Preparation of Imidazolidin‐4‐ones and Their Evaluation as Hydrolytically Cleavable Precursors for the Slow Release of Bioactive Volatile Carbonyl Derivatives

Abstract

Imidazolidin-4-ones are suitable in practical applications as hydrolytically cleavable precursors for the controlled release of fragrant aldehydes and ketones. The corresponding profragrances were prepared by treating aliphatic carbonyl compounds with commercially available amino acid amines in the presence of a base to yield mixtures of diastereomers. The two diastereomers isolated from the reaction of glycinamide hydrochloride with (-)-menthone were separated by column chromatography. The absolute stereochemistry of the isomers was determined by NMR spectroscopy and confirmed by X-ray single crystal structure analysis. Under acidic conditions and in protic solvents, the two diastereomers slowly isomerized without releasing the ketone.

[3 + 2] Cycloaddition Reaction of in Situ Formed Azaoxyallyl Cations with Aldehydes: An Approach to Oxazolidin-4-ones

“…Because of their bioactivities and medicinal value, oxazolidin-4-ones have received increasing attention from organic and pharmaceutical chemists in the past few decades . Typical methods for the synthesis of oxazolidin-4-ones include cycloaddition reactions of oxaziridines with ketenes, azlactones, and ammonium enolates, photoelimination reactions of α-keto amides, domino O -alkylation/aza-Michael/retro-Claisen condensation reaction between enol ethers and α-bromoamido alcohols, and condensation reactions between α-hydroxyamides and carbonyl compounds in the presence of acids under heating conditions . Despite the fact that the aforementioned methods were of interest in constructing oxazolidin-4-ones, the development of a more efficient method with facile accessible substrates is still highly desirable.…”

Profragrances – Riechstoffvorstufen

“…Carbonylverbindungen können beispielsweise durch Hydrolyse von Heterozyklen freigesetzt werden. Verschiedene 1,3-heterozyklische Verbindungen, etwa Ace- tale [15,16] Oxazolidine [17][18][19], Imidazolidine (Aminale) [20,21] oder Imidazolidinone [22] (Abbildung 5), sind deshalb als Riechstoffvorstufen getestet worden. Die Wahl der Heteroatome sowie das Substitutionsmuster am Substrat spielen eine wichtige Rolle zur Beeinflussung der Hydrolysegeschwindigkeit.…”

“…relativ gute Ergebnisse erbrachten, haben sich andere Strukturen wie dimethylsubstituierte Diamine als weniger geeignet herausgestellt. Die strukturell verwandten Imidazolidinone (wie etwa 18, Abbildung 5) bilden unter den gegebenen Bedingungen keine dynamischen Gleichgewichte und funktionieren deshalb als "klassische", hydrolytisch spaltbare Riechstoffvorstufen [22].…”

Imidazolidinones and Imidazolidine‐2,4‐diones as Antiviral Agents

“…[21][22][23] Conventionally,2 -imidazolidinones and other cyclic ureas are synthesized by the reaction of diamines with several reagents such as carbonyldiimidazole, [24] trichloromethyl chloroformate, [25] organic carbonates, [26,27] dithiocarbonate, [28] carbonyl selenide, [29,30] and carbon monoxide (Scheme 1). [31,32] The reported methods for the synthesis of 4-imidazolidinones are reactiono fg lycinamide derivatives with carbonyl compounds under acidic [33,34] and basic [35,36] conditions (Scheme 2).…”