Synthesis, Spectral Characterization and Antimicrobial Activity of Substituted Thiazolyl Derivatives of 2-Quinolones

Abstract

A series of new 3-(2-substituted amino/substituted hydrazino-1,3-thiazol-4-yl)-4-hydroxy-1-methyl/phenylquinolin-2 (1H)-one hydroiodide 3a-3f and 4a-4f derivatives were prepared by heating 3-Acetyl-4-hydroxy-1-methyl/phenyl quinolin-2 (1H)-one 2a-2b with substituted thiourea and substituted thiosemicarbazide in presence of iodine in n-butanol. The title compounds were characterized on the basis of IR, 1H NMR, 13C NMR and Mass spectral (MS) studies. Further title compounds were evaluated for antibacterial and antifungal by Agar diffusion assay method where as antitubercular activity by Micro-plate Alamar Blue Assay (MABA). Among 12 synthesized novel compounds 3a, 3b, 4d exhibited promising antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. 3a, 3b, 3e, 4d, 4e showed good antifungal activity against Candida albicans and Aspergillus niger. 3a, 3d, 4d showed good antitubercular activity against Mycobacterium tuberculosis H37Rv strain.

In vitro Controlled Release from Solid Pharmaceutical Formulations of two new Adamantane Aminoethers with Antitubercular Activity (I).

“…Many strains of tuberculosis resist to the drugs mostly used to treat the disease and as a result new drugs and regimens are urgently needed to shorten the required duration of tuberculosis treatment [2][3][4][5][6]. N-Adamantan-2-yl-N'-[(E)-3,7-dimethylocta-2, 6dienyl]ethane-1,2-diamine (SQ109, ▶ Fig. 1), is a drug candidate that is active against both drug-susceptible and drug-resistant TB strains and affects cell wall synthesis [7].…”

Quinolone derivatives and their antifungal activities: An overview

“…2‐Quinolone‐thiazole hybrids 2 and 3 (Figure ) demonstrated potential antifungal activities against A. niger and C. albicans with MIC of 25–100 μg/ml, but they were less potent than the reference fluconazole (MIC: 12.5 μg/ml) . The SAR revealed that the introduction of substituted phenyl groups at thiazole fragment (R 2 ) could not improve the activity, and hybrids with –MePh at thiazole motif were less active than the analogs with –ClPh.…”

“…[35,36] 2-Quinolone-thiazole hybrids 2 and 3 ( Figure 3) demonstrated potential antifungal activities against A. niger and C. albicans with MIC of 25-100 μg/ml, but they were less potent than the reference fluconazole (MIC: 12.5 μg/ml). [37] The SAR revealed that the introduction of substituted phenyl groups at thiazole fragment (R 2 ) could not improve the activity, and hybrids with -MePh at thiazole motif were less active than the analogs with -ClPh. Replacement of -Me at N-1 position of 2-quinolone moiety by the phenyl group could enhance the activity to some extent, and the hydrazone compounds 3 were more active than the corresponding amine derivatives 2 generally.…”

Synthesis and Antimicrobial Activity of Novel 4-Hydroxy-2-quinolone Analogs

“…In the search for a new scaffold for antimicrobial drugs, 4-hydroxy-2-quinolone, a class of heterocyclic compound, has shown great potential, as various analogs of 4-hydroxy-2-quinolone including Roquinimex (Linomide), a synthetic immunomodulator [ 3 ], have been reported to possess a wide range of biological activities such as antibacterial [ 4 ], antifungal [ 5 ], anticancer [ 6 ], antioxidant [ 7 ], and so on. Over the past few decades, several attempts have been made to investigate the structure–activity relationship of the antimicrobial activity of this scaffold; for instance, the derivatives of 4-hydroxy-2-quinolone bearing chalcones [ 8 ], pyrimidines [ 9 ], pyrazoles [ 10 ], and thiadiazole [ 11 ] ( Figure 1 a).…”