The Reaction of S-Aminomethylthiamine with Acid Anhydride : The Synthesis of O, S-Bis (α-aminoacyl) thiamine

It was found that the reaction of S-aminomethylthiamine (II) with acid anhydride afforded the corresponding S-acylthiamine (III) or, O, S-diacylthiamine (IV). Furthermore the reaction of II with anhydrides (VII, IX, XII) of N-benzyloxycarbonyl-or N-t-butyloxycarbonyl-L-amino acid in tetrahydrofuran at -5-5° gave successfully the novel thiamine compounds with amino acid residues : O, S-bis (α-N-benzyloxycarbonyl-aminoacyl) thiamine (VIII) or O, S-bis (α-N-t-butyloxycarbonylaminoacyl) thiamine (X). O, S-Bis (α-aminoacyl) thiamine trihydrochloride (XI·3HCl) was obtained in good yield by the treatment of X with hydrogen chloride in ethyl acetate at -10°. Thiamine activities of VIII·HCl and XI·3HCl in thiamine deficient rats were similar to those of equimolar thiamine chloride hydrochloride (I-Cl·HCl).