Abstract
The coenzyme forms of vitamin B_6 analogues containing 2-hydroxymethyl group instead of 2-methyl group (designated as ω-hydroxy PAL-P and ω-hydroxy-PAM-P were obtained as follows : (1) Transformation from acetylated PAM-N-oxide into ω-hydroxy-PAM (I) by refuxing in acetic anhydride solution, followed by hydrolysis with HCl・ethanol. (2) Phosphorylation of I with P_2O_5 and H_3PO_4, followed by treatment with hot water in order to hydrolyze resulting polyphosphate and purification by column chromatography with Amberlite CG-50. Crystallization of ω-hydroxy PAM-P (II) in colorless needles (mp. 135-137℃). (3) Conversion of II to ω-hydroxy PAL-P (III) by transamination using pyridine-2-aldehyde in nitrogen atmosphere at room temperature. Purification by Dowex 50X8 column chromatography. Pale yellow crystals (mp. 94-96℃ (decomp.)). The structures of II and III were confirmed by their absorption spectra in the absence and presence of borate ion, IR- and NMR- spectra and the results of other tests.