Synthesis of 3-amino-2-methyl/ethyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-d] pyrimidin-4(3H)-one and its Schiff bases as possible antimicrobial and non-steroidal antiinflammatory agents

摘要

Ethyl 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate 1 has been converted into ethyl 2-(acetylamino)-4,5,6,7-tetrahydro-l-benzothiophene-3-carboxylate 2a and ethyl 2-(propionylamino)-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate 2b.Compounds 2a and 2b on treatment with hydrazine hydrate give 3-amino-2-methyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrirnid-4(3H)-one 3a and 3-amino-2-ethyl-5,6,7,8-tetrahydro[l]benzothieno[2,3-d]pyrimid-4(3H)-one 3b respectively.Compounds 3a and 3b have been treated with aromatic aldehydes to get Schiff bases 4a-1 and 5a-1.The compounds have been characterized by spectral analysis and screened for antibacterial and antifungal activity.Eight compounds have also been screened for their antiinflammatory activity.A few of the compounds exhibit promising biological activity.