(S)-5-(氮杂环亚甲基)-3-(3-氟-4-吗啉-4-基-苯基)噁唑烷-2-酮衍生物的合成及抗菌活性

目的研究具有抗菌作用的噁唑烷酮衍生物的构效关系。方法由(S)-[3-(3-氟-4-吗啉-4-基-苯基)噁唑烷-2-酮-5-基]-甲醇甲磺酸酯和仲胺的取代反应合成了7个(S)-5-氮杂环亚甲基-3-(3-氟-4-吗啉-4-基-苯基)噁唑烷-2-酮衍生物,其结构通过1HNMR和元素分析或质谱确证。结果所合成的7个化合物对所测的20株细菌均没有明显的体外抗菌活性。结论用氮杂环亚甲基取代吗啉噁酮的5位乙酰胺甲基降低化合物的抗菌活性。     

(S)-5-乙酰胺甲基-3-［(4-取代胺甲基)苯基］-2-噁唑烷酮衍生物的合成及抗菌活性

目的研究噁唑烷酮类衍生物的合成及抗菌活性。方法以4-甲基-3-卤代苯胺为原料，经氯甲酸苄酯酰化、与(R)-丁酸缩水甘油酯环合、甲磺酰化、叠氮化、叠氮还原成胺、胺基乙酰化、苄位溴化得到中间体取代溴苄VIIIa和VIIIb。VIIIa和VIIIb与胺类化合物包括脂肪胺、芳香胺发生取代反应生成IXa和IXb；测定目标化合物的体外抗菌活性。结果设计、合成了51个新化合物，其结构经¹H NMR、元素分析或MS确证。并测定了它们的比旋光度等理化常数。化合物VIIb，IXa1，IXa2，IXa7，IXb1，IXb3，IXb10，IXb16和IXb23对G⁺菌有一定的活性，但不如对照品吗啉噁酮和诺氟沙星。结论在吗啉噁酮结构中苯环4位和吗啉基之间插入亚甲基，不能提高化合物的抗菌活性。     

3-(4-氨基-5-甲基-均三唑-3-硫基)-1-苯丙-1-酮-O-(5-取代苯基-［1,3,4］噁二唑-2-甲基)肟的合成及抗菌活性

目的研究氨基杂环肟类化合物的合成方法和抗菌活性。方法用4-氨基-3-甲基-5-巯基-［1,2,4］三唑与β-氯苯丙酮缩合、肟化、醚化得3-(4-氨基-5-甲基-均三唑-3-硫基)-1-苯丙-1-酮-O-(5-取代苯基-［1,3,4］噁二唑-2-甲基)肟醚目标化合物。用二倍试管稀释方法研究了目标化合物的体外抑菌活性。结果合成了12个新化合物，其结构经MS，IR，¹H NMR和元素分析确证。10个目标化合物在体外有一定的抗菌活性。结论该类杂环化合物有待进一步的结构优化研究。     

3-(5-取代苯基-［1,3,4］恶二唑-2-亚甲硫基)-5-吡啶-3-基-［1,2,4］三唑-4-胺的合成及抗菌活性

目的研究多杂环化合物的合成方法和抗菌活性。方法用4-氨基-3-吡啶-3-基-［1,2,4］三唑-5-硫醇与5-取代苯基-2-氯甲基-［1,3,4］恶二唑缩合得相应的目标胺类化合物。用平皿试验法，研究了目标化合物的体外抑菌活性。结果合成了12个新化合物，其结构经MS，IR，¹H NMR和元素分析确证。多数化合物在体外表现出较好的抑菌活性。结论含吡啶的恶二唑三唑多杂环化胺类化合物有可能成为新型结构的抗菌药物。     

3-(4-哌嗪-1-苯基)-6-取代-s-三唑并［3,4-b］［1,3,4］噻二唑盐酸盐的合成及抗菌活性

为了研究水溶性稠杂环化合物的合成方法及抗菌活性，本研究采用3-(4-氯苯基)-6-取代-s-三唑并［3,4-b］［1,3,4］噻二唑(2a～n)在相转移催化剂TBAI作用下与哌嗪发生亲核取代，再与盐酸成盐制备了3-(4-哌嗪-1-苯基)-6-取代-s-三唑［3,4-b］［1,3,4］噻二唑盐酸盐(3a～n)。用试管二倍稀释法研究了新化合物的体外抗菌活性。结果表明，合成的28个新化合物极性碱性哌嗪基的引入可提高化合物的抗菌活性。该类稠杂环化合物的结构有待进一步优化。     

