Design, Synthesis, Characterisation and Evaluation of Thymydylate Synthase X (THYX)Inhibitors against Mycobacterium Tuberculosis.

Tuberculosis (TB) is an airborne, chronic, deadly bacterial infection caused by Mycobacterium tuberculosis (MTB), an aerobic bacilli belonging to the family Mycobacteriaceae, first identified in 1882 by Robert Koch, which affects the lungs _ Candidate molecules were designed based on HipHop (catalyst® software) and docked against Thymidylate Synthase X (ThyX) protein using Drug Design Software (Maestro 9.1). The SAR of high scoring molecules was studied and they are optimized based on the synthetic feasibility. Four compounds with high G score were shortlisted for the synthesis and they are labelled as M1, M2, M3, and M4. The structures of the compounds were assigned on the basis of IR, 1H NMR, 13C NMR, and MASS data. In-vitro Anti tubercular activity – The compounds were screened for antitubercular activity by Broth Micro dilution method. _ Of the four compounds M1 and M2 exhibited antitubercular activity; compound M1 exhibited minimum inhibition at 250μg/ml and M2 at 500μg/ml. The docking score of the candidates correlates with the invitro activity of the ligands. Toxicological evaluation - The results of acute toxicity studies have shown that the synthesized compounds are non toxic and did not induce any mortality at the highest OECD guideline dose 2000mg/kg. These compounds are attractive strong point to find newer lead compounds which will find ultimate use in the treatment of drug resistant tuberculosis. Further these compounds are tested for advanced antitubercular assays in in-vitro like Luciferase Reporter Phage Assay (LRP), Micro plate Alamar Blue Assay (MABA), Resazurin microtitre Assay (REMA), Serine/Threonine Protein (STP) Kinase Assay, BACTEC-TB system and In-vivo assay like Balb/C mouse model for CFU and mortality