMPARATIVE METABOLISM OF PHENANTHRO[3,4-B]THIOPHENE,PHENANTHRO[4,3-B]THIOPHENE AND THEIR CARBON ANALOG BENZO[C]PHENANTHRENE BY RAT LIVER MICROSOMES

Phenanthro[3,4-b]thiophene (P[3,4-b]T) and phenanthro[4,3-b]thiophene (P[4,3-b]T) are thiasters of weakly mutagenic benzo[c]phenanthrene (B[c]P). These polycyclic sulfur heterocycles (thia-PAHs) represent a group of chemicals which have been identified in cigarette smoke. P[3,4-b]T is a potent mutagen in Salmonella typhimurium strain TA100 in the presence of rat liver S9, whereas its isosteric isomer P[4,3-b]T is a nonmutagenic compound. In order to understand the mechanism underlying the differences in the mutagenic activity of P[3,4-b]T and P[4,3-b]T, we have investigated the metabolism of P[3,4-b]T, P[4,3-b]T, and their carbon analogue B[c]P by rat liver microsomes. The liver microsomes from rats treated with Aroclor 1254 metabolized P[3,4-b]T, P[3,4-b]T, and B[c]P at a rate nearly 7- to 9-fold greater than of the control liver microsomes. High-performance liquid chromatography (HPLC) analysis of the metabolites formed showed that B[c]P was metabolized almost exclusively to its dihydrodiols which comprised predominantly K-region diol as noted in the previous studies. Our preliminary studies on the metabolism of P[3,4-b]T, P[4,3-b]T and B[c]P by liver microsomes from control and Aroclor 1254-treated rats have shown a significant reduction in the formation of 6,7-diol (K-region diol) and 8,9-diol (diol with a bay-region double bond) of the two thia-PAHs compared to the formation of analogous 5,6-diol (K-region diol) and 3,4-diol (diol with a bay-region double bond) from B[c]P. Both P[3,4-b]T and P[4,3b]T produced a major, relatively nonpolar metabolite(s) (80–96% of total metabolites). These studies indicate that the highly mutagenic P[3,4-b]T is not metabolized to dihydrodiol with a bay-region double bond to any greater extent than the weakly or nonmutagenic B[c]P or P[4,3-b]T, suggesting that the metabolite(s) other than P[3,4-b]T8,9-diol is likely to be involved in the mutagenicity of P[3,4-b]T.     

A facile synthesis of some novel fused [1,2,4]triazolo[3,4-b][1,3,4]thiadiazol derivatives

A series of novel 3-[6-(4-substituted phenyl)-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-3-ylmethyl]-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidin-4(3H)-one derivatives (7a–7h) have been synthesized from 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (1) through a multi-step reaction sequence. The key intermediate (6) on condensation with various substituted aromatic carboxylic acids in the presence of phosphorus oxychloride afforded the series of title compounds (7a–7h). The structures of all newly synthesized compounds were established on the basis of their IR, ¹H-NMR, ¹³C-NMR and liquid chromatography mass spectrometry spectral data.     

薁并[2,1-b]吡啶的简便合成方法

以2-氨基-1-乙酰基薁-3-甲腈和β-二羰基化合物为原料,在1-甲基咪唑-3-丙基磺酸硫酸氢盐的作用下,一锅法合成了薁并[2,1-b]吡啶类衍生物。该反应收率良好、操作简单、条件温和。产物的结构通过红外光谱、核磁共振谱和元素分析证实。     

Reactions with 5,6-Diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones and 6,7-Diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one

2-Methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-one 5 and 6,7-diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one 6 are prepared from 4,5-diphenyl-2-mercapto-imidazole 1 . Compounds 5 and 6 react with amines or hydrazines to give the 2-(4,5-diphenyl-imidazol-2-ylthio)acet(or propan) amides (hydrazides) 7a – g and the 3-(4,5-diphenyl-imidazol-2 ylthio) propanamides(hydrazides) 8a – e , respectively. The hydrazides 7a, 7b and 8a are condensed with aromatic aldehydes to the hydrazones 9a – h and 10a – d . Compound 5 couples with aryldiazonium salts to give 2-arylazo-2-methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones 11a – d .     

Reaction of alkyl isocyanides and dialkyl acetylenedicarboxylates in the presence of 5,5-diaryl thiohydantoins. Synthesis of functionalized imidazo[2,1-b][1,3]thiazines

The reaction of stoichiometric amounts of dialkyl acetylenedicarboxylates with alkyl isocyanides in the presence of 5,5-diaryl thiohydantoins afforded imidazo[2,1-b][1,3]thiazines in good overall yields.     

Reactions of hydrazonoyl halides 44 [1]: synthesis of some new 1,3,4-thiadiazolines, 1,3,4-selenadiazolines and triazolino[4,3- a ]pyrimidines

1,3,4-Thiadiazolines, 1,3,4-selenadiazolines and triazolino[4,3-a]pyrimidines have been synthesized from 3-aza-[2,4-dimethyl(1,3-thiazol-5-yl)-2-bromo-3-substituted-amino]prop-2-en-1-ones with potassium thiocyanate, potassium selenocyanate, alkyl carbodithioates and 6-methyl-2-methylthio-4-substituted 3,4-dihydropyrimidine-5-carboxylates. Structures of the newly synthesized compounds have been established by elemental analysis, spectral data and alternative synthesis whenever possible. Some of products have been tested towards bacteria.     

Two-component,one-pot synthesis of pyrimido[1,2-b] [1,2,4,5]tetrazines

Derivatives containing the cyclohepta4′,5′thieno[2′,3′:4,5]pyrimido[1,2-b][1,2,4,5]-tetrazin-6-one system were prepared from the reaction of 3-amino-2-thioxo-1,2,3,5,6,7,8,9-octahydro-4H-cyclohepta[4,5]thieno[2,3-d]pyrimidin-4-one (5) or its 2-methylthio derivative 6 with hydrazonoyl chlorides 9. The mechanism of the studied reactions has been discussed and the biological activity of the isolated products has been evaluated.