PYRIMIDINDERIVATE

The compounds of the general formula I (I) and pharmaceutically acceptable acid addition salts and hydrates thereof possess useful immunostimulant properties and can be used in therapy. In the general Formula I A stands for -CH2-CH2-, -CH2-CH2-CH2-, -CH2-CH2-CH2CH2-or -CH=CH-; R4 is hydrogen, C1-4 alkyl or optionally substituted phenyl; r is 0, 1, 2, 3 or 4; R1 stands for hydrogen of C1-5 alkanoyl; R2 represents hydrogen, C1-5 alkanoyl or a group of the general formula (a) (a) wherein R stands for hydrogen, C1-4 alkyl, C2-4 alkenyl, phenyl or phenyl-C1-3 alkyl and R3 stands for hydrogen. The compounds of the general Formula I can be prepared by reacting a 2-mercapto-4,6-diamino-pyrimidine of the general Formula II (II) with a dihalo compound of the general Formula III (III) (wherein Y and Z are halogen).