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In a search for new leads towards potent antimicrobial agents, an array of novel (2E)- ethyl-2-(2-(2,4-dinitrophenyl)hydrazono)-4-(naphthalen-2-yl)-6-arylcyclohex-3-ene carboxylates 17-24 were synthesized and characterized through their melting point, elemental analysis, MS, FT-IR, one-dimensional NMR ( ¹H, D2 O exchanged ¹H and 13C), two dimensional HOMOCOR and HSQC spectroscopic data. In-vitro microbiological evaluations were carried out for all the newly synthesized compounds 17-24 against clinically isolated bacterial strains namely Salmonella typhii, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, β-Hemolytic streptococcus and Micrococcus luteus and also fungal strains namely Aspergillus lavus, Aspergillus niger, Mucor, Rhizopus and Microsporum gypseum and inally, the results of their structure activity relationship were discussed. The obtained results can be used as the key step for the building of novel chemical compounds with interesting antimicrobial proiles comparable to that of the standard drugs. [ABSTRACT FROM AUTHOR]

Novel bis cyclohexenone ester derivatives 14--19 were synthesized and characterized by their spectral data. In vitro microbiological evaluations were carried out for all the novel compounds 14--19 against clinically isolated bacterial and fungal strains. Compounds 15, 16, 18 against Staphylococcus aureus, 14, 15 against ββ-Haemolytic streptococcus, 15, 19 against Micrococcus luteus, 17, 18 against Salmonella typhii, 14, 17 against Shigella flexneri, 15 against Escherichia coli, 16 against Pseudomonas aeruginosa, 15, 18, 19 against Klebsiella pneumonia exhibited potent antibacterial activity at an minimum inhibitory concentration (MIC) value of 6.25 μμg/ml, whereas compound 16 against Aspergillus flavus, 17 against A. niger, 16, 18 against Mucor indicus, 15, 17--19 against Microsporum gypseum revealed excellent antifungal activity at an MIC value of 6.25 μμg/ml. [ABSTRACT FROM AUTHOR]

A series of novel hybrid heterocyclic compounds, 3-(3-alkyl-2,6-diarylpiperin-4-ylidene)-2-thioxoimidazolidin-4-ones were synthesised and a comparative study was also carried out under microwave irradiation. The synthesised compounds were characterised by their melting points, elemental analysis, MS, FT-IR, one-dimensional NMR (1H, D2O exchanged 1H and 13C), two dimensional HOMOCOSY and NOESY spectroscopic data. All the synthesised title compounds were screened for their in vitro antibacterial and antifungal activity against clinically isolated strains namely B. subtilis, M. luteus, S. typhii, S. paratyphii B, S. felxneri, P. vulgaris, A. niger, Mucor, Rhizopus and M. gypsuem and the results were discussed. [ABSTRACT FROM AUTHOR]

A series of ethyl 4-(naphthalen-2-yl)-2-oxo-6-arylcyclohex-3-enecarboxylates 8-- 14 and 4,5-dihydro-6-(naphthalen-2-yl)-4-aryl-2 H-indazol-3-ols 15-- 21 were synthesised and characterised by their spectroscopic data. In vitro microbiological evaluations were carried out for all the newly synthesised compounds 8-- 21 against clinically isolated bacterial and fungal strains. Compounds 9, 12 and 20 against Staphylococcus aureus, 10, 12, 20 against ββ-haemolytic streptococcus, 11, 17 against Bacillus subtilis, 12, 16 and 20 against Vibreo cholerae, 13, 16 against Escherichia coli, 13, 16, 18, 19 against Salmonella typhii, 12, 18 against Shigella flexneri, 10 against Salmonella typhii, 10, 13, 17, 18 against Aspergillus flavus, 12, 17, 21 against Aspergillus niger, 12, 15, 17, 18, 20 against Mucor, Rhizopus and Microsporeum gypsuem exhibit potent antimicrobial activity. [ABSTRACT FROM AUTHOR]

A collection of 4-(4-morpholinophenyl)-6-aryl-6 H-1,3-thiazin-2-amines ( 20-28) were synthesized and their in vitro antimicrobial activity was investigated. Compound 21 against P. aeruginosa, 23 against B. subtilis, 24 against V. cholerae and P. aeruginosa, 26 against S. aureus and B. subtilis, 27 against B. subtilis and E. coli, and 28 against all tested bacterial strains exerted excellent antibacterial activity. Compound 20 against A. flavus and Rhizopus, 21, 26 against Rhizopus, 22, 27 against Mucor, 23 against A. flavus, 24 against both A. flavus and Mucor, 25 against all tested strains, and 28 against Rhizopus and M. gypseum exerted excellent antifungal activity. [ABSTRACT FROM AUTHOR]

