Thiazolo[3,2-a]pyrimidin-5-one derivatives as a novel class of 11β-hydroxysteroid dehydrogenase inhibitors.

11β-hydroxysteroid type 1 dehydrogenase (11β-HSD1) is an enzyme that increases tissue concentrations of cortisol. Selective inhibitors of this enzyme regulate the level of cortisol and thus play a key role in the treatment of Cushing's syndrome, metabolic syndrome and type 2 diabetes. In this study the inhibitory activity of 29 thiazolo[3,2-a]pyrimidin-5-one derivatives on 11β-HSD1 were investigated. Studies were carried out with pooled human liver microsomes. A lot of analyzed compounds show activity for inhibiting 11β-HSD1 (up to 59.15% at concentration 10 µmol/l). Molecular docking simulation show that the molecule of the most active compound: 7-(cyclohexylmethyl)-2-iodomethyl-2,3-dihydrothiazolo[3,2-a]pyrimidin-5-one forms hydrogen bonds with Ala172, Leu171, Leu215 or Tyr177. In addition, the cycloalkane moiety can create the hydrophobic contacts with NADP+. For this compound also the most favourable Docking Score value was obtained. The most active compound only in the slight degree inhibits 11β-HSD2 activity and is a selective inhibitor of 11β-hydroxysteroid dehydrogenase type 1. Consequently it can have a real effect on the regulation of the cortisol level in the body.