93019-08-0Relevant academic research and scientific papers
Ammonolysis of morpholine-2,5-diones: Participation of the primary amide group. Part 2
Arcelli, Antonio,Bongini, Alessandro,Porzi, Gianni,Rinaldi, Samuele
, p. 132 - 141 (2012/05/04)
The ammonolysis of three morpholine-2,5-dione derivatives was investigated and the mechanism ascertained by kinetic studies and theoretical calculations. The kinetics, followed by high-performance liquid chromatography analysis, evidenced the presence of two intermediates, which were isolated and characterized. The ammonolysis occurs with a complex mechanism involving two consecutive reactions followed by two parallel ones. The second step of the whole reaction involves an anchimeric assistance of the primary amide group. The pseudo-first-order rate constants were calculated by appropriate equations, which describe the single steps of the process. Computational density functional theory investigations of vicinal primary amide group participation were performed using a model compound, and the transition states were generated. The theoretical calculations evidenced the essential role exerted by ammonia, which acts as a proton transfer.
Synthesis of conformationally constrained amino acid and peptide derivatives
Bailey,Bannister,Bernad,Blanchard,Boa
, p. 3245 - 3251 (2007/10/03)
6-Benzylpiperazine-2,3,5-trione 5, a cyclic phenylalanine derivative, can be selectively and sequentially alkylated at N4, C6 and N1 to provide a range of conformationally constrained phenylalanine mimetics. Alkylation at C6, the α-carbon of the phenylalanine moiety is achieved under mild conditions and gives rise to Phe derivatives posessing a dialkylated α-carbon. Alkylation of piperazine 5 using methyl bromoacetate and ethyl bromopropionate gives access to peptoids 7 and 21 which are conformationally contrained Phe-Gly and Phe-Ala analogues respectively. The X-ray crystal structure of triallylated derivative 17 is also reported.