3-氟-4-(2-芳基噻唑-4-基)苯基(噁)唑烷酮类化合物的合成及抗菌活性

目的设计并合成3-氟-4-（2-芳基噻唑-4-基）苯基噁唑烷酮类化合物，初步评价其体外抗菌活性。方法 以（R）-环氧氯丙烷和间氟苯基异氰酸酯为起始原料，通过新的合成路线制备了目标化合物；采用微量液体稀释法，测定目标化合物的体外抗菌活性。结果与结论 合成了14个新化合物。其结构经^1H-NMR、MS确认，10个化合物显示出不同程度的抗菌活性，化合物IXc和Xc的活性较好，有进一步研究的价值。     

2-(3-吡啶)-5-{［(5-芳基-1,3,4-二唑-2-基)亚甲基］硫代}-1,3,4-二唑的合成及抗菌活性

目的研究多杂环化合物的合成方法和抗菌活性。方法用［(5-吡啶-3-基-1,3,4-二唑-2-基)硫代］乙酸与相应的芳酰肼缩合,得到相应的目标化合物。用试管稀释法,研究目标化合物的体外抑菌活性。结果合成了16个新化合物,其结构经MS,IR,₁HNMR和元素分析确证。其中多数化合物在体外表现出较好的抑菌活性。结论 含吡啶的双二唑杂环化合物有可能成为新型结构的抗菌药物。     

咪唑并［2,1-b］［1,3,4］噻二唑及杂环氨曼尼希碱盐酸盐的合成及抗菌活性

为了进一步优化由噻二唑核稠合的水溶性稠杂环化合物的合成方法及抗菌活性，本文用2-(4-甲氧苯基)-5-氨基-1,3,4-噻二唑(2)与α-氯代-4-氯苯乙酮(3)缩合得6-(4-氯苯基)-2-(4-甲氧苯基)-咪唑并［2,1-b］［1,3,4］噻二唑(4)，4与取代哌嗪发生亲核取代反应得到6-(4-取代哌嗪-1-苯基)-2-(4-甲氧苯基)-咪唑并［2,1-b］-［1,3,4］噻二唑(5)，5与杂环氨进行曼尼希反应并与盐酸成盐得目标化合物6-(4-取代哌嗪-1-苯基)-2-(4-甲氧苯基)-5-杂环氨基甲基-咪唑并［2,1-b］［1,3,4］噻二唑盐酸盐(1)。用试管二倍稀释法评价了15个新化合物的体外抗菌活性，结果表明，随着极性基团的引入，抗菌活性显著提高，提示该类化合物的结构修饰值得进一步研究。     

新型噁唑烷酮-吲哚羧酸酯杂合物的合成及抗菌活性

摘 要：目的 设计并合成一类新型的4-哌嗪苯基噁唑烷酮-吲哚羧酸酯杂合物，初步评价其体外抗菌活性。方法 以(S)-N-[[3-[3-氟-4-(哌嗪-1-基)苯基]-2-氧代-5-噁唑烷酮基]甲基]乙酰胺为起始原料，经过2步反应合成目标化合物；采用微量液体稀释法，测定目标化合物的体外抗菌活性。结果与结论 合成了14个新化合物，其结构经1H-NMR和MS确认，7个化合物显示出不同程度的抗菌活性，化合物3a和4b的活性突出，可进行深入研究。     

3--氟4-(2-芳基噻-唑4-基)苯基唑烷酮类化合物的合成及抗菌活性

目的设计并合成3--氟4-(2-芳基噻-唑4-基)苯基唑烷酮类化合物,初步评价其体外抗菌活性。方法以(R)-环氧氯丙烷和间氟苯基异氰酸酯为起始原料,通过新的合成路线制备了目标化合物;采用微量液体稀释法,测定目标化合物的体外抗菌活性。结果与结论合成了14个新化合物,其结构经1H-NMR、MS确认,10个化合物显示出不同程度的抗菌活性,化合物IXc和Xc的活性较好,有进一步研究的价值。     

Synthesis and antimicrobial activity of some 5-[2-(morpholin-4-yl)acetamido] and/or 5-[2-(4-substituted piperazin-1-yl)acetamido]-2-(p-substituted phenyl)benzoxazoles

In this study, a series of twelve novel 5-[2-(morpholin-4-yl)acetamido] and/or 5-[2-(4-substituted pip-erazine-1-yl)acetamido]-2-(p-substituted phenyl]benzoxazole derivatives have been synthesized and their structures were confirmed by IR, (1)H NMR, and mass spectral data. These compounds were prepared by reacting 5-(2-chloroacetamido)-2-(4-p-substituted-phenyl)benzoxazoles, which were obtained by using 5-amino-2-[p-substituted-phenyl]benzoxazoles with chloroacetyl chloride, in the presence of morpholine or 1-substituted piperazines. All synthesized compounds 3-14 were tested by using the method of twofold serial dilution technique for in vitro activities against certain strains of Gram-positive, Gram-negative bacteria as well as the yeasts Candida albicans, Candida krusei, and Candida glabrata in comparison with standard drugs. Microbiological results showed that the newly synthesized compounds possessed a broad spectrum of activity, showing MIC values of 3.12-50 mug/mL against the Candida species.     

