15504-42-4Relevant academic research and scientific papers
Characterization of N-methylated amino acids by GC-MS after ethyl chloroformate derivatization
Reddy, B. Sudarshana,Chary, V. Naresh,Pavankumar,Prabhakar
, p. 638 - 650 (2016)
Methylation is an essential metabolic process in the biological systems, and it is significant for several biological reactions in living organisms. Methylated compounds are known to be involved in most of the bodily functions, and some of them serve as biomarkers. Theoretically, all α-amino acids can be methylated, and it is possible to encounter them in most animal/plant samples. But the analytical data, especially the mass spectral data, are available only for a few of the methylated amino acids. Thus, it is essential to generate mass spectral data and to develop mass spectrometry methods for the identification of all possible methylated amino acids for future metabolomic studies. In this study, all N-methyl and N,N-dimethyl amino acids were synthesized by the methylation of α-amino acids and characterized by a GC-MS method. The methylated amino acids were derivatized with ethyl chloroformate and analyzed by GC-MS under EI and methane/CI conditions. The EI mass spectra of ethyl chloroformate derivatives of N-methyl (1–18) and N,N-dimethyl amino acids (19–35) showed abundant [M-COOC2H5]+ ions. The fragment ions due to loss of C2H4, CO2, (CO2 + C2H4) from [M-COOC2H5]+ were of structure indicative for 1–18. The EI spectra of 19–35 showed less number of fragment ions when compared with those of 1–18. The side chain group (R) caused specific fragment ions characteristic to its structure. The methane/CI spectra of the studied compounds showed [M + H]+ ions to substantiate their molecular weights. The detected EI fragment ions were characteristic of the structure that made easy identification of the studied compounds, including isomeric/isobaric compounds. Fragmentation patterns of the studied compounds (1–35) were confirmed by high-resolution mass spectra data and further substantiated by the data obtained from 13C2-labeled glycines and N-ethoxycarbonyl methoxy esters. The method was applied to human plasma samples for the identification of amino acids and methylated amino acids. Copyright
One-step synthesis of tertiary α-amino ketones and α-amino esters from amines and diazocarbonyl compounds
West,Glaeske,Naidu
, p. 977 - 980 (1993)
Diazoketones and diazoesters react with tertiary amines in the presence of copper powder to form transient ammonium ylides. These ylides undergo facile [1,2]-shift from N to C (Stevens rearrangement) of the best migrating group. Overall, α-substituted α-a
Tandem catalytic allylic amination and [2,3]-stevens rearrangement of tertiary amines
Soheili, Arash,Tambar, Uttam K.
supporting information; experimental part, p. 12956 - 12959 (2011/10/08)
We have developed a catalytic allylic amination involving tertiary aminoesters and allylcarbonates, which is the first example of the use of tertiary amines as intermolecular nucleophiles in metal-catalyzed allylic substitution chemistry. This process is
Generation and reaction of benzylammonium N-methylides with N-cyanomethyl or N-(ethoxycarbonylalkyl) groups
Zhang, Chen,Maeda, Yasuhiro,Shirai, Naohiro,Sato, Yoshiro
, p. 25 - 28 (2007/10/03)
N-Cyanomethyl-, N-ethoxycarbonylmethyl- and N-(3-ethoxycarbonylpropyl)-N-methylbenzylammonium N-methylides 6a,b and 22 have been generated by fluoride ion-induced desilylation of the corresponding N-(trimethylsilylmethyl)benzylammonium salts 5a,b and 21. Sommelet-Hauser 7, 23 and Stevens 8, 24 rearrangement products were obtained from 6a and 22, but not from 6b.
Use of Carboxylic Acids as Chiral Solvating Agents for the Determination of Optical Purity of Chiral Amines by NMR Spectroscopy
Benson, Scott C.,Cai, Ping,Colon, Marcelo,Haiza, Mohammed A.,Tokles, Maritherese,Snyder, John K.
, p. 5335 - 5341 (2007/10/02)
Optically pure mandelic acid, Mosher's acid, and N-(3,5-dinitrobenzoyl)phenylglycine have been used as chiral solvating agents to induce nonequivalence in the 1H NMR spectra of several diamines, amino acid esters, amino alcohols, and other amines.The identity of the chiral solvating agent and the stoichiometry of the solvation complexes that yield the greatest nonequivalence varies with the nature of the substrate.
THE REACTION OF DICHLOROCARBENE WITH β-ETHANOLAMINES. STEREOSPECIFIC SYNTHESIS OF EPOXIDES
Castedo, Luis,Castro, Jose L.,Riguera, Ricardo
, p. 1205 - 1208 (2007/10/02)
Optically pure β-ethanolamines were converted into epoxides in good yield and with high e.e. (>= 95percent) by reaction with dichlorocarbene.By this method α-aminoacids were successfully converted into synthetically useful epoxides.
