Studies of Crystalline Vitamin B₁. XI. Presence of Quaternary Nitrogen¹

Abstract

Vol. 57Dihydrocerin (Cerinol).-One and one-half grams of cerin in 100 ml. of «-amyl alcohol was reduced by adding 3 g. of sodium to the hot solution over a period of fifteen minutes. After the sodium had dissolved completely, the alcohol was removed by steam distillation and the product recrystallized from dioxane. The dicarbinol, for which we propose the name cerinol, crystallized from dioxane in narrow white laths, which melted at 293-295°;[<& +9-4 (C = 0.48).

Effect of pH and form of the vitamin on its rate of destruction

“…The chemical properties of thiamine in relation to pH have been reviewed by Dwivedi and Arnold (1972). Williams and Ruehle (1935) first described the unusual behavior of thiamine chloride hydrochloride and other thiamine salts when titrated with base. The first step in this titration, with pK1 at about 4.8, represents the titration of the protonated amino pyrimidine group (Structure I > II, Fig.…”

Kinetics of Thiamine Hydrolysis

“…The vitamin undergoes several transformations under conditions of increasing pH. Williams (14) found, when titrating thiamine chloride hydrochloride with base, that after one mole equivalent of base, the p H did not continue t o rise rapidly on further addition. T h e addition of two more mole equivalents of base were required for complete neutralization.…”

Metabolic Fate and Mechanism of Action of Chloroethylthiamine

“…4-B), thiamine anhydride d) The effect of pH on the formal charge of the metabolite ... The formal charge of thia mine varies from +2 to neutral with increasing pH of the solution (13,14). As shown in Fig.…”