Objectives and Methods: A collection of novel N-hydroxy-3,3-dimethyl-2,6- diarylpiperidin-4-one oximes 28-32 are synthesized, characterized by melting point, elemental analysis, MS, FT-IR, one-dimensional NMR (1H & 13C) and two dimensional Noesy spectroscopic data and evaluate for their in vitro antibacterial and antifungal activities. Results and Conclusion: Compound 32, exerted a wide range of antibacterial activities against the entire tested gram-positive and gram-negative bacterial strains except Escherichia coli, besides compound 30, which is more active against Klebsiella pneumoniae, a gram-negative coccus. Compound 29 exerted strong antifungal activities against Aspergillus flavus and Microsporum gypseum. In addition, compound 32 is more potent against Rhizopus. [ABSTRACT FROM AUTHOR]

A new series of novel 3-azabicyclic spiro 1′,2′,4′-triazolidin-3′-thiones 15-21 catalyzed by potassium superoxide under microwave irradiation have been synthesized and studied for their in vitro microbiological evaluation on clinically isolated bacterial strains namely Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Pseudomonas aeuroginosa and fungal strains namely Aspergillus niger, Candida albicans, Candida 6 and Candida 51. Results of the in vitro microbiological evaluation of the synthesized compounds are discussed. [ABSTRACT FROM AUTHOR]

Compounds 4-(4-morpholinophenyl)-6-phenylpyrimidin-2-amine 20, 4-(4-methoxyphenyl)-6-(4-morpholinophenyl)pyrimidin-2-amine 23, 4-(4-bromophenyl)-6-(4-morpholinophenyl)pyrimidin-2-amine 25, 4-(3-chlorophenyl)-6-(4-morpholinophenyl) pyrimidin-2-amine 27, and 4-(3-fluorophenyl)-6-(4-morpholinophenyl)pyrimidin-2-amine 28 exerted excellent antibacterial activity against V. cholerae. Compounds 4-(4-chlorophenyl)-6-(4-morpholinophenyl)pyrimidin-2-amine 22, 25, 4-(4-morpholinophenyl)-6-(3-nitrophenyl)pyrimidin-2-amine 26, and 28, which contained electron-withdrawing chloro, bromo, nitro, and fluoro functional groups, respectively, at the para/ meta position of the phenyl ring attached to the pyrimidine ring promoted much activity against S. aureus. Compounds 4-(4-fluorophenyl)-6-(4-morpholinophenyl)pyrimidin-2-amine 24 and 25 (against β-hemolytic Streptococcus) and compound 28 (against S. felxneri) showed pronounced activity. Compounds 26 and 28 (against K. pneumoniae) and compounds 24, 25, and 28 (against P. aeruginosa) exerted strong antibacterial activity. Compounds 22 and 25 promoted much antifungal activity against A. flavus, while compounds 24 and 25 registered maximum activity against Mucor. Compounds 23 (against C. albicans) and 27 and 28 (against Rhizopus) promoted good activity. [ABSTRACT FROM AUTHOR]

A series of novel 2-phenyl-3-(4,6-diarylpyrimidin-2-yl)thiazolidin-4-ones 23-33 were synthesized, and studied for their in vitro antibacterial and antifungal activities against clinically isolated strains. Generally compounds possessing electron donating groups showed good antibacterial activity. Compound 31, which contain both electron withdrawing chloro and electron donating methyl groups showed potent activity against all the tested Gram positive and Gram negative bacterial strains whereas compounds 32 and 33 which contain electron donating methoxy functional group at the para position of the phenyl ring attached to pyrimidine ring showed promising activity against S.aureus, S.typhii and E.coli. Compounds 32 and 33, both containing electron withdrawing groups (-Cl, -F) showed excellent activities against all the tested A. flavus, Mucor, Rhizopus and M.gypsuem fungal strains. while against Mucor, compound 27 which contains an electron donating methyl group at the para position of the phenyl ring attached to pyrimidine ring showed promising activity. Also compound 31, which contains both electron withdrawing chloro and electron donating methyl groups showed potent activity against A. flavus and Rhizopus. [ABSTRACT FROM AUTHOR]

