Amide derivatives of [6-(5-methyl-3-phenylpyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acids as potential analgesic and anti-inflammatory compounds

In this study, amide derivatives of [6-(5-methyl-3-phenyl-pyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acid were synthesized and tested for their in vivo analgesic and anti-inflammatory activity by using the p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. The analgesic and anti-inflammatory activity of the compounds 6a, 6d, 6e, 6g, 6h and 6m were more potent than that of aspirin as an analgesic and indomethacin as an anti-inflammatory drug, respectively. The other derivatives generally resulted in comparable activity to reference compounds. Inhibitor activity of the active compounds on cyclooxygenase isoforms was also investigated by using in vitro human whole blood assay and found that these derivatives did not exert their analgesic and anti-inflammatory activities through COX inhibition and other mechanisms might be involved.     

Synthesis and antinociceptive activity of (5-chloro-2(3H)-benzothiazolon-3-yl)propanamide derivatives

Ten new (5-chloro-2(3H)-benzothiazolon-3-yl)propanamide derivatives have been synthesized. The compounds were tested for antinociceptive activity by tail clip, tail flick, hot plate and writhing test by using aspirin and dipyrone as standards. Among these compounds, 1-[3-(5-chloro-2(3H)-benzothiazolon-3-yl)-propanoyl]-4-(4-chlorophenyl)piperazine (11e) has been found to be significantly more active than the other compounds synthesized as well as the standards in all tests.     

N-substituted 3-(arylamino)-4,5-dihydro-2H-benz[g]indazol-2-yl acetamides with anti-inflammatory and analgesic activities

A series of substituted 3-(arylamino)-4,5-dihydro-2H-benz[g]indazol-2-yl acetamides was synthesized and tested in comparison with former analogues. The title compounds showed only weak antiarrhythmic properties but good anti-inflammatory and antinociceptive activity, particularly evident in the morpholino derivative.     

4-(5-chloro-2(3H)-benzoxazolon-3-yl) butanoic acid derivatives: synthesis, antinociceptive and anti-inflammatory properties

In this study, 4-(5-chloro-2(3H)-benzoxazolone-3-yl)butanoic acid and its ethyl ester as well as its ten new amide derivatives have been synthesized. Their structures have been elucidated by IR, (1)H-NMR spectra and elemental analysis. The compounds were screened for antinociceptive and anti-inflammatory activities. The highest antinociceptive and anti-inflammatory activities were exhibited by Compound 11 which has carboxylic acid structure. A various decrease in antinociceptive and anti-inflammatory activity was observed by amidation of the carboxylic acid moiety of this compound.     

Synthesis, physicochemical and anticonvulsant properties of new N-4-arylpiperazin-1-yl amides of (2-aza-1,3-dioxospiro[4.4]non-2-yl)- and [4.5]dec-2-yl)-propionic acid

In continuation of the search of new anticonvulsants, a series of N-4-arylpiperazin-1-yl 2-aza-1,3-dioxospiro[4.4]non-2-yl- (5-8) and [4.5]dec-2-yl- (9-15) propionamides, structurally related to the previously described N-4-arylpiperazin-1-yl amides of 2-aza-1,3-dioxospiro[4.5]dec-2-yl-acetic acid, were synthesized. The designed compounds 5-15 were prepared by condensation of the formerly obtained (2-aza-1,3-dioxospiro[4.5]dec-2-yl)- (3) and (2-aza-1,3-dioxo[4.4]non-2-yl)-(4) propionic acids with the appropriately substituted 4-arylpiperazines, in the presence of the N,N-carbonyldiimidazole (CDIM) reagent. All the compounds were tested for their anticonvulsant activity in the maximum electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure threshold tests. Several compounds 7-10, 13 and 14 revealed protection in the MES screening.     

Synthesis, Analgesic, and Anti-Inflammatory Activities of [6-(3,5-Dimethyl-4-Chloropyrazole-1-yl)-3(2H)-Pyridazinon-2-yl]Acetamides

A series of structurally diverse amide derivatives of [6-(3,5-dimethyl-4-chloro-pyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acid were prepared and tested for their in vivo analgesic and anti-inflammatory activity by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. The analgesic and anti-inflammatory activity of the compounds, 7c, 7d and 7k were found to be equipotent to aspirin (as an analgesic) and indometacin (as an anti-inflammatory drug), respectively. The other amide derivatives generally resulted in lower activity on comparision with reference compounds.     

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 antinociceptive activity of (1-benzyl-2(3H)-benzimidazolon- 3-yl) acetic acid derivatives

Eight (1-benzyl-2(3H)-benzimidazolon-3-yl)acetic acid derivatives have been synthesized and tested for antinociceptive activity in this study. All compounds but one, at the oral dose of 100 mg/kg were comparable with aspirin. Ethyl (1-benzyl-2(3H)-benzimidazolon-3-yl)acetate (3), 4-[(1-benzyl-2(3H)-benzimidazolon-3-yl)acetyl]morpholine (6a) and 1-[(1-benzyl-2(3H)-benzimidazolon-3-yl)acetyl]pyrrolidine (6b) have shown more potent antinociceptive activity than others.     

Synthesis of amide derivatives of [6-(3,5-dimethylpyrazol-1-yl)-3(2H)-pyridazinone-2-yl] acetic acid and their analgesic and anti-inflammatory properties

A series of structurally different amide derivatives of [6-(3,5-dimethylpyrazol-1-yl)-3(2H)-pyridazinone-2-yl]acetic acid were prepared and tested for their analgesic and anti-inflammatory activity in vivo by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. The analgesic and anti-inflammatory activity of the compounds 6a and 6b were equipotent, and 6m was more potent than acetyl salicylic acid (CAS 50-78-2) as an analgesic and indometacin (CAS 53-86-1) as an anti-inflammatory drug, respectively. The other amide derivatives and parent carboxylic acid molecule generally resulted in lower activity to reference compounds. Inhibitor activity of the active compounds on cyclooxygenase isoforms was also investigated by using in vitro COX inhibitor screening assay and found that these derivatives did not exert their analgesic and anti-inflammatory activities through COX inhibition and that other mechanisms might be involved.     

Synthesis and analgesic and anti-inflammatory activity of ethyl (6-substituted-3 (2H)-pyridazinone-2-yl)acetate derivatives

A number of 6-substituted-3(2H)-pyridazinones and the corresponding methyl (6-substituted-3(2H)-pyridazinone-2-yl)acetate derivatives carrying the arylpiperazinyl structure present in potent antinociceptive agents reported in the literature were synthesized. As part of a programme a series of diverse arylpiperazine derivatives of ethyl (6-substituted-3(2H)-pyridazinone-2-yl)acetate were prepared and tested for their in vivo analgesic and anti-inflammatory activity by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. Side effects of the compounds were examined on gastric mucosa. None of the compounds showed gastric ulcerogenic effect compared with reference non-steroidal anti-inflammatory drugs (NSAIDs). On the basis of available data, the structure-activity relationship in the series of ethyl (6-substituted-3(2H)-pyridazinone-2-yl)acetate derivatives was also discussed. When compared to parent 6-substituted-3(2H)-pyridazinones, the new ester derivatives, for example ethyl (6-4-[(2-fluoro)phenyl]piperazine-3(2H)-pyridazinone-2-yl)acetate exhibited better analgesic and anti-inflammatory activity and a lower ulcerogenic effect.     

Synthesis of 2-(4-substitutedbenzyl-[1,4]diazepan-1-yl)-n-(1-methyl-4,5-dihydro-[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamides as inotropic agents

In an attempt to search for more potent positive inotropic agents, a series of N-(4,5-dihydro-1-methyl-[1,2,4]triazolo[4,3-a]quinolin-7-yl)-2-(substitutedbenzyl-[1,4]diazepan-1-yl)acetamides were synthesized and evaluated for positive inotropic activity by measuring left atrium stroke volume in isolated rabbit heart preparations. Some of these derivatives exhibited favorable activity compared with the standard drug, milrinone, among which 2-(4-(4-methylbenzyl)-[1,4]-diazepan-1-yl)-N-(4,5-dihydro-1-methyl-[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamide (6m) was the most potent, increasing stroke volume by 8.38±0.16% (milrinone 2.45± 0.06%) at 3 x 10(-5) m. The chronotropic effects of those compounds having inotropic effects were also evaluated in this work.     

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.     

