625111-97-9Relevant articles and documents
Preparation method of racemic ketoisoleucine calcium and intermediate thereof
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Paragraph 0030; 0032; 0034; 0036; 0038; 0040, (2021/12/07)
The invention relates to a preparation method of racemic ketoisoleucine calcium and an intermediate thereof, the method comprises the following steps: reacting hydantoin and butanone in ammonia water to obtain sec-butyl hydantoin, adding strong base for reaction, and obtaining racemic ketoisoleucine salt with high yield and high purity without complex post-treatment steps. Calcium racemization ketoisoleucine can be prepared by using the calcium racemization ketoisoleucine salt prepared by the method, high-yield and high-purity calcium racemization ketoisoleucine can be obtained, the reaction solvent can be recycled and reused, the method is green and environment-friendly, and the problem of pollution to the environment is solved.
Dibutylphosphate (DBP) mediated synthesis of cyclic N,N′- disubstituted urea derivatives from amino esters: A comparative study
Agrawal, Sumit K.,Sathe, Manisha,Kaushik, M. P.,Halve, A. K.
, p. 5996 - 5999,4 (2020/08/20)
The N,N′-disubstituted urea derivatives such as amino acid hydantoins and dihydrouracil derivatives were prepared starting from natural and unnatural amino acid esters using dibutylphosphate (DBP). During the attempted synthesis of N-heterocycles with larger than six-membered rings containing the N,N′-disubstituted urea functionalities, three unexpected products namely squamolone, N-methyl pyrrolidine-2-one, and diketopiperazine were isolated.
Preparation of α-aminothioamides from aldehydes
Paventi, Martino,Edward, John T.
, p. 282 - 289 (2007/10/02)
The conversion of aldehydes into α-aminonitriles and thence into imidazolidin-4-thiones has been studied.Hydrolysis of the appropriate imidazolidin-4-thiones gave thioamides of nine naturally occuring α-amino acids.The possible pre-biotic significance of these compounds is discussed.