Boehm, Ralf et al. published their patent in 1985 |CAS: 42518-42-3

The Article related to blood platelet aggregation inhibition thienopyrimidinediamine, thienopyrimidinediamine, benzothienopyrimidinediamine, aminolysis chlorothienopyrimidine, Heterocyclic Compounds (More Than One Hetero Atom): Pyrimidines and Quinazolines and other aspects.Quality Control of 2,4-Dichloro-5,6-dimethylthieno[2,3-d]pyrimidine

On September 4, 1985, Boehm, Ralf; Haubold, Gudrun; Pech, Reinhard; Laban, Gunter published a patent.Quality Control of 2,4-Dichloro-5,6-dimethylthieno[2,3-d]pyrimidine The title of the patent was Arylamino-substituted thieno[2,3-d]pyrimidines. And the patent contained the following:

Blood platelet aggregation inhibiting (no data) title compounds [I; R1 = R2 = Me; R1R2 = (CH2)4; R3 = R5 = H; R4 = R6 = aryl; R5R6N = saturated, monocyclic heterocydyl] were prepared by aminolysis of 2,4-dichlorothieno[2,3-d]pyrimidines. Thus, 2,4-dichloro-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidine was refluxed 6 h with 2-MeC6H4NH2 in PrOH to give 2-o-toluidino derivative II (R7 = Cl). This was refluxed with morpholine to give II (R7 = morpholino). The experimental process involved the reaction of 2,4-Dichloro-5,6-dimethylthieno[2,3-d]pyrimidine(cas: 42518-42-3).Quality Control of 2,4-Dichloro-5,6-dimethylthieno[2,3-d]pyrimidine

The Article related to blood platelet aggregation inhibition thienopyrimidinediamine, thienopyrimidinediamine, benzothienopyrimidinediamine, aminolysis chlorothienopyrimidine, Heterocyclic Compounds (More Than One Hetero Atom): Pyrimidines and Quinazolines and other aspects.Quality Control of 2,4-Dichloro-5,6-dimethylthieno[2,3-d]pyrimidine

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia