29588-88-3Relevant articles and documents
Synthesis of new amides based on N-Phthaloyl-α-Amino Acids
Tukhtaev,Yusupov,Vinogradova
, p. 3049 - 3058 (2021/05/28)
N-phthaloyl derivatives of aliphatic α-amino acids were synthesized using phthalanhydride under standard conditions. The optimization reaction carried out by the thermal method to obtain the amides of these N-phthaloyl amino acids resulted in transimitted rather than amidation. The target amides of N-phthaloyl-α-amino acids were obtained by acylation of the amine with the corresponding acid chloroanhydrides in dichloromethane. These results were compared with the results of a similar acylation in a non-polar solvent (benzene). The dependence of the direction of the reaction on the duration of the acylation and the amount of amine used was established. The conditions for the formation of the corresponding N-phthaloyl-α-amino acid amides and asymmetric phthalic acid diamides were found. It is noteworthy that the formation of diamides is directly proportional to the equivalent amount of amine and the duration of the reaction, which makes it possible to purposefully control the synthesis in one reactor.
Chiral sensors for determining the absolute configurations of α-amino acid derivatives
Chen, Zhongxiang,Fan, Hongjun,Yang, Shiwei,Bian, Guangling,Song, Ling
, p. 6933 - 6939 (2018/10/02)
A simple strategy for configurational assignments of alpha-amino acids has been developed by comparison of the proton NMR chemical shift values of the alpha hydrogens of N-phthaloyl protected alpha-amino acids in the presence of (R)-CSA 1 and (S)-CSA 1, respectively. Highly resolved NMR spectra can be obtained directly on the mixed solution of the chiral solvating agents with N-phthaloyl protected alpha-amino acids in NMR tubes, giving well distinguishable proton signals without interference which dramatically improve the accuracy of assignment and hasten the assigning procedure. The strategy is widely applicable for varied natural and non-natural amino acids.
Enantiomerically Pure [2.2]Paracyclophane-4-thiol: A Planar Chiral Sulfur-Based Building Block Readily Available by Resolution with an Amino Acid Chiral Auxiliary
Vincent, Adrien,Deschamps, Damien,Martzel, Thomas,Lohier, Jean-Fran?ois,Richards, Christopher J.,Gaumont, Annie-Claude,Perrio, Stéphane
, p. 3961 - 3966 (2016/05/24)
Acyl chloride of N-phthaloyl-(S)-isoleucine is an efficient chiral auxiliary for the resolution of (±)-[2.2]paracyclophane-4-thiol. A preparative protocol, based on the conversion into diastereoisomeric thiolesters and separation by two fractional crystallizations and column chromatography, was developed. Deprotection with LiAlH4 allowed isolation of the individual thiol enantiomers in good yield (~40%) and high enantiomeric purity (ee >93%). The absolute configurations were determined by comparison of the optical rotation value of the products with literature data and were confirmed by X-ray crystallography.