Synthesis and antimicrobial evaluation of novel alkylated piperazine-based fluoroquinolone carboxylate derivatives

474-484In the present study, to synthesize quinolone-piperazine alkylated analogues, initially 3,4-difluoro nitro benzene is reduced to yield 3,4-difluorobenzenamine which is treated with diethyl ethoxymethyl enemalonate to yield diethyl 2-((3,4-difluorophenylamino) methylene) malonate. This has been further cyclized to produce ethyl 6,7-difluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate which is treated with iodoethane to produce ethyl 1-ethyl-6,7-diifluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate. This is hydrolyzed and subsequent nucleophilic substitution with piperazine at 7th position gives quinolone-piperazine derivative. This is alkylated to yield 1-ethyl-6-fluoro-7-(4-alkylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid which is treated with ethanol to afford the desired ethyl 1-ethyl-6-fluoro-7-(4-hexylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylate derivatives. Based on the antimicrobial activity studies, hexyl analog 8a exhibits potent antimicrobial activity against Staphylococcus aureus MTCC 96, Bacillus subtilis MTCC 121, Micrococcus luteus MTCC 2470 (MIC value 1.9µg/mL), with respect to other synthesized compounds and reference drug ciprofloxacin. 8b (heptyl analogue) and 8c (nonyl analogue) show significant activity with MIC value 3.9µg/mL. In the case of antifungal screening, 8a, 8b and 8c show significant antifungal activity against Candida albicans MTCC 3017with MIC value ranged from 3.9 to 7.8µg/mL. Compounds 8a (butyl) shows potent minimum bactericidal concentration activity with MIC value 3.9µg/mL against the tested strains

Synthesis, cytotoxic evaluation of novel 2-((1H-indol-3-yl) methyl)-5-alkyl-1,3,4-oxadiazole and 2-alkyl-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole derivatives

465-473Interest in the biological applications of oleochemicals has resulted in the development of new heterocyclic compounds from the fatty acids which are renewable raw materials. In the present study the synthesis of hybrid compounds by involving fatty acids, indole-3-acetic acid (heteryl) and trimethoxy benzoic acid (aryl) to derive 2, 5-substituted 1,3,4-oxadiazole moiety using molecular hybridization approach has been carried out. A series of novel 2-((1H-indol-3-yl) methyl)-5-alkyl-1,3,4-oxadiazoles 4a-j and 2-alkyl-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole 8a-j analogues have been synthesized and evaluated for their cytotoxicity against A549, MCF-7 and HeLa cell lines. Almost all the tested compounds reveal cytotoxicity against all the cell lines, especially 2-((1H-indol-3-yl) methyl)-5-alkyl-1,3,4-oxadiazoles based compounds (4c, 4d, 4e) which display potent inhibitory activity with IC50 values ranging between 8.26 to 11.36 μM

Synthesis, antimicrobial and cytotoxicity studies of novel undecenoic acid-based triazolothiadiazole derivatives

420-430In the present study, synthesis, antimicrobial and cytotoxic activity studies of 3,6-disubstituted-[1,2,4]triazolo [3,4-b][1,3,4]thiadiazole series compounds have been carried out. Compounds 6d, 6i, 6k, 6p, 6q, 6r, 6s and 6t exhibit promising activity with MIC value of 3.9 μg/mL against some of the tested bacterial strains. Compounds 6r and 6s consistently show promising minimum bactericidal concentration activity with MBC value of 7.8 μg/mL against Staphylococcus aureus MTCC 96 strain. Cytotoxic evaluation study claims that most of the compounds exhibit significant cytotoxicity against all the studied cancer cell lines. Particularly, compounds 6c, 6k, 6l, 6n and 6t against HeLa cell line and compounds 6c and 6h against B16-F10 cell line exhibit promising activities with IC50 values ranging from 6.34 to 9.99 μM. Further, most of the compounds are non-toxic against Chinese hamster ovary cell (CHO-K1) normal cell

Synthesis, cytotoxic evaluation of substituted cinnamic-based 1,2,4-triazolo thiadiazoles

