Studies on 5H-pyrimidothiazines. Part I. Synthesis of 6- and 7-carboxyalkyl derivatives of 5H-pyrimido[4,5-b][1,4]thiazine was written by Duro, F.;Santagati, N. A.;Scapini, G.. And the article was included in Farmaco, Edizione Scientifica in 1978.Formula: C4H5N3O This article mentions the following:
Primidothiazines I (R = H, R1 = CO2Me; R = Me, Ph, R1 = CO2Et; R = CO2Et, R1 = H) were obtained by treating 4-mercapto-5-aminopyrimidine (II) with HCOCHClCO2Me, AcCHClCO2Et, BzCHClCO2Et, or BrCH2COCO2Et resp. I (R = CO2Et, R1 = H) was hydrolyzed to the acid. Reaction of I (R = Ph, R1 = CO2Et) with N2H4 gave the pyrazolone III, which was cleaved by N2H4 to II and 3-phenyl-3-pyrazoline-5-one. Reaction of II with BzCHClCO2Et in the presence of NaOMe gave the ester IV, which was hydrolyzed to the acid and cyclized by HOAc to 5H-pyrimido[4,5-b][1,4]thiazin-6(7H)-one. In the experiment, the researchers used many compounds, for example, 5-Aminopyrimidin-4(3H)-one (cas: 69785-94-0Formula: C4H5N3O).
5-Aminopyrimidin-4(3H)-one (cas: 69785-94-0) belongs to pyrimidine derivatives. Pyrimidine is an aromatic heterocyclic organic compound similar to pyridine. Pyrimidine derivatives also play an important role in drug development, either in concert with other compounds or on their own.Formula: C4H5N3O
Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia