4 - ( 4 - Pyridine ) - 2 - mercapto - 1, 3 thiazole ( PTT ) is a intermediate of cephalosporin derivaties TAK-599, which synthetic process is first 2 - bromo - 1 -( 4 - pyridinyl ) - 1 - ethanone hydrobromide( BAP ) is prepared from 4 - acetyl pyridine and hydrogen bromide solution, then ADTC is obtained through adding carbon disulfide and ethyl acetate to BAP. Finally the product PTT was obtained through the neutralization reaction by sodium acetate. The synthetic process was optimized. PTT is prepared by the potimizing process, the product content is more than 99%, ADTC yield reaches 82%, PTT total yield reaches 66%.