Synthesis and antibacterial activity of 4-benzoyl-1-(4-carboxy-phenyl)-5-phenyl-1H-pyrazole-3-carboxylic acid and derivatives

A new 1H-pyrazole-3-carboxylic acid 2, along with hydrazono-pyridazinone 3, a by-product, and its derivatives 4–7 were synthesized and the structures confirmed by infrared (IR) and ¹H and ¹³C nuclear magnetic resonance (NMR) data. These new compounds were evaluated for their antibacterial activities against Gram-positive and Gram-negative bacteria using the tube dilution method. The minimal inhibitory concentrations (MICs) experiments revealed that most compounds exerted inhibitor effects against Klebsiella pneumonia, Escherichia coli, Bacillus subtilus, and Xanthomonas compestris test microorganisms. Moreover, the results showed that the pyrazolo[3,4-d]pyridazine compounds were the best compounds of the series, exhibiting antibacterial activity against both Gram-positive and Gram-negative bacteria.     

Synthesis, antimicrobial, analgesic activity, and molecular docking studies of novel 1-(5,7-dichloro-1,3-benzoxazol-2-yl)-3-phenyl-1H-pyrazole-4-carbaldehyde derivatives

Condensation of 5,7-dichloro-2-hydrazino-1,3-benzoxazole 3 with different aromatic acetophenones in methanol using catalytic amount of glacial acetic acid afforded the corresponding 1-phenylethanone(5,7-dichloro-1,3-benzoxazol-2-yl)hydrazones 5a–e in good yield. The compounds 5a–e, when subjected to Vilsmeier–Haack reaction with POCl₃ in DMF yielded (5,7-dichloro-1,3-benzoxazol-2-yl)-3-phenyl-1H-pyrazole-4-carbaldehyde derivatives 6a–e. The structural assignments of the compounds 6a–e are based on their spectral data and elemental analysis. The obtained compounds were tested for antimicrobial and analgesic activities, and subjected to molecular docking studies with respect to antimicrobial activity. The compound 6b showed pronounced antimicrobial and analgesic activity and exhibited an interesting binding profile with very high receptor affinity.     

Synthesis and antibacterial activity of 4-benzoyl-1-methyl-5-phenyl-1H-pyrazole-3-carboxylic acid and derivatives

Some new 1H-pyrazole-3-carboxylic acid and pyridazinone derivatives were synthesized and evaluated for their antibacterial activities against Bacillus cereus ATCC 7064, Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 4230 and Pseudomonas putida using tube dilution method. The minimal inhibitory concentrations (MICs) experiments revealed that all chemical compounds showed inhibitor effects on the growth of the test microorganisms. Moreover, the results of this research showed that the compound named as 5c was the best compound in the series, exhibiting antibacterial activity against both Gram-positive and Gram-negative bacteria.     

2-(3-氰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯的合成

目的优化非布司他关键中间体2-(3-氰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(4)的合成方法。方法采用"一勺烩"方法,以4-羟基苯甲腈为起始原料,首先与硫氢化钠和无水氯化镁在N,N-二甲基甲酰胺中反应,所得中间体不经分离,直接加入2-氯乙酰乙酸乙酯进行环合反应,得到2-(4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(2);然后通过六亚甲基四胺/三氟乙酸进行Duff反应,得到2-(3-甲酰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(3);再经盐酸羟胺/甲酸/甲酸钠体系脱水得到目标化合物。结果经四步反应合成非布司他关键中间体4,总收率为22.6%,其结构经核磁共振氢谱、质谱确证。结论改进后的工艺终产品无需柱色谱纯化,适合工业化生产。     

Synthesis and antimicrobial properties of N-substituted derivatives of (E)-4-azachalcones.

Syntheses of 11 new N-bromoalkyl substituted bromides of (E)-4-azachalcone and N-o-(m- and p-) halobenzyl substituted halides of (E)-3'-hydroxy-4-azachalcone of antimicrobial activity are reported. Compounds 3d, 3e, 6b, 6c, and 6e reveal good antimicrobial activity against Staphylococcus aureus and Enterococcus faecalis as well as moderate activity against Escherichia coli and Klebsiella pneumoniae.     

