Synthesis and bacteriostatic activities of bis(Thiourea) derivatives with variable Chain Length

A series of 1,4-bis(decoxyphenyl)carbamothioyl-terephthalamide derivatives was successfully synthesised by reaction of benzene- 1,4-dicarbonyl isothiocyanate intermediates with long alkyl chain. the alkylation was performed via williamson etherification of 4-acetamidophenol with bromoalkanes.the synthesised bis(thiourea) derivatives differed in the chain length,cnh2n+1,where n = 10,12,and 14. the structures of all compounds were characterised by elemental chn analysis,ir,1h,and 13c nmr spectroscopies. bacteriostatic activities of bis(thiourea derivatives which consisted of two folds of n-h,c=o,and c=s and long alkyl chain substituents were carried out against gram-negative bacteria (escherichia coli,atcc 25922) via turbidimetric kinetic method. bis(thiourea) derivatives with n = 10 and n = 12 displayed excellent activity against e. coli with mic of 135 μg/ml and 145 μg/ml,respectively,while bis(thiourea) derivatives with n = 14 acted as cutoff point with no antibacterial properties. similar trend was observed in binding affinity to the active site of enoyl acp reductase (fabi),which demonstrated binding free energy of -5.3 kcal/mol and -4.9 and -4.8 kcal/mol,respectively. © 2016 a. n. abd halim and z. ngaini.