Synthesis, structural and biochemical activity of pyridine substituted pyrrole ligands and their mononuclear Cu(II), Ni(II) and Co(II) complexes

Monomeric copper(II), nickel(II) and Co(II) complexes of 6-(2,5-dimethyl-1 H-pyrrol-1-yl)pyridin-2-amine (dmpypr) and 2,6-bis(2,5- dimethyl-1 H-pyrrol-1-yl)pyridine (tmpypr) were prepared and characterized by elemental analyses, magnetic moments, 1H and 13C NMR, IR, mass spectral studies. The mononuclear metal complexes of dmpypr and tmpypr were found to have a 1:2 metal:lig and ratio. Elemental analyses, stoichiometric and spectroscopic data of metal complexes indicated that the metal ions were coordinated to the -NH 2 and C=N group nitrogen atoms. All of the data obtained from spectral studies supported the structural properties of ligands and their metal complexes. The free ligands and their metal complexes showed antimicrobial activity against S. aureus but no antifungal activity was observed against yeast like fungi. Among them, copper complexes and free ligands showed a narrow range of inhibitory activity against Mycobacterium smegmatis. Free ligands (2, 3), were found to have activity against Saccharomyces cerevisiae (Sc)

Synthesis of some new 1,3,4-thiadiazol-2-ylmethyl-1,2,4-triazole derivatives and investigation of their antimicrobial activities

PubMed: 191671364-Amino-2-[(5-arylamino-4,5-dihydro-1,3,4-thiadiazol-2-yl)methyl]-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-ones (3a-c) were obtained in acidic media via the formation of 2-[(4-amino-3-aryl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)acetyl]-N-arylhydrazinecarbothioamides (2a-c), and then, compound 3b was converted to methylated derivative, 4. The basic treatment of carbothioamide derivatives, 2a-c, afforded 4-amino-2-[(4-aryl-5-sulphanyl-4H-1,2,4-triazol-3-yl)methyl]-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-ones (5a-c). The alkylation reactions of compounds 4H-1,2,4-triazol-3-ylmethyl-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (5a-c) were performed by using methyl iodide or ethyl bromide in the presence of sodium ethoxide, while the treatment of the same intermediates, 5a-c, with aromatic aldehydes produced 2-{[4-(4-aryl)-5-sulphanyl-4H-1,2,4-triazol-3-yl]methyl}-4-(arylmethylene)amino-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-ones (8a-d). The synthesis of 4-amino-(or arylideneamino)-5-(4-methylphenyl)-2-{[(4-methylpiperazin-1-yl or morpholin-4-ylethyl)methyl]-4-aryl-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-3-yl}methyl-2,4-dihydro-3H-1,2,4-triazol-3-ones (7a, b and 9) was performed by a one pot three-component Mannich reaction involving the corresponding compounds, 4-(substituted)amino-4H-1,2,4-triazol-3-ylmethyl-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one derivatives 5a, b and 8a, methylpiperazine or 2-(4-morpholino)ethylamine and formaldehyde. The newly synthesized compounds were well characterized by elemental analyses, IR, 1H NMR, 13C NMR and mass spectral studies. They were also screened for their microbial activities. The antimicrobial activity study revealed that some of which 2a, c, 3c, 5a-c, 8a-d showed good activity against a variety of microorganisms. © 2008 Elsevier Masson SAS. All rights reserved.Karadeniz Teknik Üniversitesi: 2005.111.002.3This project was supported by Karadeniz Technical University, BAP, Turkey (Ref. No. 2005.111.002.3) and is gratefully acknowledged

Synthesis of some new 1,2,4-triazoles, their Mannich and Schiff bases and evaluation of their antimicrobial activities

