Facile One-Pot Synthesis of Substituted Hydantoins from Carbamates

In 2017, researchers from the National Institute of Pharmaceutical Education and Research in India developed a simple and efficient method for synthesizing 3-substituted, 5-substituted, or 3,5-disubstituted hydantoins from carbamates. The process involved reacting a-amino methyl ester hydrochlorides with carbamates to produce ureido derivatives, which then cyclized under basic conditions to yield substituted hydantoins. This method was used to synthesize the anticonvulsant drug ethotoin, avoiding the use of hazardous reagents typically used in such syntheses. The procedure had a broad substrate scope and consistently produced good to excellent yields under mild conditions. The method was also applied in a gram-scale synthesis of Ethotoin, yielding a 78% success rate.