Synthesis and antituberculosis activity of new N-phenyl-N'-[4-(5-alkyl/arylamino-1,3,4-thiadiazole-2-yl)phenyl]thioureas

In this study, eight original N-phenyl-N'-[4-(5-alkyl/arylamino-1,3,4-thiadiazole-2-yl)phenyl]thiourea derivatives were synthesized and tested for antituberculosis activity. Antituberculosis activities of the synthesized compounds were screened in vitro using BACTEC 460 Radiometric System against Mycobacterium tuberculosis H37Rv at 6.25 microg/ml. The highest inhibition observed with the synthesized compounds is 67% for N-phenyl-N'-[4-(5-cyclohexylamino-1,3,4-thiadiazole-2-yl)phenyl]thiourea.     

Synthesis and structure-activity relationships of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]cephalosporin derivatives. V. Synthesis and antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-cephalosporin derivates and related compounds

In order to improve the antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]-cephalosporins new derivatives having a methoxyimino moiety in the 7-acyl side chain and related compounds were synthesized. Of these, 7 beta-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyiminoacetamido]-cephalosporins were found to possess excellent activity against a variety of Gram-positive and Gram-negative bacteria including beta-lactamase-producing strains. An extensive study of structure-activity relationships led to the selection of 7 beta-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyiminoacetamido]-3-[(1-methyl-1H-tetrazol-5-yl) thiomethyl]-ceph-3-em-4-carboxylic acid, SCE-1365, for further biological and clinical evaluation.     

Antibacterial, antifungal and anticonvulsant evaluation of novel newly synthesized 1-[2-(1H-tetrazol-5-yl)ethyl]-1H-benzo[d][1,2,3]triazoles

Several novel 1-[2-(1H-tetrazol-5-yl) ethyl]-1H-benzo[d][1,2,3]triazoles (3a-h) have been synthesized by the condensation of 1-[2-(1H-tetrazol-5-yl)-ethyl]-1H-benzotriazole (2) and appropriate acid chlorides. 1-[2-(1H-tetrazol-5-yl)-ethyl]-1H-benzotriazole (2) was synthesized by reacting 3-(1H-benzo[d][1,2,3]triazol-1-yl)propanenitrile with sodium azide and ammonium chloride in the presence of dimethylformamide. The synthesized compounds were characterized by IR and PMR analysis. The titled compounds were evaluated for their in-vitro antibacterial and antifungal activity by the cup plate method and anticonvulsant activity evaluated by the maximal electroshock induced convulsion method in mice. All synthesized compounds exhibited moderate antibacterial activity against Bacillus subtilis and moderate antifungal activity against Candida albicans. Compounds 5-(2-(1H-benzo[d][1,2,3]triazo-1-yl)ethyl)-1H-tetrazol-1-yl)(4-aminophenyl)methanone 3d and 5-(2-(1 H-benzo[d][1,2,3]triazo-1-yl)ethyl)-1H-tetrazol-1-yl)(2-aminophenyl)methanone 3e elicited excellent anticonvulsant activity.     

Studies on condensed-heterocyclic azolium cephalosporins. III. Synthesis and antibacterial activity of 7 beta-[2-(2-amino-5-substituted-thiazol-4-yl)-2 (Z)-alkoxyiminoacetamido]-3-(condensed-heterocyclic azolium)methyl-3-cephem-4- carboxylates.

As a part of our research on the synthesis of cephalosporins bearing condensed-heterocyclic azolium groups at the 3 position in the cephalosporin nucleus, we describe herein the synthesis of 7 beta-[2-(2-amino-5-halogeno-, methylthio-, methylsulfinyl-, methylsulfonyl- and sulfothiazol-4-yl)-2(Z)-alkoxyiminoacetamido] cephalosporins and their antibacterial activity. Among the compounds prepared, 7 beta-[2-(2-amino-5-chlorothiazol-4-yl)-2(Z)- methoxyiminoacetamido]-3-(imidazo[1,5-a]-pyridinium-1-yl)methyl-3-cephem -4-carboxylate (14) showed good antibacterial activity against both Staphylococcus aureus including methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, whereas the antibacterial activity against other Gram-negative bacteria was a slightly lower than that of 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3-(im ida zo [1,2-a]pyridinium (I-1) and imidazo[1,5-a]pyridinium (I-4)-1-yl)methyl-3-cephem-4-carboxylates.     

