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

•We synthetized three series of imidazo[1,2-b]pyrazoles.•39 of the synthetized products were evaluated for in vitro anticancer activity.•4 displayed an IC50 ≤ 10 μM in the 6 cell lines analyzed.•Some preliminary conclusions have been drawn from the SAR analysis.

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 IC50 ≤ 10 μM in the 6 cell lines analyzed (compounds 4d, 4g, 9a, 11a). A structure activity relationship analysis is also reported in this paper.

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