ビタミンB₁とその関連物質の物理化学的研究 (第8報)

ビタミンB₁塩酸塩の2変態の赤外部吸収スペクトルとその吸湿平衡について

抄録

Infrared spectra of the two kinds of polymorphic forms of thiamine hydrochloride were examined. The spectra showed difference in the absorption region (at 3μ and around 6μ) related to that of OH, NH₂, and NH₃⁺. Therefore, each was deuterated and the infrared spectra of deuterated derivatives were examined. It was concluded from this result that the β-forms formed a stronger hydrogen bond than the α-form, which suggested that there might be difference in their ability to absorb moisture. Measurement of the velocity and equilibrium of moisture absorption showed that the α-form absorbed moisture at a much faster rate and in a larger quantity than the β-form. In general, commercial thiamine hydrochloride found on the market recently is in α-form but β-form is also found at times. When stipulating the amount of moisture in thiamine hydrochloride, the value must differ with the α- and β-forms.