Rational designing of quinazolin-4(3H)-one based ALR2 inhibitors: Synthesis and biological evaluation

Abstract

Zenarestat withdrawal from the clinical trials owing to severe renal toxicity was a major setback in developing ALR2-targeted agents to manage diabetic complications. Addressing the toxicity issue by making some structural modifications in a well-known ALR2 inhibitor Zenarestat via a bioisosteric replacement/scaffold hopping approach can be very fruitful. This approach helps in obtaining a library of optimized analogues that can be potential ALR2 inhibitors with minimal side effect. Herein, using scaffold hoping, quinazolin-4(3H)-one was obtained as one of the top bioisostere with good BIF, shape and field scores. The designed in-house library of quinazolin-4(3H)-one was studied for their SAR profile based on the developed qualitative model via Activity atlas option. Important field points i.e., positive and negative electrostatics along with shape properties were analyzed that are crucial for ALR2 inhibitory activity. Some structure-based approaches including molecular docking and dynamics also suggested that the designed quinazolin-4(3H)-one based derivatives can be putative ALR2 inhibitors. These molecules were synthesized and evaluated for in-vitro ALR2 inhibitory activity. It was observed that compound Q2, Q3 and Q10 are most potent inhibitors with IC50 values of 2.56 ± 0.03, 1.72 ± 0.02 and 1.47 ± 0.03 µM, respectively. Additionally, the predicted ADMET properties were also found to be favorable in comparison to Zenarestat.