475-481In an attempt to find a new class of cytotoxic agents, a series of 3,6-disubstituted-[1,2,4] triazolo[3,4-b] [1,3,4]thiadiazoles have been synthesized using undecenoic acid and various cinnamic acids. The structures of the synthesized compounds have been confirmed using 1H and 13C NMR, IR and mass spectroscopy. The prepared compounds have been evaluated for their in vitro cytotoxic activities against four human cancer cell lines namely, HeLa, B16-F10, SKOV3, MCF7 and CHO-K1 Normal Cell line using MTT assay. Compounds 6a and 6h show promising activity against HeLa (IC50 value 8.92µM) and SKOV3 cell lines (IC50 value 9.43 µM). Majority of the compounds show significant activities against HeLa cell line with the IC50 values ranging from 8.92 to 13.44 μM. All the compounds show good activity against SKOV3 cell line with the IC50 values ranging from 9.43 to 19.34 μM. Majority of the compounds are non toxic towards the Chinese hamster ovary (CHO-K1) normal cell line

Synthesis and biological evaluation of some new N-fatty acyl derivatives of 4,5-dimethoxy tryptamine

531-541The aim of this study is to synthesize and examine the in vitro anticancer, antioxidant and antimicrobial activities of N-fatty acyl derivatives of 4,5-dimethoxy tryptamine. A series of new N-fatty acyl derivatives of 4,5-dimethoxy tryptamine compounds derived from 2,3-dimethoxy benzaldehyde have been prepared. The synthesized compounds have been characterized and screened for anticancer, antioxidant and antimicrobial activities. The synthesized derivatives have been evaluated for their cytotoxicity on various cell lines. Compounds 9a and 9g have shown promising cytotoxicity, while compounds 9c, 9d and 9e have shown moderate activity for all the tested cancer cell lines. The antioxidant activities have been determined with regard to DPPH radical scavenging activity, superoxide free radical scavenging activity and inhibition of lipid peroxidation. Based on the results, it has been observed that N-fatty acyl derivatives of 4,5-dimethoxy tryptamine exhibit promising antioxidant activity. In particular, the undecenoic acid-based derivative 9d shows good antioxidant activity in all the three assays. Further, the compound 9d exhibits significant antimicrobial activity against Bacillus subtilis MTCC 121 with MIC value of 15.6 µg/mL

Synthesis, antimicrobial and cytotoxicity studies of novel undecenoic acid-based triazolothiadiazole derivatives

In the present study, synthesis, antimicrobial and cytotoxic activity studies of 3,6-disubstituted-[1,2,4]triazolo [3,4-b][1,3,4]thiadiazole series compounds have been carried out. Compounds 6d, 6i, 6k, 6p, 6q, 6r, 6s and 6t exhibit promising activity with MIC value of 3.9 µg/mL against some of the tested bacterial strains. Compounds 6r and 6s consistently show promising minimum bactericidal concentration activity with MBC value of 7.8 µg/mL against Staphylococcus aureus MTCC 96 strain. Cytotoxic evaluation study claims that most of the compounds exhibit significant cytotoxicity against all the studied cancer cell lines. Particularly, compounds 6c, 6k, 6l, 6n and 6t against HeLa cell line and compounds 6c and 6h against B16-F10 cell line exhibit promising activities with IC50 values ranging from 6.34 to 9.99 μM. Further, most of the compounds are non-toxic against Chinese hamster ovary cell (CHO-K1) normal cell

Synthesis and cytotoxic evaluation of undecenoic acid-based oxime esters

1015-1022A series of undecenoic acid-based aldoxime esters have been synthesized using various substituted benzaldehydes and undecenoic acid. These oxime esters have been evaluated for their cytotoxic activities against HeLa, B16-F10, SKOV3, MCF7 and CHO-K1 normal cell line using MTT assay. Most of the synthesized compounds exhibit cytotoxicity. Particularly, 2,3-dimethoxy (IC50 value 12.48µM) and 3-methoxy (IC50 value 13.58µM) derivatives exhibit promising activities against SKOV3 cell lines. All the synthesized compounds are non-toxic towards the Chinese hamster ovary (CHO-K1) normal cell line