Synthesis and Biological Evaluation of Thieno[3,2-d]- pyrimidinones, Thieno[3,2-d]pyrimidines and Quinazolinones: Conformationally Restricted 17b-Hydroxysteroid Dehydrogenase Type 2 (17b-HSD2) Inhibitors

In this study, a series of conformationally restricted thieno[3,2-d]pyrimidinones, thieno[3,2-d]pyrimidines and quinazolinones was designed and synthesized with the goal of improving the biological activity as 17-hydroxysteroid dehydrogenase type 2 inhibitors of the corresponding amidothiophene derivatives. Two moderately active compounds were discovered and this allowed the identification of the biologically active open conformer as well as the extension of the enzyme binding site characterisation

Hydroxybenzothiazoles as New Nonsteroidal Inhibitors of 17β-Hydroxysteroid Dehydrogenase Type 1 (17β-HSD1)

17β-estradiol (E2), the most potent estrogen in humans, known to be involved in the development and progession of estrogen-dependent diseases (EDD) like breast cancer and endometriosis. 17β-HSD1, which catalyses the reduction of the weak estrogen estrone (E1) to E2, is often overexpressed in breast cancer and endometriotic tissues. An inhibition of 17β-HSD1 could selectively reduce the local E2-level thus allowing for a novel, targeted approach in the treatment of EDD. Continuing our search for new nonsteroidal 17β-HSD1 inhibitors, a novel pharmacophore model was derived from crystallographic data and used for the virtual screening of a small library of compounds. Subsequent experimental verification of the virtual hits led to the identification of the moderately active compound 5. Rigidification and further structure modifications resulted in the discovery of a novel class of 17β-HSD1 inhibitors bearing a benzothiazole-scaffold linked to a phenyl ring via keto- or amide-bridge. Their putative binding modes were investigated by correlating their biological data with features of the pharmacophore model. The most active keto-derivative 6 shows IC50-values in the nanomolar range for the transformation of E1 to E2 by 17β-HSD1, reasonable selectivity against 17β-HSD2 but pronounced affinity to the estrogen receptors (ERs). On the other hand, the best amide-derivative 21 shows only medium 17β-HSD1 inhibitory activity at the target enzyme as well as fair selectivity against 17β-HSD2 and ERs. The compounds 6 and 21 can be regarded as first benzothiazole-type 17β-HSD1 inhibitors for the development of potential therapeutics

Synthesis and Biological Evaluation of Thieno[3,2-d]- pyrimidinones, Thieno[3,2-d]pyrimidines and Quinazolinones: Conformationally Restricted 17b-Hydroxysteroid Dehydrogenase Type 2 (17b-HSD2) Inhibitors

In this study, a series of conformationally restricted thieno[3,2-d]pyrimidinones, thieno[3,2-d]pyrimidines and quinazolinones was designed and synthesized with the goal of improving the biological activity as 17b-hydroxysteroid dehydrogenase type 2 inhibitors of the corresponding amidothiophene derivatives. Two moderately active compounds were discovered and this allowed the identification of the biologically active open conformer as well as the extension of the enzyme binding site characterisation

Metabolic stability optimization and metabolite identification of 2,5-thiophene amide 17β-hydroxysteroid dehydrogenase type 2 inhibitors.

17β-HSD2 is a promising new target for the treatment of osteoporosis. In this paper, a rational strategy to overcome the metabolic liability in the 2,5-thiophene amide class of 17β-HSD2 inhibitors is described, and the biological activity of the new inhibitors. Applying different strategies, as lowering the cLogP or modifying the structures of the molecules, compounds 27, 31 and 35 with strongly improved metabolic stability were obtained. For understanding biotransformation in the 2,5-thiophene amide class the main metabolic pathways of three properly selected compounds were elucidated

Metabolic Stability Optimization and Metabolite Identification of 2,5-Thiophene Amide 17<beta>-Hydroxysteroid Dehydrogenase Type 2 Inhibitors

17β-HSD2 is a promising new target for the treatment of osteoporosis. In this paper, a rational strategy to overcome the metabolic liability in the 2,5-thiophene amide class of 17β-HSD2 inhibitors is described, and the biological activity of the new inhibitors. Applying different strategies, as lowering the cLogP or modifying the structures of the molecules, compounds 27, 31 and 35 with strongly improved metabolic stability were obtained. For understanding biotransformation in the 2,5-thiophene amide class the main metabolic pathways of three properly selected compounds were elucidated

CCDC 149914: Experimental Crystal Structure Determination

Related Article: S.Marchais, E.S.Vermeulen, G.Semple, S.Sundell, H.V.Wikstrom|2001|Anal.Chim.Acta|426|85|doi:10.1016/S0003-2670(00)01172-7,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Pharmacophoric features exploited by 6 and 21.

<p>Six for compound <b>6</b> (showed in A) and five for compound <b>21</b> (showed in B).</p