N′-(Arylsulfonyl)pyrazoline-1-carboxamidines as Novel, Neutral 5-Hydroxytryptamine 6 Receptor (5-HT6R) Antagonists with Unique Structural Features

Autor: Cor G de Korte, Stefan Verhoog, Martina A.W. van der Neut, Wouter I. Iwema Bakker, Alice J.M. Borst, Jennifer Venhorst, Chris G. Kruse, Natasja de Bruin, Rob P. van de Woestijne, Hiskias G. Keizer, Arnold van Loevezijn, Wouter de Looff, Jan-Willem van Wees, Maria J.P. van Dongen, Martijn van Hoeve
Rok vydání: 2011
Předmět:
Zdroj: Journal of Medicinal Chemistry. 54:7030-7054
ISSN: 1520-4804
0022-2623
Popis: The 5-HT(6) receptor (5-HT(6)R) has been in the spotlight for several years regarding CNS-related diseases. We set out to discover novel, neutral 5-HT(6)R antagonists to improve off-target selectivity compared to basic amine-containing scaffolds dominating the field. High-throughput screening identified the N'-(sulfonyl)pyrazoline-1-carboxamidine scaffold as a promising neutral core for starting hit-to-lead. Medicinal chemistry, molecular modeling, small molecule NMR and X-ray crystallography were subsequently applied to optimize the leads into antagonists (compounds 1-49) displaying high 5-HT(6)R affinity with optimal off-target selectivity. Unique structural features include a pseudoaromatic system and an internal hydrogen bond freezing the bioactive conformation. While physicochemical properties and CNS availability were generally favorable, significant efforts had to be made to improve metabolic stability. The optimized structure 42 is an extremely selective, hERG-free, high-affinity 5-HT(6)R antagonist showing good human in vitro metabolic stability. Rat pharmacokinetic data were sufficiently good to enable further in vivo profiling.
Databáze: OpenAIRE