126400-95-1Relevant articles and documents
Mimicking enzymatic transaminations: Attempts to understand and develop a catalytic asymmetric approach to chiral α-amino acids
Bachmann, Stephan,Knudsen, Kristian Rahbek,Jorgensen, Karl Anker
, p. 2044 - 2049 (2004)
Attempts are made to build a bridge between asymmetric catalysis and enzymatic reactions by mechanistic investigations and the development of a catalytic and enantioselective approach to amination of α-keto esters by primary amines catalyzed by chiral Lewis acids as a model for transamination enzymes. Different Lewis acids can catalyze the half-transamination of α-keto esters using primary amine nitrogen sources such as pyridoxamine and 4-picolylamine. The mechanistic studies of the Lewis-acid catalyzed half-transamination using deuterium-labelled compounds show the incorporation of deuterium atoms in several positions of the α-amino acid derivative, indicating that the enol of the α-keto ester plays an important role along the reaction path. The catalytic enantioselective reactions are dependent on the pKa-value of the solvent since enantioselectivities were only obtained in solvents with high pKa-values relative to methanol. However, stronger acidic conditions generally gave better yields, but poor enantioselectivities. A series of chiral Lewis acids were screened as catalysts for the enantioselective half-transamination reactions and moderate yields and enantioselectivities of up to 46% ee were obtained.
Development of triazine-based esterifying reagents containing pyridines as a nucleophilic catalyst
Yamada, Kohei,Liu, Jie,Kunishima, Munetaka
supporting information, p. 6569 - 6575 (2018/09/25)
We have developed new triazine-based esterifying reagents comprising pyridines that can act as a nucleophilic catalyst. 1-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-3,5-lutidinium chloride (DMT-3,5-LUT) was found to exhibit a superior reactivity for the dehydrating condensation reaction between carboxylic acids and alcohols. The reaction of DMT-3,5-LUT with carboxylic acids produces intermediacy of acyloxytriazines, which is known to exhibit moderate reactivity toward alcohols, with concomitant liberation of 3,5-lutidine. The subsequent chemical transformation of the acyloxytriazines and alcohols into esters can be accelerated by the action of 3,5-lutidine as a nucleophilic catalyst. The detailed reaction mechanism revealed by a time-course analysis of the reactions is also discussed.
Efficient near infrared fluorescence detection of elastase enzyme using peptide-bound unsymmetrical squaraine dye
Saikiran, Maryala,Sato, Daisuke,Pandey, Shyam S.,Hayase, Shuzi,Kato, Tamaki
supporting information, p. 4024 - 4029 (2017/08/23)
Extended wavelength analyte-responsive fluorescent probes are highly desired for the imaging applications owing to their deep tissue penetration, and minimum interference from autofluorescence by biomolecules. Near infra-red (NIR) sensitive and self-quenching fluorescent probe based on the dye-peptide conjugate (SQ 1 PC) was designed and synthesized by facile and efficient one-pot synthetic route for the detection of Elastase activity. In the phosphate buffer solution, there was an efficient quenching of fluorescence of SQ 1 PC (86%) assisted by pronounced dye-dye interaction due to H-aggregate formation. Efficient and fast recovery of this quenched fluorescence of SQ 1 PC (> 50% in 30 s) was observed on hydrolysis of this peptide-dye conjugate by elastase enzyme. Presently designed NIR sensitive self-quenching substrate offers the potential application for the detection of diseases related to proteases by efficient and fast detection of their activities.
