Strategic use of conformational bias and structure based design to identify potent JAK3 inhibitors with improved selectivity against the JAK family and the kinome
Using a structure based design approach we have identified a series of indazole substituted pyrrolopyrazines, which are potent inhibitors of JAK3. Intramolecular electronic repulsion was used as a strategy to induce a strong conformational bias within the ligand. Compounds bearing this conformation participated in a favorable hydrophobic interaction with a cysteine residue in the JAK3 binding pocket, which imparted high selectivity versus the kinome and improved selectivity within the JAK family.
Synthesis of 3-indazolecarboxylic esters and amides via Pd-catalyzed carbonylation of 3-iodoindazoles
A straightforward and effective procedure for the preparation of 1H-indazole-3-carboxylic acid esters and amides was developed. A series of functionalized 3-iodoindazoles were subjected to Pd-catalyzed carbonylations in the presence of methanol or amines,