COMBINATION OF THE TOPLISS APPROACH WITH THE FREE-WILSON ANALYSIS IN THE STUDY OF ANTIMYCOBACTERIAL ACTIVITY OF 4-ALKYLTHIOBENZANILIDES

On the basis of a preliminary study of the antimycobacterial activity of thiobenzanilides, a group of 4'-isopropyl- and 4'-butylthiobenzanil ides have been synthesized and tested against Mycobacterium tuberculos is, Mycobacterium kansasii, Mycobacterium avium and Mycobacterium fort uitum. The effect of the substituents on minimum inhibitory concentrat ions was calculated by the Free-Wilson method. The separated values we re analyzed by the Topliss approach. The substitution of the thiobenza nilide in position 4' by the isopropyl group or butyl group increased the antimycobacterial activity less than the cyclohexyl group. The sub stitution in position 4 decreased the activity by the steric effect.