Synthesis and in vitro antibacterial activity of some N-(5-aryl-1,3,4-thiadiazole-2-yl)piperazinyl quinolone derivatives

• Published in: Farmaco (Società chimica italiana : 1989) 2003-10, Vol.58 (10), p.1023-1028
• Main Authors: Foroumadi, Alireza, Soltani, Fatemeh, Moshafi, Mohammad Hasan, Ashraf-Askari, Rogheeyeh
• Format: Article
• Language: English
• Subjects: Anti-Infective Agents - chemical synthesis; Anti-Infective Agents - pharmacology; Antibacterial activity; Antibacterial agents; Antibiotics. Antiinfectious agents. Antiparasitic agents; Biological and medical sciences; Gram-Negative Bacteria - drug effects; Gram-Positive Bacteria - drug effects; Medical sciences; Microbial Sensitivity Tests; Minimum inhibitory concentration; N-Piperazinyl quinolones; Pharmacology. Drug treatments; Piperazines - chemical synthesis; Quinolones - chemical synthesis; Quinolones - pharmacology; Staphylococcus aureus - drug effects; Staphylococcus epidermidis - drug effects; Structure-Activity Relationship; Thiadiazoles - chemical synthesis
• ISSN: 0014-827X; 1879-0569
• DOI: 10.1016/S0014-827X(03)00191-5

A series of N-[5-(1-methyl-5-nitro-2-imidazolyl)-1,3,4-thiadiazole-2-yl] and N-[5-(nitrophenyl)-1,3,4-thiadiazole-2-yl] piperazinyl quinolone derivatives ( 5a– c and 5d– l) were synthesized and evaluated for in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria. The antibacterial data revealed that all nitroimidazole derivatives ( 5a– c) showed interesting activity against tested Gram-positive bacteria (minimum inhibitory concentration, MIC=0.008–0.03 μg/ml) while they did not show good activity against Gram-negative organisms. Despite the significant activity of nitroimidazole series, all nitrophenyl analogues ( 5d– l) were inactive against both Gram-positive and Gram-negative bacteria. Among all of the tested compounds, 5a (ciprofloxacin derivative in nitroimidazole series) exhibited excellent activity against Staphylococcus aureus and Staphylococcus epidermidis (MIC=0.008 μg/ml).