Synthesis and biological evaluation of , a compound originally described as and an inhibitor of the anti-apoptotic protein Mcl-1

The development of inhibitors of anti-apoptotic proteins, such as Mcl-1, is currently a very active area in the field of cancer research. One of the very first reported inhibitors of Mcl-1 was the MIM1 molecule, but we have recently demonstrated that the structure of this compound had to be revised from 2 to the derivative 1 (FJ-809). In this paper we first develop a strategy to unambiguously prepare molecules such as 1 with a thiazol-3(2H)-yl)imino core, instead of the [2(3H)-thiazolylidene]hydrazine previously found in MIM1 (2). Next a series of biological studies have been performed on 1, using IGROV1-R10 ovarian cancer cells as models, and they have been complemented by fluorescence polarisation assays. These studies demonstrated that the new compound FJ-809(1) was devoid of any significant activity on Mcl-1, in contrast to 2. Then molecular modelling and molecular dynamics studies have been performed in order to elucidate the differences between FJ-809 and MIM1 in their interaction with the Mcl-1 protein.