Abstract
Thiamine mononitrate (Ib) was easily decomposed in methanol solution to produce crystalline compound (X') and 5-(2-hydroxyethyl)-4-methylthiazole (III). The structure of this compound (X') was presumed to be pentamethi (1, 4-dihydro-4-imino-2-methyl)-pyrimidinylen-1, 5-amer nitrate (IIc) from spectral and chemical data, and this was confirmed by the synthesis of 9-amino-2, 7, 10-trimethyl-5H-dipyrimido [1, 6-α : 4', 5'-d] pyrimidine derived from IIc. Compound (X), which was produced by the decomposition of thiamine monochloride (Ia) in methanol, is the hydrochloride of a base in IIc. IIc in aqueous solution reacted with acidic sodium sulfite to give 4-amino-2-methylpyrimidinyl-5-methanesulfonic acid (IX), and with III to give Ib.
