Simple and effective purification of a SGLT-2 inhibitor cocrystal Rongliflozin l-pyroglutamic acid: coformer-induced purification

Abstract

Rongliflozin L-pyroglutamic acid, a highly active SGLT-2 inhibitor cocrystal discovered and developed by our group, is currently undergoing clinical trials for the treatment of diabetes. Here, we report and design a simple and robust process to obtain a single and pure crystalline form I (1) of the cocrystal, containing Rongliflozin (2) with L-pyroglutamic acid (L-PA), based on coformer-induced purification (CoIP). Extensive experiments showed that the addition of L-pyroglutamic acid in the eluent was key to suppression of the dissociation equilibrium of the cocrystal during lessivation, with high efficiency. Importantly, based in this profile, this process exhibited strong robustness and margin of safety at multigram and multikilogram scales.