UK-315716/UK-240455. Pfizer.

Pfizer is developing the atropoisomeric quinoxalinediones, UK-315716 and UK-240255, from a series of NMDA/glycine antagonists for the potential treatment of stroke. Both are compounds are undergoing clinical trials. UK-315716 has improved aqueous solubility and in vivo efficacy over UK-240455, and a lower projected clinical dose of 200 mg compared to 500 mg with UK-240455.