PubMed: 186760624-Phenyl-5-pyridin-4-yl-4H-1,2,4-triazole-3-thiol (3) was obtained in basic media via the formation of 2-isonicotinoyl-N-phenylhydrazinecarbothioamide (2), and converted to some alkylated derivatives (4a,b) and Mannich base derivatives (5a-c). 2-[(4-Phenyl-5-pyridin-4-yl-4H-1,2,4-triazol-3-yl)thio]acetohydrazide (7) that was obtained by using compound 3 as precursor in two steps was converted to thiosemicarbazide derivative (8), Schiff base derivatives (9) and 5-{[(4-phenyl-5-pyridin-4-yl-4H-1,2,4-triazol-3-yl)thio]methyl}-1,3,4-oxadiazole-2-thiol (10). Moreover, 5-{[(4-phenyl-5-pyridin-4-yl-4H-1,2,4-triazol-3-yl)thio]methyl}-3-{[(2-morpholin-4-ylethyl)amino]methyl}-1,3,4-oxadiazole-2(3H)-thione (11) was synthesized via reaction of compound 10 with 2-(4-morpholino)ethylamine. The treatment of compound 8 with NaOH gave 4-(4-methylphenyl)-5-{[(4-phenyl-5-pyridine-4-yl-4H-1,2,4-triazol-3-yl)thio]methyl}-4H-1,2,4-triazole-3-thiol (12), while the acidic treatment of compound 8 afforded 5-{[(4-phenyl-5-pyridin-4-yl-4H-1,2,4-triazol-3-yl)thio]methyl}-2(4-methylphenyl)-amino-1,3,4-thiadiazole (14). N-Methyl derivative of compound 14 and a Mannich base derivative of compound 12 were synthesized from the reactions of these precursors with methyl iodide and methyl piperazine, respectively. All newly synthesized compounds were screened for their antimicrobial activities. The antimicrobial activity study revealed that all the compounds screened showed good or moderate activity except compounds 3, 5c, 7, 9c, 9e, 9g, 9h, 11, and 13. © 2008 Elsevier Masson SAS. All rights reserved.Karadeniz Teknik Üniversitesi: 2005.111.002.3This project was supported by Karadeniz Technical University, BAP, Turkey (ref. no. 2005.111.002.3) and is gratefully acknowledged

Antimicrobial activity of Bacillus strains isolated from spring water and a novel bacteriocin: RS108

The aim of this research was to investigate the bacteriocins produced by Bacillus strains isolated from the spring water of Rize, in Turkey. Bacillus cereus RS108 was identified by both conventional and molecular methods, bacteriocin RS108 which was produced by RS108, was partially characterized. A broad range of indicator strains, including several species of bacteria and yeast like.fungi, was inhibited by a crude bacteriocin obtained from culture supernatant fluid. The best antimicrobial activity of RS108 was detected on S. pyogenes, L. monocytogenes, and another B. cereus strains-and at the late exponential growth phase. RS108 was stable at 90°C, but the activity was lost when the temperature reached 100 °C. It was inactivated by proteinase K. It was resistant 10% ration of some solvent (chloroform, ethanol etc.), but sensitive high concentration. Bacteriocin activity was observed in the pH range of 3.0-9.0. SDS-PAGE analysis of the partially purified bacteriocin shows that the molecular weight of bacteriocin RS108 is approximately 4 kDa

Synthesis of some new 1,2,4-triazoles starting from isonicotinic acid hydrazide and evaluation of their antimicrobial activities

PubMed: 196473525-Pyridin-4-yl-1,3,4-oxadiazole-2-thiol (2) was obtained from the reaction of isonicotinic acid hydrazide with carbon disulfide in basic media and converted into 4-amino-5-pyridin-4-yl-4H-1,2,4-triazole-3-thiol (5) by the treatment with hydrazine hydrate. The synthesis of 3 and 6 was performed from the reaction of 2 and 5 with ethyl bromide. The treatment of 5 with 4-fluorobenzaldehyde or indol-3-carbaldehyde resulted in the formation of 4-[(arylmethylene)amino]-5-pyridin-4-yl-4H-1,2,4-triazole-3-thiols (7a and 7b). The reactions of 2, 5 and 7a with some primary and secondary amines in the presence of formaldehyde afforded the corresponding Mannich bases, 4a, 4b, 9a-9c and 8. All newly synthesized compounds were screened for their antimicrobial activity. The antimicrobial activity study revealed that all the compounds screened showed good or moderate activity except compounds 2, 7a, 7b, 8 and 9b. © 2009

Cyclization of some carbothioamide derivatives containing antipyrine and triazole moieties and investigation of their antimicrobial activities

PubMed: 20727622Acetohydrazide derivative containing both antipyrine and triazole nuclei (5) was obtained starting from ethyl hydrazinecarboxylate derivative (2) and 4-aminoantipyrine (1) by three steps. The treatment of compound 5 with CS 2 afforded the conversion of hydrazide function into 5-mercapto-1,3,4-oxadiazole ring leading to the formation of 7. Then, 7 gave the product containing triazolotriazine moiety (9) by the reaction with hydrazine hydrate. The synthesis of the compounds incorporating the 1,3,4-thiadiazole (10a-c), 1,2,4-triazole (11a-c) or 1,3-thiazole (12, 13) nucleus as third heterocycle was performed by the acidic or basic treatment of compounds 6a-c which were obtained from the reaction of 5 with several isothiocyanates, or by the condensation of 6a with two different phenacyl bromides, respectively. The antimicrobial activity study revealed that all the compounds showed good activities except 3-5. © 2010 Elsevier Masson SAS. All rights reserved.107T333 Türkiye Bilimsel ve Teknolojik Araştirma KurumuThis work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK, Project no: 107T333 )

