WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF LOWER ALKYL HAVING FROM 1 TO 4 CARBON ATOMS AND ALLYL, FOR EXAMPLE, 4,6-DIMETHYL - 2 - N-PROPYLAMINOTHIAZOLO-(4,5-D)PYRIMIDINE 5,7,DIONE. THESE COMPOUNDS ARE USEFUL CENTRAL NERVOUS SYSTEM ANTI-DEPRESANTS.
WHEREIN R AND R'' ARE EACH INDEPENDENTLY SELECTED FROM THE GROUP CONSISTING OF LOWER ALKYL HAVING FROM 1 TO 3 CARBON ATOMS, ALLYL AND METHALLYL, AND THE PHARMACEUTICALLY ACCEPTABLE ACID SALTS THEREOF, FOR EXAMPLE, 1-ALLYL3-(2'',4''-DIKETO - 1'',2'',3'',4''-TETRAHYDROPYRIMIDIN-6-YL)-1'',2, 3''-TRIMETHYL-2-THIOPSEUDOUREA. THESE COMPOUNDS ARE USEFUL CENTRAL NERVOUS SYSTEM ANTI-DEPRESSANTS.