Pyrimidine, C4H4N2, itself is a water-soluble base which melts at 21° C. and possesses a narcotic smell.
Pyridine gives origin to: pyridazine or ortho-diazine, pyrimidine or metadiazine, pyrazine or para-diazine, osotriazine, unsymmetrical triazine, symmetrical triazine, osotetrazone and tetrazine.
Its hydrochloride melts at 163° C., and crystallizes from alcohol in colourless deliquescent prisms. Acetic anhydride converts the base into an acetamino-dimethyl pyrimidine, acetic acid and acetamide being also formed.
It condenses with acetic anhydride to form a methyldiphenyl triazine, acetamide being also formed; with acetyl-acetone to form dimethylphenyl pyrimidine (A.