thiourea and potassium-hydroxide

Non-derivatizing, high-efficiency and low-toxicity solvents are important for studying the dissolution behavior and potential applications of starch. In this study, we investigated the starch dissolution mechanism and molecular conformation in KOH/thiourea aqueous solutions and compared these with KOH/urea and KOH aqueous solutions. Solubility analysis revealed that the KOH/thiourea solution demonstrates a better ability to dissolve corn starch than KOH/urea and KOH solutions. Rheological behavior and dynamic and static light scattering indicated that starch is stable in KOH/thiourea solution and exists as a regular star structure. Fourier transform infrared spectroscopy,

Topics: Carbohydrate Conformation; Carbon-13 Magnetic Resonance Spectroscopy; Hydrogen Bonding; Hydroxides; Molecular Dynamics Simulation; Potassium Compounds; Rheology; Solubility; Solvents; Spectroscopy, Fourier Transform Infrared; Starch; Thiourea; Water

To obtain a rapid, efficient and mild synthesis of 5,5-diphenylhydantoin and 5,5-diphenyl-2-thiohydantoin derivatives, ultrasonic irradiation has been applied to the reaction mixtures containing substituted benzils and urea or thiourea derivatives catalyzed by KOH in DMSO/H(2)O, which allowed us to achieve products at room temperature in a good yield and short time without any side product. This convenient procedure will allow a further increase of the diversity within the hydantoin family.

Topics: Catalysis; Dimethyl Sulfoxide; Hydroxides; Kinetics; Phenytoin; Potassium Compounds; Thiohydantoins; Thiourea; Ultrasonics; Water