Kexue Li

Discovery of pyrrolopyridazines as novel DGAT1 inhibitors.

A new structural class of DGAT1 inhibitors was discovered and the structure-activity relationship was explored. The pyrrolotriazine core of the original lead molecule was changed to a pyrrolopyridazine core providing an increase in potency. Further exploration resulted in optimization of the propyl group at C7 and the discovery that the ester at C6 could be replaced by five-membered heterocyclic rings. The analogs prepared have DGAT1 IC(50) values ranging from >10 μM to 48 nM.

Inhibiting NF-κB-inducing kinase (NIK): Discovery, structure-based design, synthesis, structure–activity relationship, and co-crystal structures

The discovery, structure-based design, synthesis, and optimization of NIK inhibitors are described. Our work began with an HTS hit, imidazopyridinyl pyrimidinamine 1. We utilized homology modeling and conformational analysis to optimize the indole scaffold leading to the discovery of novel and potent conformationally constrained inhibitors such as compounds 25 and 28. Compounds 25 and 31 were co-crystallized with NIK kinase domain to provide structural insights.

Discovery of 6-phenylpyrimido[4,5-b][1,4]oxazines as potent and selective acyl CoA:diacylglycerol acyltransferase 1 (DGAT1) inhibitors with in vivo efficacy in rodents.

The discovery and optimization of a series of acyl CoA:diacylglycerol acyltransferase 1 (DGAT1) inhibitors based on a pyrimido[4,5-b][1,4]oxazine scaffold is described. The SAR of a moderately potent HTS hit was investigated resulting in the discovery of phenylcyclohexylacetic acid 1, which displayed good DGAT1 inhibitory activity, selectivity, and PK properties. During preclinical toxicity studies a metabolite of 1 was observed that was responsible for elevating the levels of liver enzymes ALT and AST. Subsequently, analogues were synthesized to preclude the formation of the toxic metabolite. This effort resulted in the discovery of spiroindane 42, which displayed significantly improved DGAT1 inhibition compared to 1. Spiroindane 42 was well tolerated in rodents in vivo, demonstrated efficacy in an oral triglyceride uptake study in mice, and had an acceptable safety profile in preclinical toxicity studies.