SELEXIPAG interMediate

4-[(5,6-Diphenyl-2-pyrazinyl)(1-methylethyl)amino]-1-butanol is a diphenylpyrazine derivative which belongs to a class of prostacyclin receptor agonists. It is an impurity of Selexipag (S253150) that is a potential drug for the treatment of various vascular disorders such as pulmonary arterial hypertension and arteriosclerosis obliterans.

Selexipag interMediate is a synthetic organic compound that is used as an intermediate in the synthesis of oxychloride. It is an oxychloride with a nucleophilic substitution reaction. The reaction proceeds selectively at the phosphorus atom and gives high yield. The reactivity of 4-[(5,6-diphenylpyrazin-2-yl)(propan-2-yl)amino]butan-1-ol is enhanced by the use of n butanol, which also acts as a solvent for the reaction. The product can be purified by filtration or recrystallization from hexane with piperazine as a reagent.