Process for producing thiazole derivative

摘要

A process for producing a compound of formula (5) or a salt thereof:
[F18]
wherein the process is characterized by comprising reacting a compound of formula (1) or a salt thereof:
[F15]
with sulfur powder and cyanamide in the presence of a secondary amine, to thereby obtain a compound of formula (2) or a salt thereof:
[F16]
and reacting the obtained compound or a salt thereof hydrobromic acid and alkali metal nitrite, to thereby obtain a compound of formula (3) or a salt thereof:
F17]
and reacting the obtained compound or a salt thereof with alkyllithium and carbon dioxide.