Scale-Up and Development of a One-Step Process for the Synthesis of Succinylcholine

Succinylcholine chloride is a neuromuscular blocking agent identified as an essential medicine by the World Health Organization. This article describes a practical synthesis and scale-up of this active pharmaceutical ingredient (API) from readily available starting materials. Analytical methods were developed to identify and quantify impurities in the API. In addition, process development resulted in practical isolation and purification procedures, which avoid the need for a recrystallization step. The process has been scaled up to 25 g reproducibly in three batches, giving an average 89% overall yield and purity meeting USP and ICH guideline specifications for API-quality succinylcholine.