Synthesis and antiallergy activity of 10-oxo-10H-pyrido[1,2-a]thieno[3,2-d]pyrimidines and 10-oxo-10H-pyrido[1,2-a]thieno[3,4-d]pyrimidines

Article abstract of DOI:10.1021/jm00370a016

Synthesis and antiallergy activity of 10-oxo-10H-pyrido[1,2-a]thieno[3,2-d]pyrimidines and 10-oxo-10H-pyrido[1,2-a]thieno[3,4-d]pyrimidines are described. The activity, shown by these compounds in the rat passive cutaneous anaphylaxis (PCA) test, is compared to the PCA data previously reported for a series of 4-oxo-4H-pyrido[1,2-a]thieno[2,3-d]pyrimidines. 10-Oxo-N-1H-tetrazol-5-yl-10H-pyrido[1,2-a]thieno[3,4-d]pyrimidine, 10-oxo-7-(1H-tetrazol-5-yl)-10H-pyrido[1,2-a]thieno[2.3-d]pyrimidine, and 3,10-dihydro-10-oxo-7-(1H-tetrazol-5-yl)-1H-pyrido[1,2-a]thieno[3,4-d]pyri midine gave a 100% inhibition in the rat PCA test at a dose of 5 mg/kg. The activity displayed by these compounds is comparable to that of the most active compounds in the 4-oxo-4H-pyrido-[1,2-a]thieno[2,3-d]pyrimidine series.