ビタミンB_6-N-オキシドの研究 : (II)Pyridoxal phosphateおよびPyridoxamine phosphateのN-オキシドの調製

抄録

The coenzyme forms of vitamin B_6 N-oxide, pyridoxal phosphate N-oxide and pyridoxamine phosphate N-oxide, were obtained as follows : Pyridoxal N-oxide was phosphorylated with P_2O_5 and H_3PO_4 after its aldehyde group was protected by p-toluidine. After hydrolysis of its poly-esters, the resulted Schiff base monophosphate dissolved in 2NNaOH and p-toluidine was removed with ether. The solution was neutralized and poured onto a column of Dowex 50X8 in its H^+ form. The yellow fractions (absorption maximum : 390mμ) were collected and concentrated to a minimum solution, from which pyridoxal phosphate N-oxide was crystallized. Pyridoxamine phosphate N-oxide was easily prepared from pyridoxamine N-oxide as follows : After phosphorylation and hydrolysis of poly-esters, the reaction mixture was concentrated to a minimum syrup which was mixed with absolute ethanol. The white precipitate was collected and dissolved in pyridine・water and the crystal of pyridoxamine phosphate N-oxide was obtained by adding acetone.