Diastereomeric Salt Resolution Based Synthesis of LY503430, an AMPA (α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid) Potentiator

This article describes the development and optimization of chemical reactions and subsequent preparation of the API LY503430 under cGMPs to fund first human dose (FHD) clinical evaluation as a potential therapeutic agent for Parkinson's disease. Reasons and rationale are presented for changes in solvents and reagents. One of the major developments presented here is the replacement of a chiral chromatography with a diastereomeric salt resolution. This article also discusses a preferred orientation issue with LY503430 which complicated the XRPD analysis.