Composition and antimicrobial activity of essential oil from the flower of Rhododendron luteum Sweet

Essential oil from air-dried flower of Rhododendron luteum Sweet (Ericaceae), was obtained by hydrodistillation in a Clevenger-type apparatus and analyzed by GC-MS and GC-FID. Sixty-four components were identified in the oil. The most abundant components in the investigated essential oil from the flower of R. luteum was found to be a-cadinol (8.9 %), d-cadinene (7.6 %), ?-terpineol (7.2 %), benzyl salicylate (6.2 %), ?-muurolene (4.1 %) and 1,6-germacradien-5?-ol (3.4 %). The antimicrobial activity of the isolated essential oil was investigated and it showed moderate antimicrobial activity against Serratia marcescens, Enterococcus faecalis and Staphylococcus aureus, but no antifungal activity was observed against yeast like fungi

Antimicrobial activity and chemical composition of the essential oil from Campanula glomerata L. subsp. hispida (Witasek) Hayek

The volatile components of the essential oil from Campanula glomerata L. subsp. hispida (Witasek) Hayek was analyzed by GC and GCMS. Forty-eight compounds representing 89.0 % of the total oil were characterized and the main constituents of this specie were found to be hexadecanoic acid (24.51 %), docosane (15.9 %), isocitronellene (12.6 %), heneicosane (4.6 %), hexahydrofarnesyl acetone (3.2 %), ?-tricosene (1.6 %), octadecanol (1.4 %), caryophyllene oxide (1.3 %), ?-funebrene (1.2 %), ?-thujaplicinol (1.1 %), pentadecanoic acid (1.1 %), tricosane (1.1 %), (2E,4E)-decadienal (1.0 %), (E)-?-damascenone (1.0 %) and (E)-caryophyllene (1.0 %). The antimicrobial activity of the isolated essential oil of the plant was also investigated and it showed moderate antimicrobial and antifungal activities against Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus, Mycobacterium smegmatis, Candida albicans and Saccharomyces cerevisiae

Antimicrobial activity and volatile constituents of the flower, leaf, and stem of Paeonia daurica grown in Turkey

The volatile constituents of the essential oils from the flower, leaf, and stem of Paeonia daurica Andrews were analyzed by GC and GC-MS. A total of 74 compounds were identified, constituting over 95.0%, 80.8%, and 98.2% of the oil composition of the flower, leaf, and stem of P. daurica, respectively. Aldehydes were shown to be the main group of constituents of the flower and stem parts, at 39.1% and 79.8%, respectively. However, the major group in the leaf oil was found to be oxygenated monoterpenes (43.5%). Salicylaldehyde (20.7% and 79.5%) was the major component of the flower and stem oils of P. daurica, respectively. Linalool (31.4%) was the main compound of the leaf oil. The antimicrobial activity of the isolated essential oils of the plant was also investigated, and they showed moderate antibacterial activity against tested microorganisms. © 2011 Tübïtak

Volatile constituents and antimicrobial activity of the essential oils from Cladonia rangiformis Hoffm. and Cladonia furcata (Huds.) Schrad

This study was designed to examine the chemical compositions and antimicrobial activities of the essential oils from Cladonia rangiformis Hoffm. and Cladonia furcata (Huds.) Schrad. The essential oils were isolated by hydrodistillation and analyzed with GC and GC-MS and screened for their in vitro antimicrobial activity in a microdilution assay. In total, 25 and 12 compounds were identified from the oil of C. rangiformis and C. furcata, accounting for 89.2 % and 91.6 % of the detected GC peak areas, respectively. The essential oils consisted mainly of alcohols (29.4 % and 1.6 %), ketone (21.7 % and 18.6 %) and hydrocarbons (13.1 % and 57.6 %). The major compound of the essential oils was 3-octanone (21.7 % and 18.6 %), respectively. The inhibitory effects of the essential oils of C. rangiformis and C. furcata, were tested against seven bacterial species using the disc-diffusion method and C. rangiformis oil exhibited the antimicrobial and antifungal activity against Enterococcus faecalis and Candida albicans (MIC = 306.2 ?g/?L, each), whereas, C. furcata oil showed only antifungal activity against the pathogenic yeast C. albicans (MIC = 784.4 ?g/?L)