Studies on condensed-heterocyclic azolium cephalosporins. I. Synthesis and antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)- alkoxyiminoacetamido]-3-(imidazo[1,2-a]pyridinium-1-yl)methyl-3- cephem-4-carboxylates.

In our study of the structure-activity relationships of cephalosporins bearing quaternary ammonium groups at the 3 position, we postulated that delocalization of the azolium positive charge would lead to an expanded antibacterial spectrum and increased activity. Since quaternization of condensed-heterocyclic compounds such as imidazo[1,2-a]pyridine gives positive charge delocalization, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-alkoxyiminoacetamido] cephalosporin derivatives (1-53) bearing various (imidazo[1,2-a]pyridinium-1-yl)methyl moieties at the 3 position were prepared and their antibacterial activity was determined. As expected, these cephalosporins exhibited potent activity against both Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa. These results imply that imidazo[1,2-a]pyridine is a quite useful substituent for improving antibacterial activity and spectrum. The structure-activity studies revealed that a favorable substituent on the imidazo[1,2-a]pyridine is the cyano radical at the 6 position of the ring, and ethoxyimino or 1-carboxy-1-methylethoxyimino groups are suitable for the alkoxyimino substituent. Among the cephalosporins tested, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)- ethoxyiminoacetamido]-3-(6-cyanoimidazo[1,2-a]pyridinium -1-yl)methyl-3-cephem-4-carboxylate (45) and 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-(1- carboxy-1-methylethoxyiminoacetamido]-3-(6-cyanoimidazo[1,2- a] pyridinium-1-yl)methyl-3-cephem-4-carboxylate (49) showed good antibacterial activity.     

Synthesis and antibacterial activity of N-[5-chlorobenzylthio-1,3,4-thiadiazol-2-yl] piperazinyl quinolone derivatives

A series ofN-[5-(chlorobenzylthio)-1,3,4-thiadiazol-2-yl] piperazinyl quinolone derivatives (4a-1) have been synthesized by reaction of piperazinyl quinolones with 5-chloro-2-(chloroben-zylthio)-1,3,4-thiadiazoles. Their structures were confirmed by elemental analysis, IR and NMR spectra. The antibacterial activities of4a-1 against a variety of Gram-positive and Gram-negative bacteria were determined. Several compounds showed a good antibacterial activity against Gram-positive bacteria among which, compound 4e with a 2-chlorobenzylthio moiety in ciprofloxacin derivative, exhibited high activities againstStaphylococcus aureus andStaphylococcus epidermidis (MIC=0.06 μg/mL). The structure-activity relationship (SAR) study revealed that the position of chlorine atom on benzyl moiety would dramatically affect the antibacterial activities of the synthesized compounds.     

Synthesis and antimycobacterial activity of some N1-[1-[3-aryl-1-(pyridin-2-, 3-, or 4-yl)-3-oxo]propyl]-2- pyridinecarboxamidrazones

N1-[1-[3-aryl-1-(pyridin-2,3-, and 4-yl)-3-oxo[propyl]-2- pyridinecarboxamidrazone derivatives were synthesized and tested for their in vitro antimycobacterial activity. Some compounds showed interesting activity against a strain of Mycobacterium tuberculosis and a strain of Mycobacterium avium.     

A new cephalosporin. SCE-963: 7-[2-(2-aminothiazol-4-yl)-acetamido]-3-[[[1-(2-dimethylaminoethyl)-1h-tetrazol-5-yl]-thio]methyl]ceph-3-em-4-carboxylic acid. Chemistry and structure-activity relationships.

The synthesis and the in vitro and in vivo antimicrobial activities of a series of 7-[2-(2-aminothiazol-4-yl)acetamido]cephalosporins (1) having varied 3-substituents, such as methyl, hydroxymethyl, acetoxymethyl, pyridiniomethyl and heterocyclicthiomethyls, are described. The derivatives having five membered heterocyclicthiomethyls exhibited strong inhibitory activities against Gram-negative organisms including some strains of Escherichia coli and Proteus morganii which are insensitive to cefazolin and cephaloridine. Pronounced activities were noted with 7-[2-(2-aminothiazol-4-yl)-acetamido]-3-[[[1-(2-dimethylaminoethyl)-1H-tetrazol-5-yl]thio]methyl]ceph-3-em-4-carboxylic acid (1y; SCE-963).