Challenges in the development of an M 4 PAM preclinical candidate: The discovery, SAR, and biological characterization of a series of azetidine-derived tertiary amides
摘要:
Herein we describe the continued optimization of M-4 positive allosteric modulators (PAMs) within the 5-amino-thieno[2,3-c] pyridazine series of compounds. In this letter, we disclose our studies on tertiary amides derived from substituted azetidines. This series provided excellent CNS penetration, which had been challenging to consistently achieve in other amide series. Efforts to mitigate high clearance, aided by metabolic softspot analysis, were unsuccessful and precluded this series from further consideration as a preclinical candidate. In the course of this study, we found that potassium tetrafluoroborate salts could be engaged in a tosyl hydrazone reductive cross coupling reaction, a previously unreported transformation, which expands the synthetic utility of the methodology. (C) 2017 Elsevier Ltd. All rights reserved.
Merging Halogen-Atom Transfer (XAT) and Copper Catalysis for the Modular Suzuki–Miyaura-Type Cross-Coupling of Alkyl Iodides and Organoborons
作者:Zhenhua Zhang、Bartosz Górski、Daniele Leonori
DOI:10.1021/jacs.1c12649
日期:2022.2.2
Suzuki–Miyaura-type cross-couplings between alkyl iodides and aryl organoborons. This process requires a copper catalyst but, in contrast with previous approaches based on palladium and nickel systems, does not utilizes the metal for the activation of the alkylelectrophile. Instead, this strategy exploits the halogen-atom-transfer ability of α-aminoalkyl radicals to convert secondary alkyl iodides into the