Synthesis of novel chiral TBBt derivatives with hydroxyl moiety. Studies on inhibition of human protein kinase CK2α and cytotoxicity properties

Abstract

The efficient method for the synthesis of novel 4,5,6,7-tetrabromo-1H-benzotriazole (TBBt) derivatives bearing a single stereogenic center has been developed. New compounds with a variety of substituents at the meta- and para-position of the phenyl ring are reported. All of the presented compounds were obtained using classical synthetic methods, such as bromination of benzotriazole, and its subsequent alkylation by monotosylated arylpropane-1,3-diols, which in turn have been synthesized through reduction of the corresponding prochiral β-keto esters, and the selective monotosylation of the primary hydroxyl group. The influence of the new and previously reported N-hydroxyalkyl TBBt derivatives on the activity of human protein kinase CK2α catalytic subunit was examined. The most active were derivatives with N-hydroxyalkyl substituents (IC50 in 0.80-7.35 μM range). A binding mode of (R)-1-(4,5,6,7-tetrabromo-2H-benzotriazol-2-yl)butan-3-ol 7b to hCK2α has been proposed based on in silico docking studies. Additionally, MTT-based cytotoxicity tests demonstrated high activities of novel 1-aryl-3-TBBt-propan-1-ol and 3-TBBt-propan-1,2-diol derivatives against human peripheral blood T lymphoblast (CCRF-CEM), and moderate anti-tumor activities against human breast adenocarcinoma (MCF7) cell lines.

Keywords: 4,5,6,7-Tetrabromo-1H-benzotriazole; Anti-tumor therapies; Cytotoxicity evaluations; Inhibitors; Molecular docking; Protein kinase CK2.