Synthesis of ester and amide derivatives of 1-phenyl-3-(thiophen-3-yl)-1H-pyrazole-4-carboxylic acid and study of their anticancer activity

A series of novel thiophene containing 1,3-diarylpyrazole derivatives were synthesized and the structures were determined by IR, ¹H-NMR, and HRMS analysis. The anticancer activity of the title compounds against MCF7, MDA-MB-231, HeLa, Raji, and HL60 human cancer cells growth were investigated by MTT assay. Interestingly, Raji and HL60 cells exhibited more sensitivity to synthesized compounds. (4-Benzyl-piperidin-1-yl)-(1-phenyl-3-thiophen-3-yl-1H-pyrazol-4-yl)-methanone (4c) possessed the highest growth inhibitory effect on Raji and HL60 cancer cells (GI₅₀ 25.2 ± 3.2 and 28.3 ± 1.53 μM, respectively). Compound 4f, 4-trifluoromethylphenyl piperazine at the amide part, also showed potent activity on Raji and HL60 cancer cell lines with a GI₅₀ value of 32.0 ± 1.27 and 36.7 ± 2.15 μM, respectively. Physicochemical properties of the synthesized compounds were evaluated in silico, and it was found that all compounds should present good passive oral absorption. All synthesized compounds demonstrated good drug-likeness values. The data suggested that these compounds might be promising for further development.     

Synthesis and biological activity of ethyl 2-(substituted benzylthio)-4-(3'-(ethoxycarbonyl)biphenyl-4-yl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate derivatives

In the present study, a new series of ethyl 2-(substituted benzylthio)-4-(3'-(ethoxycarbonyl)-biphenyl-4-yl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate derivatives was synthesized. The newly synthesized compounds were characterized by (1) H-NMR, mass and C, H, N analyses. All newly synthesized compounds were screened for their antibacterial (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes and Klebsiella pneumoniae) and antifungal (Aspergillus flavus, Aspergillus fumigatus, Candida albicans, Penicillium marneffei and Trichophyton mentagrophytes) activity. The results revealed that all synthesized compounds have a significant biological activity against the tested microorganisms. Compounds 8a, 8b, 8c, 8e, 8f, 8i, and 8j exhibited good antimicrobial activity.     

Synthesis and antimicrobial activity of some (3-phenyl-5-(1-phenyl-3-aryl-1H-pyrazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)(pyridin-4-yl)methanones: new derivatives of 1,3,5-trisubstituted pyrazolines

A series of (3-phenyl-5-(1-phenyl-3-aryl-1H-pyrazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)(pyridin-4-yl)methanones was synthesized by condensing suitably substituted chalcones, i.e., 3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)-1-phenylprop-2-en-1-ones, and isoniazid in acetic acid. The structure of newly synthesized compounds has been established on the basis of analytical and spectral data. The new compounds were screened for antimicrobial activity and most of them showed good activity comparable with that of standard drugs ciprofloxacin and fluconazole. Compounds containing methoxy group showed high antimicrobial activity.     

2-(5-甲基-2-苯基-4-(口恶)唑)-乙醇的合成

以丙酰乙酸乙酯为起始原料,先溴化得到4-溴丙酰乙酸乙酯,再在甲苯中与苯甲酰胺回流环合得到2-(5-甲基-2-苯基-4-(口恶)唑)-乙酸乙酯,最后经氢化铝锂还原,得到目标杂环中间体2-(5-甲基-2-苯基-4-(口恶)唑)-乙醇.该合成方法反应步骤少,原料便宜,目标物的总收率为67.3%.     

Synthesis,antitumor, and antimicrobial activity of N-substituted nitrofurylvinyl(butadienyl)-4-amino(hydrazino)quinolines

Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 23, No. 10, pp. 1226–1229, October, 1989.     

(2R,4R)-4-甲基-2-哌啶甲酸乙酯的合成工艺改进

目的 优化(2R,4R)-4-甲基-2-哌啶甲酸乙酯的合成工艺.方法 以S-(-)-α-甲基苄胺为原料,与乙醛酸乙酯反应得到[(S)-1-苯乙基亚胺基]乙酸乙酯,与异戊二烯进行环合后,再经不对称氢化和脱保护反应制得(2R,4R)-4-甲基-2-哌啶甲酸乙酯.结果 总收率从17.0％提高至47.6％.结论 本工艺可有效地降低生产成本.     

5-羟基-1H-吲哚-3-羧酸乙酯类化合物的合成及其抗流感病毒活性

目的设计合成5-羟基-1H-吲哚-3-羧酸乙酯类化合物,评价其抗流感病毒和抗呼吸道合胞病毒活性.方法经IR、1H-NMR和MS确证目标物结构,并经体外抗病毒试验进行活性筛选.结果与结论合成了9个5-羟基-1H-吲哚-3-羧酸乙酯类化合物,初步活性试验表明,具有一定的抑制流感病毒和呼吸道合胞病毒作用,其中,化合物Ⅷ1、Ⅷ2、Ⅷ5的抗病毒活性与利巴韦林和阿比朵尔相当.     

