Synthesis of 2-{2-[(α/β-naphthalen-1-ylsulfonyl)amino]-1,3-thiazol-4-yl} acetamides with 11β-hydroxysteroid dehydrogenase inhibition and in combo antidiabetic activities

Compounds 1-10 were designed using a bioisosteric approach and were prepared using a short synthetic route. The in vitro inhibitory activity of the compounds against 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) was evaluated. Compounds 5 (α-series) and 10 (β-series) had a moderate inhibitory enzyme activity (55.26% and 67.03% inhibition at 10 μM, respectively) and were as active as BVT.14225 (positive control). Both compounds have a piperidine ring in their structure, but the most active (10) was selected to establish its in vivo antidiabetic effect using a non insulin-dependent diabetes mellitus rat model. The antidiabetic activity of compound 10 was determined at 50 mg/kg single dose in an acute model, and also by short term sub-chronic administration for 5 days. The results indicated a significant decrease of plasma glucose levels, similar than BVT.14225. Additionally, a molecular docking of the most active compounds of each series into the ligand binding pocket of one subunit of human 11β-HSD1 was performed. In this model the oxygen atom of the sulfonamide make hydrogen bond interactions with the catalytic residues Ser170 and Ala172. We also observed important π-π interactions between the naphthyl group and Tyr177.