New imidazo[1,2-b]pyrazoles as anticancer agents: Synthesis, biological evaluation and structure activity relationship analysis

Abstract Synthesis and functionalization strategies of the imidazo[1,2- b ]pyrazole core were developed giving a rapid access to three series of novel imidazo[1,2- b ]pyrazole type derivatives: C-2/C-6/C-7 trisubstituted, C-2/C-3/C-6 tri(hetero)arylated and C-2/C-3/C-6/C-7 tetrasubstituted imidazo[1,2- b ]pyrazoles. 39 of the synthetized products were evaluated for in vitro anticancer activity using the MTT colorimetric assay against 5 human and 1 murine cancer cell lines. Promising in vitro growth inhibitory activities were exhibited by some of the target compounds. Of the 39 evaluated products, 4 displayed an IC 50  ≤ 10 μM in the 6 cell lines analyzed (compounds 4d , 4g , 9a , 11a ). A structure activity relationship analysis is also reported in this paper.