Aminopyrazolo[1,5-a]pyrimidines as potential inhibitors of Mycobacterium tuberculosis: Structure activity relationships and ADME characterization.
Soares de Melo C, Feng TS, van der Westhuyzen R, Gessner RK, Street LJ, Morgans GL, Warner DF, Moosa A, Naran K, Lawrence N, Boshoff HI, Barry CE, Harris CJ, Gordon R, Chibale K.
Whole-cell high-throughput screening of a diverse SoftFocus library against Mycobacterium tuberculosis (Mtb) generated a novel aminopyrazolo[1,5-a]pyrimidine hit series. The synthesis and structure activity relationship studies identified compounds with potent antimycobacterial activity. The SAR of over 140 compounds shows that the 2-pyridylmethylamine moiety at the C-7 position of the pyrazolopyrimidine scaffold was important for Mtb activity, whereas the C-3 position offered a higher degree of flexibility. The series was also profiled for in vitro cytotoxicity and microsomal metabolic stability as well as physicochemical properties. Consequently liabilities to be addressed in a future lead optimization campaign have been identified.