Peculiar behavior of starch 2, 3-dialdehyde towards sulfanilamide and sulfathiazole. (5th November 2016) - Keshk, Sherif M.A.S.
Highlights: Synthesis of two novel Schiff's base. Difference in reactivity aldehyde starch and aldehyde cellulose towards Schiff base formation. Starch aldehyde reactivity comparison towards sulfanilamide and sulfathiazole. Abstract: In this study, starch (1 ) was oxidized to starch-2, 3-dialdehyde (DAS;2 ) using potassium periodate. In addition, two novel Schiff's bases (5 &6 ) were synthesized via a condensation reaction between DAS (2 ) and sulfa drugs (sulfanilamide;3 & sulfathiazole;4 ). The synthesized Schiff's bases (5 &6 ) were characterized by FT-IR spectroscopy, X-ray diffraction and DSC analysis. DAS can easily be oxidized owing to its high aldehyde content (91.0%). However, it has low reactivity towards sulfanilamide (3 ) and sulfathiazole (4). According to the diffraction functional theory, this peculiar behavior is caused by the absence of V-shape in α−glucan linkage in DAS molecules, making the carbonyl group least electropositive. This reduces the nucleophilic attacks of the amino group in sulfa drugs towards the carbonyl group in DAS.