BASIC ortho-ALKOXYPHENYLCARBAMIC ACID ESTERS CONTAINING VARIOUSLY SUBSTITUTED N-PHENYLPIPERAZINE FRAGMENT AND THEIR ANTIMICROBIAL ACTIVITY

Basic esters of ortho-alkoxyphenylcarbamic acid containing 4-(2-fluoro-/4-fluoro-/3-trifluoromethylphenyl)-piperazin-1-yl, 5a-8b, were screened for their in vitro antimicrobial activity against Escherichia coli, Candida albicans and Staphylococcus aureus, respectively. Following the minimum inhibitory concentration (MIC) assay, electronic and hydrophobic interactions, induced by suitable substitution at the N-phenylpiperazine ring, have appeared to be more notable factors which positively influenced the efficiency of such compounds against E. coli than the rising of their lipophilicity. Molecules comprising only of single atom of fluorine, 5a-6b, were observed to be more active (MIC=0.39-0.78 mg times mL super(-1)) in the comparison to those with trifluromethyl group (MICs>1.00 mg times mL super(-1)). On the contrary, the lipophilicity increasing of evaluated molecules accompanied by the presence of the substituent at N-phenylpiperazine with electron-withdrawing effect, 8a-8b, has positively reflected in their efficiency against C. albicans with the observed maximum of MIC=0.78 mg times mL super(-1). However, all tested molecules were against S. aureus (MICs>1.00 mg times mL super(-1)) practically inactive.