Some 2,6-diarylpiperidin/tetrahydrothiopyran/tetrahydropyran-4-one oximes were synthesized in dry media under microwave irradiation and were evaluated for their in vitro antibacterial activity against clinically isolated bacterial strains i.e. S.aureus, β-H.Streptococcus, E.coli, P.aeruginosa, S.typhii and in vitro antifungal activities against fungal strains i.e. C.albicans, Rhizopus, A.niger and A.flavus. Structure-activity relationships for the synthesized compounds showed that compounds 12 and 15 exerted excellent antibacterial activity against all the tested bacterial strains except 15 against S.aureus and β-H.streptococcus. Against C.albicans and A.flavus, compound 15 exerted potent antifungal activities while against Rhizopus, compound 16 showed promising activity. [ABSTRACT FROM AUTHOR]

Some novel 'tailor-made' compounds, 6,6-dimethyl-7,9-diaryl-1,2,4,8-tetraazaspiro[4.5]decan-3-thiones 23-27 have been studied for their in vitro antibacterial activity against Staphylococcus aureus, β-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, Shigella felxneri, Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa and anti-fungal activity against Aspergillus flavus, Mucor, Rhizopus and Microsporum gypsuem. Compounds 24 and 25 exerted potent antibacterial activity against S. aureus, β-H. streptococcus, E. coli and P. aeruginosa whereas all compounds 23-27 exerted strong in vitro antifungal activity against A. flavus, Mucor and Rhizopus. [ABSTRACT FROM AUTHOR]

New 4,6-diaryl-4,5-dihydro-2-phenyl-2H-indazol-3-ols 25-32 were designed, synthesized and in vitro microbially evaluated using clinically isolated bacterial strains viz Staphylococcus aureus, β-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, Shigella felxneri and fungal strains viz Aspergillus flavus, Mucor, Rhizopus and Microsporum gypsuem. Results of this study showed that the nature of the substituents on the phenyl rings viz., methyl, methoxy, chloro, nitro as well as the bromo functions at the meta and para positions of the aryl moieties determined the nature and extent of the activity of the fused indazolonol compounds 25-32. [image omitted] [ABSTRACT FROM AUTHOR]

New 3-chloro-1-hydroxy-2,6-diarylpiperidin-4-ones 18–22 were synthesized, characterized bymelting point, elemental analysis, MS, FT-IR, one-dimensional NMR (1H & 13C) spectroscopic data and evaluated for their in vitro antibacterial and antifungal activities. All the newly synthesized compounds exerted a wide range of antibacterial activities against the entire tested grampositive and gram-negative bacterial strains except Escherichia coli. Compounds 21 and 22 exerted strong antifungal activities against Aspergillus flavus, mucor and Microsporum gypsuem. In addition, compound 20 was more potent against Rhizopus. [ABSTRACT FROM AUTHOR]

A novel class of 4,6-diaryl-4,5-dihydro-3-hydroxy-2[H]-indazoles 25-32 were synthesized and evaluated for their in vitro antibacterial and antifungal activities. Four Compounds, which all possessed electron withdrawing functional groups (-Cl, -NO2, -Br) 27, 28, 30 and 32 were more potent against the tested bacterial/fungal strains than the standard bacterial and fungal drugs ciprofloxacin and fluconazole respectively. [ABSTRACT FROM AUTHOR]

Compound 26 is more potent against Escherichia coli. and 24 is more active against Staphylococcus aureus, β-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, and Shigella flexneri than the standard drug ciprofloxacin. Moreover, of all the compounds tested, 26 is more effective against Aspergillus flavus and Mucor, than the standard drug fluconazole. [ABSTRACT FROM AUTHOR]

A novel method has been developed for the synthesis of 6-aryl-1,2,4,5-tetrazinan-3-ones through a one-pot reaction of urea, various substituted aromatic benzaldehyde having electron donating and electron withdrawing groups and ammonium acetate in the presence of reusable NaHSO4.SiO2 heterogeneous catalyst in dry media under microwave irradiation. FT-IR, 1H NMR, D2O Exchange, 13C NMR, Heteronuclear Single Quantum Correlation (HSQC) spectra, MS and elemental analysis characterized all the synthesized compounds. In vitro antibacterial/fungal activities were evaluated for six new compounds. The antibacterial studies revealed that compounds 1-6 had better activity against tested Gram-positive and Gram-negative organisms. Compounds 1 and 5 were more active against β-Heamolytic streptococcus, a Gram-positive bacteria and Pseudomonas, a Gram-negative bacteria, respectively, than the standard drug ciprofloxacin. Besides, of all the compounds tested, compound 5 was more effective against Aspergillus flavus, a fungal strain than the standard drug fluconazole. [ABSTRACT FROM AUTHOR]

