[EN] PYRAZOLOPYRIDINE DERIVATIVE HAVING GLP-1 RECEPTOR AGONIST EFFECT<br/>[FR] DÉRIVÉ DE PYRAZOLOPYRIDINE AYANT UN EFFET AGONISTE DU RÉCEPTEUR GLP-1<br/>[JA] GLP-1受容体アゴニスト作用を持つピラゾロピリジン誘導体
stable orthoquinone monoketals, and thus constitutes a valuable alternative to the use of chemical oxidants that are often based on toxic metallic species. The propionic acid derivatives are initially converted into O-spirolactonic quinonebisketals that are then selectively hydrolyzed into the desired monoketal compounds. In the absence of blocking substituents, orthoquinone monoketals spontaneously undergo