Quality standards for Hutabhugādi cūrṇa (Ayurvedic Formulary of India).

In India, herbal medicines are mainly based on the Ayurvedic system. The main drawback of traditional medicines is a lack of standardized products. Standardization of any herbal formulation is essential in order to assess the quality, purity, safety, and efficacy of drugs based on the analysis of their active properties.

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.

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.

Antimicrobial studies of 2,4-dichloro-5-fluorophenyl containing oxadiazoles.

A series of 2,4-dichloro-5-fluorophenyl containing 1,3,4-oxadiazoles (10 and 11) were synthesized by POCl3 cyclization of 2,4-dichloro-5-fluorobenzoyl hydrazide (4) and 2-(2,4-dichloro-5-fluorophenyl)cinchoninyl hydrazide (8) with aryloxyacetic acids (9). The structures of newly synthesized compounds were characterized by spectral and elemental analyses. All the compounds were screened for their antibacterial and antifungal activities.

Synthesis and antimicrobial studies of novel dichlorofluorophenyl containing aminotriazolothiadiazines.

Dichlorofluorophenyl containing aminotriazolothiadiazines (6) were synthesized by initial condensation of 2-chloro-N-(substituted phenyl) acetamides (4) with triazole (3) and further cyclization using POCl(3). The structures of newly synthesized compounds were confirmed by IR, NMR, mass and elemental analysis. All the compounds were screened for their antibacterial and antifungal activities.

Convenient one pot synthesis and antimicrobial evaluation of some new Mannich bases carrying 4-methylthiobenzyl moiety.

Two new series of Mannich bases, namely, 1-(morpholino)methyl-3-(4-methylthiobenzyl)-4-(substituted arylidene)amino-1,2,4-triazol-5-thiones 3 and 1-(N-methylpiperazino)methyl-3-(4-methylthiobenzyl)-4-(substituted arylidene)amino-1,2,4-triazol-5-thiones 4 have been synthesized by a three-component Mannich reaction (MCR) involving 3-(4-methylthiobenzyl)-4-(substituted arylidene)amino-5-mercapto-1,2,4-triazoles 2, formaldehyde and morpholine/N-methylpiperazine. The newly synthesized compounds were well characterized by elemental analysis, IR, (1)H NMR and mass spectral studies. They were also screened for their antibacterial and antifungal activities against a variety of microorganisms and the results of such studies have been discussed in this article.

Convenient one pot synthesis of some novel derivatives of thiazolo[2,3-b]dihydropyrimidinone possessing 4-methylthiophenyl moiety and evaluation of their antibacterial and antifungal activities.

A series of new 2-(arylidene/5-arylfurfurylidene)-5-(4-methylthiophenyl)-6-carbethoxy-7-methyl-5H-thiazolo[2,3-b]pyrimidin-3(1H)-ones 2 and 3 have been synthesized by a three component (MCR) reaction involving 4-(4-methylthiophenyl)-5-carbethoxy-6-methyl-3,4-dihydropyrimidin-2(1H)-thione 1, monochloroacetic acid and arylaldehydes/arylfurfuraldehydes, respectively. The newly synthesized compounds were well characterized by elemental analysis, IR, (1)H NMR and mass spectral studies. The newly synthesized compounds were screened for their antibacterial and antifungal activities and have exhibited moderate to excellent growth inhibition of bacteria and fungi.

Synthesis and antimicrobial studies on novel chloro-fluorine containing hydroxy pyrazolines.

A series of chloro-fluorine containing chalcones (3) were prepared by Claisen-Schmidt condensation. Chalcone dibromides (4) were obtained by the bromination of chalcones at room temperature. Treatment of chalcone dibromides (4) with aryloxy acid hydrazides (5) in the presence of triethylamine gave chloro-fluorine containing hydroxy pyrazolines (7) rather than the expected 1-aryloxy-3-aryl-5-aryl pyrazoles (6).

Synthesis and biological activity of Schiff and Mannich bases bearing 2,4-dichloro-5-fluorophenyl moiety.

A series of 2,4-dichloro-5-fluorophenyl bearing Mannich base (4 and 5) was prepared from triazole Schiff bases (3) by aminomethylation with formaldehyde and secondary/substituted primary amines. All newly synthesized compounds were screened for their antimicrobial activity. Compounds 3c, 4c, 4e and 4f exhibited promising antibacterial and compounds 3c, 5c, 5e and 5f showed good antifungal activity.

Synthesis of some novel pyrazolo[3,4-d]pyrimidine derivatives as potential antimicrobial agents.

The reaction of 4-hydrazino-8-(trifluoromethyl)quinoline (2) with ethoxymethylenecyanoacetate afforded ethyl 5-amino-1-[8-(trifluoromethyl)quinolin-4-yl]-1H-pyrazole-4-carboxylate (3) and that with ethoxymethylenemalononitrile afforded 5-amino-1-[8-(trifluoromethyl)quinolin-4-yl]-1H-pyrazole-4-carbonitrile (5). Compounds 3 and 5 were hydrolyzed to get 5-amino-1-[8-(trifluoromethyl)quinolin-4-yl]-1H-pyrazole-4-carboxylic acid and then reacted with acetic anhydride to afford 6-methyl-1-[8-(trifluoromethyl)quinolin-4-yl]pyrazolo[3,4-d]oxazin-4-one (6), which was condensed with different aromatic amines to give a series of 5-substituted 6-methyl-1-[8-(trifluoromethyl)quinolin-4-yl]-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-ones (7). Compounds 3 and 5 also reacted with formamide, urea, and thiourea affording the corresponding pyrazolo[3,4-d]pyrimidines (8-13), respectively.

Synthesis, characterization and antimicrobial activity of some substituted 1,2,3-triazoles.

Two substituted 1,2,3-triazoles 4 and 6 have been synthesized by the 1,3-dipolar cycloaddition reaction of 4-azido-8-(trifluoromethyl)quinoline 2 with ethyl acetoacetate and acetylacetone, respectively. The reaction of 2 with ethyl acetoacetate afforded 1-[8-(trifluoromethyl)quinolin-4-yl]-5-methyl-1H-1,2,3-triazole-4-carboxylic acid 3 and with acetylacetone afforded 1-{1-[8-(trifluoromethyl)quinolin-4-yl]-5-methyl-1H-1,2,3-triazol-4-yl}ethanone 5. Compound 3 is converted into its corresponding acid hydrazide and then condensed with different aromatic aldehydes to yield Schiff's base, N-[1-arylmethylene]-1-[8-(trifluoromethyl)quinolin-4-yl]-5-methyl-1H-1,2,3-triazole-4-carbohydrazides 4.