Synthesis of some novel 2,4-disubstituted thiazoles as possible antimicrobial agents.

A series of novel 4-aryl/chloroalkyl-2-(2,3,5-trichlorophenyl)-1,3-thiazoles (5a-g and 7a-e) were synthesized by condensing 2,3,5-trichlorobenzenecarbothioamide with phenacyl bromide/dichloroacetone. 2,3,5-Trichlorobenzaldehyde thiosemicarbazone on treatment with phenacyl bromide afforded 4-aryl-2-(2,3,5-trichlorophenylidenehydrazino)-1,3-thiazoles (10a-g) in good yield. The newly synthesized compounds are characterized by IR, (1)H NMR and mass spectral studies. These compounds were also screened for their antibacterial and antifungal activities. Preliminary results reveal that some of the synthesized compounds are showing promising antimicrobial activity.

Synthesis, antimicrobial and anti-inflammatory activities of some 1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles and 1,2,4-triazolo[3,4-b][1,3,4]thiadiazines bearing trichlorophenyl moiety.

The reaction of 2,3,5-trichlorobenzoic acid hydrazide with carbon disulfide and potassium hydroxide followed by treatment with hydrazine hydrate afforded 3-(2,3,5-trichlorophenyl)-4-amino-1,2,4-triazole-5-thione (6). Alternatively, this triazole was also synthesized by fusing 2,3,5-trichlorobenzoic acid with thiocarbohydrazide. Condensation of (6) with various aromatic carboxylic acids in the presence of phosphorous oxychloride or with phenacyl bromides afforded two series of fused heterocycles namely 6-(substituted aryl)-3-(2,3,5-trichlorophenyl)-[1,2,4]triazolo[3,4-b][1,3,4]thiadizoles (7) and 6-(substituted aryl)-3-(2,3,5-trichlorophenyl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines (8), respectively. The structures of these newly synthesized compounds are characterised by elemental analysis, IR, (1)H NMR and mass spectroscopic studies. All the synthesized compounds were screened for their antimicrobial and anti-inflammatory activities. Some of the compounds exhibited promising antimicrobial and anti-inflammatory activities.

(2E)-1-(4-Methyl-phen-yl)-3-(2,3,5-trichloro-phen-yl)prop-2-en-1-one.

In the title mol-ecule, C(16)H(11)Cl(3)O, the dihedral angle between the two benzene rings is 33.2 (1)°. The crystal packing is stabilized by C-H⋯O hydrogen bonds.

2-(2-Methoxy-phen-yl)-4,4-dimethyl-4,5-dihydro-1,3-oxazole.

In the title mol-ecule, C(12)H(15)NO(2), the oxazole ring adopts an envelope conformation. Overall, the mol-ecule is approximately planar, the dihedral angle between the mean plane through all but the methyl-ene C atom of the five-membered ring and the aromatic ring being 8.6 (1)°. A weak C-H⋯O inter-action contributes to the stabilization of the crystal structure.

Synthesis and antimicrobial activities of some new triazolothiadiazoles bearing 4-methylthiobenzyl moiety.

A series of substituted triazolothiadiazoles have been synthesized by condensing 4-amino-3-[4-methylthiobenzyl]-4H-1,2,4-triazole-5-thiol (5) with substituted aryl furoic acids/aromatic acids in the presence of POCl3. The triazole (5) was obtained by the fusion of 4-methylthiophenyl acetic acid with thiocarbohydrazide. The structures of newly synthesized compounds are characterized by elemental analysis, IR, 1H NMR and mass spectroscopic studies and were screened for their antimicrobial activities. The preliminary results revealed that some of the compounds exhibited promising antimicrobial activities.