Synthesis and Antitubercular Activity of Oleanolic Acid Analogs

In continuation of our research work on development of potent antitubercular leads, nine analogs of oleanolic acid, a pentacyclic triterpenoid, were synthesized by exploring different motifs. Modification of the A-ring and C-17 acid group was carried out and the target compounds were obtained in good yield (45 – 90%). All synthesized compounds were screened for in vitro anti-tubercular activity against drug resistant Mycobacterium tuberculosis H37Rv, M. tuberculosis RifR, and M. bovis. In the present study, three compounds (3, 5 and 9) showed good activity against M. bovis, while oleanolic acid and other analogs exhibited weak activity against drug resistant strains. The compounds were non-toxic to rat and murine macrophage.