新型7-苯甲酰基中氮茚-1-羧酸乙酯类化合物的合成及HIV-1病毒感染因子抑制活性研究

目的设计合成7-苯甲酰基中氮茚-1-羧酸乙酯类化合物,并对其抗HIV-1活性进行初步研究。方法以异烟酸、溴乙酸苄酯、丙炔酸乙酯为原料,经取代、Friedel-Crafts反应、1,3-偶极环加成反应、水解、缩合得到目标化合物;采用荧光筛选方法对目标化合物抗HIV-1病毒感染因子(viral infectivity factor,VIF)活性进行评价。结果共合成30个未经文献报道的新化合物,其结构经1H-NMR、13C-NMR、HRMS确证;活性结果表明,化合物30、31、36、37等4个化合物抗HIV-1活性与先导化合物相当。结论 7-苯甲酰基中氮茚-1-羧酸乙酯类化合物作为HIV-1 VIF复合物抑制剂,中氮茚环与取代芳环之间含3～4个原子长度为保持活性所必须,进一步的构效关系值得继续研究。     

Synthesis and antimicrobial activity of 5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)thiazolidine-2,4-diones

A series of 5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)thiazolidine-2,4-diones was synthesized by Knoevenagel condensation of various 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes (1a–h) with thiazolidine-2,4-dione (2) in ethanol in the presence of piperidine. All compounds were screened for their in vitro antibacterial (Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli) activity and compared with the commercially available antibiotic, ciprofloxacin. All compounds showed good activity against gram-positive bacteria, however, none of the compounds were found to be effective against gram-negative bacteria. Compound 3g was found to be most potent member among all the compounds showing MIC of 16?μg/ml against S. aureus and 32?μg/ml against B. subtilis. All the synthesized compounds were also tested for their in vitro antifungal (Aspergillus niger and A. flavus) activity and compared with commercially available fluconazole. They showed excellent antifungal activity. Compounds 3b, 3e, 3f and 3g were active against both fungi showing more than 60% inhibition. Compound 3e was found to be superior to the reference drug.     

Synthesis of new 3-aryl-4-(3-aryl-4,5-dihydro-1H-pyrazol-5-yl)-1-phenyl-1H-pyrazole derivatives as potential antimicrobial agents

New (E)-1-aryl-3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)prop-2-en-1-ones 6 (pyrazolic chalcones) were synthesized from Claisen–Schmidt reaction of 3-aryl-1-phenylpyrazol-4-carboxaldehydes 4 with several acetophenone derivatives 5. Subsequently, the cyclocondensation reaction of chalcones 6 with phenylhydrazine in acetic acid medium afforded the new 3-aryl-4-(3-aryl-4,5-dihydro-1H-pyrazol-5-yl)-1-phenyl-1H-pyrazoles 7. The synthesized compounds were characterized by spectral studies and evaluated for their in vitro antibacterial activity against three pathogenic bacterial strains, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and in vitro antifungal activity against three pathogenic fungal strains Aspergillus flavus, Chrysosporium keratinophilum, and Candida albicans.     

Antifungal activity of novel 5-carbonyl derivatives of 3-phenyl-3-(1H-imidazol-1-ylmethyl)-2-methylisoxazolidines

The synthesis and antifungal activity of a series of novel 5-carbonyl derivatives of 3-phenyl-3-(1H-imidazol-1-ylmethyl)-2-methylisoxazolidines (4) are discussed. The preparation of the title compounds involved a 1,3-dipolar cycloaddition reaction of alpha-substituted ketonitrones with either acrylic esters, acrylamide or methyl vinyl ketone to furnish cis/trans-diastereomeric mixtures of the desired 5-carbonyl isoxazolidines 4. The anifungal activity was evaluated in vitro in solid agar cultures. Some of the compounds tested exerted moderate to potent activity against a wide variety of dermatophytes and yeast and systemic fungi.     

Synthesis and antimicrobial activity of some new N-substituted quinoline derivatives of 1H-pyrazole

A new series of 32 derivatives of 4-pyrazolyl-N-(hetero)arylquinoline 5a-p and 6a-p were synthesized by a one-pot base-catalyzed cyclocondensation reaction of 1-phenyl-3-(hetero)aryl-pyrazole-4-carbaldehyde 1a-h, malononitrile 2, and 3-(hetero)aryl-5,5-disubstitutedcyclohex-2-enone 3a-b or 4a-b, respectively. All the synthesized compounds were characterized by elemental analysis, FT-IR, (1) H-NMR, and (13) C-NMR spectral data. All the synthesized compounds were screened, against six bacterial pathogens, namely Bacillus subtilis, Clostridium tetani, Streptococcus pneumoniae, Salmonella typhi, Vibrio cholerae, Escherichia coli, and antifungal activity, against two fungal pathogens Aspergillus fumigatus and Candida albicans, using broth microdilution MIC method. Some of the compounds were found to be more or equipotent against most of the employed strains than commercially available drugs as evident from the screening data.     

Synthesis and pharmacological activity of 1-[2-(3,4-dimethoxyphenyl)ethyl]-4-hydroxypiperidine derivatives

Translated from Khimiko-farmatsevitcheskii Zhurnal, Vol. 25, No. 4, pp. 22–24, April, 1991.