A convenient method for the 'one-pot' synthesis of novel target molecule 2,7-diaryl-[1,4]-diazepan-5-ones from the respective 2,6-diaryl-piperidin-4-ones was catalyzed by NaHSO4.Al2O3 heterogeneous catalyst in dry media under microwave irradiation in solvent-free conditions. Moreover, the catalyst could be recovered and re-used up to 4 times after washing with ethyl acetate. They were evaluated for potential antibacterial activity against Staphylococcus aureus, β-Haemolytic streptococcus, Vibreo cholerae, Salmonella typhii, Escherichia coli, Klebsiella pneumonia, Pseudomonas and antifungal activity against Aspergillus flavus, Aspergillus fumigatus, Mucor, Candida albicans and Rhizopus. Structure-Activity Relationship (SAR) led to the conclusion that, of all the compounds 25-32 tested, compound 30 exerted strong in vitro antibacterial activity against S. aureus, S. typhii, and Pseudomonas and all the compounds 25-32 were less active against E. coli, whereas all the compounds 25-32 displayed potent in vitro antifungal activity against all the fungal strains used, except compound 30, which was more effectual against Mucor. [ABSTRACT FROM AUTHOR]

A novel 'one-pot' synthesis of 6-aryl-1,2,4,5-tetrazinan-3-thiones is carried out by the three-component coupling of thiourea, various structurally diverse aromatic aldehydes and ammonium acetate in the presence of reusable NaHSO4·SiO2 heterogeneous catalyst in dry media under microwave irradiation. FT-IR, 1H NMR, D2O Exchange, HOMOCOR, 13C NMR, MS and elemental analysis characterize all the synthesized compounds. In vitro antibacterial/fungal activities are carried out for all the synthesized eight new compounds. All the compounds are more active against bacterial strains namely Staphylococcus aureus, β-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, Shigella felxneri, Klebsiella pneumonia and Pseudomonas except compounds 1 and 6, while compound 6 shows promising activity against Salmonella typhii. Moreover, of all the compounds tested, compounds 3 and 8 are more effectual against all the tested fungal strains. [ABSTRACT FROM AUTHOR]

Abstract: Biolabile 2-morpholino-N-(4,6-diarylpyrimidin-2-yl)acetamides 34–42 have been synthesized and evaluated for their in vitro antibacterial and antifungal activities. The minimum inhibitory concentration tested for the same compounds against the same set of bacterial and fungal strains shows that the compounds 36 and 38 against β-Heamolytic streptococcus and Klebsiella pneumonia, 40 against Escherichia coli and Pseudomonas, have excellent antibacterial activity. Compounds 36, 38 and 42 show inhibition against Aspergillus flavus, compound 41 against Microsporum gypsuem, 42 against Mucor, and compounds 39 and 40 against Rhizopus. [Copyright &y& Elsevier]

Abstract: In the present work, a new series of bis hybrid heterocycle comprising both piperidine and thiohydantoin nuclei together namely 3-(3-alkyl-2,6-diarylpiperin-4-ylidene)-2-thioxoimidazolidin-4-ones 46–60 was synthesized by the treatment of the respective thiosemicarbazones 31–45 with chloroethyl acetate and anhydrous sodium acetate in refluxing ethanol for 4h and were characterized by melting point, elemental analysis, MS, FT-IR, one-dimensional NMR (1H, D2O exchanged 1H and 13C), two dimensional HOMOCOSY and NOESY spectroscopic data. In addition, the title compounds were screened for their antimicrobial activities against a spectrum of clinically isolated microbial organisms. Compounds 47–50, 52–55 and 57–60 with fluoro, chloro, methoxy or methyl functions at the para position of phenyl rings attached to C-2 and C-6 carbons of piperidine moiety along with and without methyl substituent at position C-3 of the piperidine ring exerted potent biological activities against Staphylococcus aureus, β-Hemolytic streptococcus, Vibrio cholerae, Escherichia coli, Pseudomonas aeruginosa, Aspergillus flavus, Candida albicans, Candida 6 and Candida 51 at a minimum inhibitory concentration. [Copyright &y& Elsevier]