Identification of 3-aminomethyl-1,2-dihydro-4-phenyl-1-isoquinolones: A new class of potent, selective, and orally active non-peptide dipeptidyl peptidase IV inhibitors that form a unique interaction with Lys554

Synthesis, inhibition of dipeptidyl peptidase IV (DPP-4) inhibitory activity of new isoquinolone (35a) are described.