Discovery and analgesic evaluation of 8-chloro-1,4-dihydropyrido[2,3- b ]pyrazine-2,3-dione as a novel potent d -amino acid oxidase inhibitor

Tilting the Scales toward EGFR Mutant Selectivity: Expanding the Scope of Bivalent "Type V" Kinase Inhibitors

Binding multiple sites within proteins with bivalent compounds is a strategy for developing uniquely active agents. A new class of dual-site inhibitors has emerged targeting the epidermal growth factor receptor (EGFR) anchored to both the orthosteric (ATP) and allosteric sites. Despite proof-of-concept successes, enabling selectivity against oncogenic activating mutations has not been achieved and classifying these inhibitors among kinase inhibitors remains underexplored. This study investigates the structure-activity relationships, binding modes, and biological activity of ATP-allosteric bivalent inhibitors (AABIs). We find that AABIs selectively inhibit drug-resistant EGFR mutants (L858R/T790M and L858R/T790M/C797S) by anchoring a methyl isoindolinone moiety along the αC-helix channel of the allosteric site. In contrast, related Type I1/2 inhibitors target wild-type EGFR but are less effective against resistant mutants. This shift in selectivity demonstrates that mutant-selective AABIs classify as "Type V" bivalent inhibitors.

Evolution of D-amino acid oxidase inhibitors: From concept to clinic

D-amino acid oxidase (DAAO) is a flavin-dependent peroxisomal monooxygenase with a substrate preference for glycine and certain small hydrophobic D-amino acids. Although the biochemical properties of the enzyme have been extensively studied since 1930s, the therapeutic interest in targeting the enzyme emerged more recently after the physiological significance of endogenous D-serine, a substrate for DAAO, was recognized in 1990s. This triggered a new wave of efforts by many researchers to develop more potent and drug-like DAAO inhibitors with greater translational potential. This chapter recounts the evolution of DAAO inhibitors since then driven by new molecular design strategies guided by structural biology. Some of these inhibitors were investigated in a range of preclinical in vivo studies to assess pharmacokinetics, pharmacodynamics, and behavioral pharmacology. Most importantly, these efforts culminated with the discovery of TAK-831 (luvadaxistat), an orally available brain-penetrant DAAO inhibitor currently under clinical development, representing a true bench-to-bedside success in this field.

Directing Group Enables Electrochemical Selectively Meta-Bromination of Pyridines under Mild Conditions

Without the use of catalysts and oxidants, a facile and sustainable electrochemical bromination protocol was developed. By introducing the directing groups, the regioselectivity of pyridine derivatives could be controlled at the meta-position utilizing the inexpensive and safe bromine salts at room temperature. A variety of brominated pyridine derivatives were obtained in 28-95% yields, and the reaction could be readily performed at a gram scale. By combining the installation and removing the directing group, the concept of meta-bromination of pyridines could be verified.