New 3-[4-(2,3-dihydro-14-benzodioxin-5-yl)piperazin-1-yl]-1-(5-substituted benzo[b]thiophen-3-yl)propanol derivatives with dual action at 5-HT(1A) serotonin receptors and serotonin transporter as a new class of antidepressants

Compounds derived from 2,3-dihydro-(1,4-benzodioxin-5-yl)piperazine and benzo[b]thiophene with different substituents in 5 position (H, F, NO2, NH2, CH3 and OH) have been synthesized in order to obtain new dual antidepressant drugs. The final compounds were evaluated for in vitro 5-HT(1A) receptor affinity and serotonin reuptake inhibition by radioligand assays. Compounds 1-(5-nitrobenzo[b]thiophen-3-yl)-3-[4-(2,3-dihydro-1,4-benzodioxin-5-yl)piperazin-1-yl]propan-1-ol (4c) (Ki = 6.8 for 5-HT(1A) receptor and Ki = 14 for 5-HT transporter) and 1-(5-hydroxybenzo[b]thiophen-3-yl)-3-[4-(2,3-dihydro-1,4-benzodioxin-5-yl)piperazin-1-yl] propan-1-ol (4f) (Ki = 6.2 for 5-HT(1A) receptor and Ki = 18.2 for 5-HT transporter) showed the best results for both activities.     

7-{4-［2-［2-取代-4-((5S)-5-乙酰胺甲基-2-氧代-噁唑烷-3-基)苯基］乙基］哌嗪-1-基}-氟喹诺酮类化合物的合成与抗菌活性

目的寻找新型的噁唑烷酮-氟喹诺酮类抗菌药物。方法设计合成了7-{4-［2-［2-取代-4-((5S)-5-乙酰胺甲基-2-氧代-噁唑烷-3-基)苯基］乙基］哌嗪-1-基}-氟喹诺酮类化合物，测定其体外抗菌活性。结果共合成20个目标化合物，经^{1H NMR和MS确证结构。目标化合物具有较好的体外抗菌活性，尤其是化合物22，对屎肠球菌的抑制活性分别是吗啉噁酮和诺氟沙星的16倍和64倍，对金葡菌的抑制活性为吗啉噁酮的4倍。结论某些带有氟喹诺酮结构片段的噁唑烷酮类化合物抗菌活性加强。}     

3H]N-[4-(3,4-dihydro-6,7-dimethoxyisoquinolin-2(1H)-yl)butyl]-2-methoxy-5-methylbenzamide: a novel sigma-2 receptor probe

N-[4-(3,4-dihydro-6,7-dimethoxyisoquinolin-2(1H)-yl)butyl]-2-methoxy-5-methyl-benzamide (RHM-1) and N-[2-(3,4-dihydro-6,7-dimethoxyisoquinolin-2(1H)-yl)ethyl]-2-methoxy-5-methylbenzamide (RHM-2), two conformationally flexible benzamide analogues, were radiolabeled with tritium (specific activity=80 Ci/mmol) and the binding of [3H]RHM-1 and [3H]RHM-2 to sigma-2 (sigma2) receptors was evaluated in vitro. [3H]RHM-1 was found to have a higher affinity for sigma2 receptors compared to [3H]RHM-2 and [3H]1,3-di-o-tolylguanidine ([3H]DTG). [3H]RHM-1 had a dissociation constant (Kd) of 0.66+/-0.12 nM in rat liver membrane homogenates, which was 30-fold higher than that of [3H]RHM-2 (Kd=19.48+/-0.51 nM). The lower affinity of [3H]RHM-2 can be attributed to its faster K(off) rate since both radioligands have similar K(on) rates. Competitive binding assays were also conducted using a panel of compounds with known affinity for sigma2 receptors. The pharmacologic profile of [3H]RHM-1 was in agreement with that of [3H]DTG. The results of this study indicate that [3H]RHM-1 is a useful ligand for studying sigma2 receptors in vitro.     

3,4-二氢吡咯[1,2-a]吡嗪-1-酮衍生物的合成及抗炎镇痛作用

目的研究(2H)-2-环己基-3,4-二氢吡咯[1,2-a]吡嗪-1-酮衍生物抗炎镇痛作用的构效关系。方法以2-吡咯甲酸甲酯为原料,经取代、环合,制备(2H)-2-环己基-3,4-二氢吡咯[1,2-a]吡嗪-1-酮(3);通过Friedel-Crafts酰基化反应,制得其6-酰基衍生物4a~4j。用小鼠测试了所合成化合物的抗炎和镇痛活性。结果与结论合成了10个未见文献报道的新化合物4a~4j,其结构经MS1、H-NMR分析确证。抗炎镇痛试验表明,有些化合物具有明显的抗炎和/或镇痛作用,其中化合物4d的活性与对照药布洛芬相当。     

Synthesis and characterization of (Z)-N-(1-[2-{3-[(dimethylamino)methyl)]-2-methoxyphenyl}-5-(pyridin-4-yl)-1,3,4-oxadiazol-3(2H)-yl]ethylidene) benzenamine derivatives as potent antifungal agents

