Reactions with 2-hydrazinobenzothieno-pyrimidinone: synthesis of benozthienotriazolopyrimidines

ABSTRACT

The material used in this work was 2-hydrazino-5,6,7,8-tetrahydro- benzothieno [2,3-d] pyrimidine-4[3H] one 1. So, compound 1 reacted with some electrophiles, such as formic acid or carbon disulfide to yield 1,2,4-triazalo [4,3-a] pyrimidine derivatives 2 and 3, respectively. Treatment of compound 1 with the proper aldehydes led to formation of the corresponding hydrazones 4, which cyclized and spontaneously aromatized into 5. Furthermore, photooxidation of some derivatives with the same system was studied