Compound 1a (NN414) is a potent opener of Kir6. 2/SUR1 K ATP channels. Compound 1a inhibits insulin release in vitro and in vivo and preserves beta cell function in preclinical animal models suggesting that such a compound could find use in treatment or prevention of type 1 and type 2 diabetes. The crystal structure and a convergent synthesis of 1a are presented together with a range of new analogues of 1a. Several compounds, eg, 6- ...