- Synthesis and reactivity of 5-methylenehydantoins
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5-Methylenehydantoin, as well as the N-mono- and N,N-di-protected derivatives, can be obtained by different synthetic routes. These compounds can undergo a large variety of reactions, such as Diels-Alder, epoxidation, methanol addition and conjugate addition reactions of different types of nucleophiles, including carbon (cyanide), nitrogen (piperidine) and sulfur (thiols, thioacetate) nucleophiles. The reactivity with electrophilic reagents, such as m-CPBA or methanol in acidic medium, and the need for Lewis acids to promote the conjugate addition reactions indicate that hydantoin is a poor electron-withdrawing group.
- Fraile, José M.,Lafuente, Gustavo,Mayoral, José A.,Pallarés, Antonio
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experimental part
p. 8639 - 8647
(2011/11/30)
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- Diethyl 2,4-Dioxoimidazolidine-5-phosphonates: Horner-Wadsworth-Emmons Reagents for the Mild and Efficient Preparation of C-5 Unsaturated Hydantoin Derivatives
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The phosphonates 19 and 20 were prepared from hydantoin and 1-methylhydantoin, respectively, by way of bromination at C-5 and a subsequent Michaelis-Arbuzov reaction with triethyl phosphite.The Horner-Wadsworth-Emmons-type reagents 19 and 20 were found to react readily with aromatic and aliphatic aldehydes, in the presence of a base, to produce C-5 unsaturated hydantoin derivatives 22 and 26, generally in high yield.The products 22 and 26 were frequently isolated as mixtures of E and Z isomers depending upon the identity of the aldehyde and phosphonate.The isomeric configuration of the products was determined from analysis of NMR spectral data.Long-range (13)C-(1)H coupling constants between the C-4 carbonyl of the hydantoin ring and the olefinic proton were found to be diagnostic of isomer geometry.Conditions were also developed that allowed coupling of 19 and 20 with cyclic and acyclic ketones and α-dicarbonyl compounds to afford the corresponding olefinic products.C-5 unsaturated hydantoin derivatives are of synthetic utility as precursors to α-amino acid derivatives, pyruvates, and the imidazoquinolin-2-one heterocyclic ring system, a class of potent inhibitors of low Km cAMP phosphodiesterase and the chromophore present in the siderophore azotobactin.
- Meanwell, Nicholas A.,Roth, Herbert R.,Smith, Edward C. R.,Wedding, Donald L.,Wright, J. J. Kim
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p. 6897 - 6904
(2007/10/02)
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- Process for production of hydantoin derivatives
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Hydantoin derivatives are industrially advantageously produced at a high yield by reacting hydantoin with carbonyl compounds in the presence of (i) amino acids or the salts thereof and (ii) inorganic alkali compounds for a relatively short reaction time in an aqueous medium.
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- Search for pro-drug forms of D-penicillamine: Synthesis and metabolism of D-pen-hydantoin.
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The existence of dihydropyrimidase possessing the ability to hydrolyse into hydantoic acids some hydantoins of D relative configuration has been pointed out in the literature. Owing to the identity of relative configuration between (R)-5-isopropylhydantoin and (S)-5(1-mercapto-1-methyl) ethylhydantoin (D-pen-hydantoin), the synthesis and metabolism study of the latter were undertaken to determine if D-penhydantoin could act as a pro-drug form of D-penicillamine. Various references compounds i.e. corresponding hydantoic acid, its disulfide and hydantoin disulfide were synthesized to perform a quantitative study of the metabolic profile of D-penhydantoin. The only metabolite detected in the urines of rat and rabbit was 5-isopropylidenehydantoin.
- Poupaert,Mukarugambwa,Dumont
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p. 511 - 514
(2007/10/02)
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- 5-Secondary alkylidene hydantoins
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A 5-Secondary alkylidene hydantoin having the formula STR1 in which: (a) R is an alkyl group having 1-2 carbon atoms; and (b) X is hydrogen or a phenyl group can be prepared by condensing a hydantoin having the formula STR2 and a ketone having the formula STR3 in the presence of ammonia or an amine catalyst, the amine being a primary amine having a pKb between about 3 and about 5.
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