In the present study, a series of (Z)-N-(1-[2-{3-[(dimethylamino)methyl)]-2-methoxyphenyl}-5-(pyridin-4-yl)-1,3,4-oxadiazol-3(2H)-yl]ethylidene)benzenamine derivatives have been synthesized and characterized by IR, 1H NMR and 13C NMR spectra. All the synthesized compounds were evaluated for their antifungal activity and were compared with the standard drug, clotrimazole. The compounds demonstrated excellent to weak antifungal activity. Among the synthesized derivatives, 4f and 4h showed significant activity and 4c exhibited moderate activity against Candida albicans, Candida tropicalis and Aspergillus niger as compared with the standard antifungal agent - clotrimazole. The minimum inhibitory concentration of the compounds was in the range of 1.62-25 microg/mL against fungi. Furthermore, the substitution of chloro, nitro and methoxy groups at para position of benzene moiety play an important role in enhancing the antifungal activity of this class of compounds.     

Synthesis and antimicrobial activity of [2-[2-(N,N-disubstituted thiocarbamoyl-sulfanyl)-acylamino] thiazol-4-yl]acetic acid ethyl esters

[2-[2-(N, N-Disubstituted thiocarbamoyl-sulfanyl)acylamino ]thiazol-4-yl]acetic acid ethyl esters (3a-x) were synthesized by the reaction of potassium salts of N, N-disubstituted dithiocarbamoic acids with [2-(2-chloroalkanoyl)amino-thiazol-4-yl]acetic acid ethyl esters. The structures of the synthesized compounds were confirmed by elemental analyses, UV, IR, (1)H-NMR, and EI mass spectral data. The antimicrobial activities of all the compounds were investigated by microbroth dilution technique using Mueller-Hinton broth and Mueller-Hinton agar. In this study, Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa AT CC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis ATCC 14153 and Candida albicans ATCC10231 were used as test microorganisms. Among the tested compounds 3a, d, e, f, h, k, w activity against S. epidermidis ATCC 12228 (MIC: 156 mg/L, 78 mg/L, 62.5 mg/L, 78 mg/L, 62.5 mg/L, 312 mg/L, 250 mg/L, respectively), compound 3d had some activity against S. aureus ATCC 6538 (MIC: 156 mg/L) and C. albicans ATCC 10231(MIC: 156 mg/L). Compounds 3l, 3x also evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. The preliminary results indicated that all of the tested compounds were inactive against the test organism.     

Microwave-assisted solvent-free synthesis of 3-[(4-substituted piperazin-1-yl)alkyl] imidazo[2,1-b][1,3]benzothiazol-2(3H)-ones as serotonin3 (5-HT3) receptor antagonists

A series of novel 3-[(4-substituted piperazin-1-yl)alkyl]imidazo[2,1-b][1,3]benzothiazol-2(3H)-ones were prepared by microwave irradiation using alumina as solid support and also by a conventional method. The compounds were characterized by spectral data and the purity was ascertained by microanalysis. The synthesized compounds were evaluated for 5-hydroxytryptamine3 antagonisms in a longitudinal muscle-myenteric plexus preparation from guinea pig ileum against the 5-hydroxytryptamine3 agonist, 2-methyl-5-hydroxytryptamine. Among the test compounds, 3-[2-(4-methylpiperazin-1-yl)ethyl]imidazo[2,1-b][1,3]benzothiazol-2(3H)-one (3b) showed most favorable 5-hydroxytryptamine3 antagonism (pA2 6.7) in the isolated guinea pig ileum.     

Synthesis and evaluation of antioxidant properties of novel 2-[2-(4-chlorophenyl) benzimidazole-1-yl]-N-(2-arylmethylene amino) acetamides and 2-[2-(4-chlorophenyl) benzimidazole-1-yl]-N-(4-oxo-2-aryl-thiazolidine-3-yl) acetamides-I

Our approach was to synthesize and examine the antioxidant properties of some new 2-[2-(4-chlorophenyl)benzimidazole-1-yl]-N-(2-arylmethyleneamino) acetamide (1-18) and 2-[2-(4-chlorophenyl)benzimidazole-1-yl]-N-(4-oxo-2-aryl-thiazolidine-3-yl)acetamide (1t-18t) derivatives. Their in vitro effects on rat liver microsomal NADPH-dependent lipid peroxidation levels (LP assay) and microsomal ethoxyresorufin O-deethylase activities (EROD assay) were determined. The free radical scavenging properties of the compounds were also examined in vitro determining the interaction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The compounds showed significant effects in the above tests.