ML351 is a potent and highly specific 15-LOX-1 inhibitor with an IC50 of 200 nM. ML351 shows excellent selectivity (>250-fold) versus the related isozymes, 5-LOX, platelet 12-LOX, 15-LOX-2, ovine COX-1, and human COX-2. ML351 prevents dysglycemia and reduces β-cell oxidative stress in nonobese diabetic mouse model of T1D.