2-Methyl-5,7-dihydrothieno(3,4-d)pyrimidine 36267-71-7 5,7-Dihydro-2-methylthieno(3,4-d)pyrimidine EINECS 252-940-8 FEMA No. 3338 Thieno(3,4-d)pyrimidine, 5,7-dihydro-2-methyl-