1956-15-6Relevant academic research and scientific papers
Bi-enzymatic Conversion of Cinnamic Acids to 2-Arylethylamines
Weise, Nicholas J.,Thapa, Prasansa,Ahmed, Syed T.,Heath, Rachel S.,Parmeggiani, Fabio,Turner, Nicholas J.,Flitsch, Sabine L.
, p. 995 - 998 (2020/01/21)
The conversion of carboxylic acids, such as acrylic acids, to amines is a transformation that remains challenging in synthetic organic chemistry. Despite the ubiquity of similar moieties in natural metabolic pathways, biocatalytic routes seem to have been overlooked for this purpose. Herein we present the conception and optimisation of a two-enzyme system, allowing the synthesis of β-phenylethylamine derivatives from readily-available ring-substituted cinnamic acids. After characterisation of both parts of the reaction in a two-step approach, a set of conditions allowing the one-pot biotransformation was optimised. This combination of a reversible deaminating and irreversible decarboxylating enzyme, both specific for the amino acid intermediate in tandem, represents a general method by which new strategies for the conversion of carboxylic acids to amines could be designed.
Organocatalytic Enantioselective Addition of α-Aminoalkyl Radicals to Isoquinolines
Liu, Xiangyuan,Liu, Yang,Chai, Guobi,Qiao, Baokun,Zhao, Xiaowei,Jiang, Zhiyong
supporting information, p. 6298 - 6301 (2018/10/09)
With a dual organocatalytic system involving a chiral phosphoric acid and a dicyanopyrazine-derived chromophore (DPZ) photosensitizer and under the irradiation with visible light, an enantioselective Minisci-type addition of α-amino acid-derived redox-active esters (RAEs) to isoquinolines has been developed. A variety of prochiral α-aminoalkyl radicals generated from RAEs were successfully introduced on isoquinolines, providing a range of valuable α-isoquinoline-substituted chiral secondary amines in high yields with good to excellent enantioselectivities.
Immunomodulatory peptides
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, (2014/12/12)
The invention relates to peptides derivatized with a hydrophilic polymer which, in some embodiments, bind to human FcRn and inhibit binding of the Fc portion of an IgG to an FcRn, thereby modulating serum IgG levels. The disclosed compositions and methods may be used in some embodiments, for example, in treating autoimmune diseases and inflammatory disorders. The invention also relates, in further embodiments, to methods of using and methods of making the peptides of the invention.
Phenylalanine ammonia lyase catalyzed synthesis of amino acids by an MIO-cofactor independent pathway
Lovelock, Sarah L.,Lloyd, Richard C.,Turner, Nicholas J.
supporting information, p. 4652 - 4656 (2014/05/20)
Phenylalanine ammonia lyases (PALs) belong to a family of 4-methylideneimidazole-5-one (MIO) cofactor dependent enzymes which are responsible for the conversion of L-phenylalanine into trans-cinnamic acid in eukaryotic and prokaryotic organisms. Under conditions of high ammonia concentration, this deamination reaction is reversible and hence there is considerable interest in the development of PALs as biocatalysts for the enantioselective synthesis of non-natural amino acids. Herein the discovery of a previously unobserved competing MIO-independent reaction pathway, which proceeds in a non-stereoselective manner and results in the generation of both L- and D-phenylalanine derivatives, is described. The mechanism of the MIO-independent pathway is explored through isotopic-labeling studies and mutagenesis of key active-site residues. The results obtained are consistent with amino acid deamination occurring by a stepwise E1cB elimination mechanism. All manner of things: A competing MIO-independent (MIO=4-methylideneimidazole-5-one) reaction pathway has been identified for phenylalanine ammonia lyases (PALs), which proceeds in a non-stereoselective manner, resulting in the generation of D-phenylalanine derivatives. The mechanism of D-amino acid formation is explored through isotopic-labeling studies and mutagenesis of key active-site residues.
Endothelin antagonist
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, (2008/06/13)
The instant invention relates to some tripeptide derivatives having activity against endothelin a process for preparing them, pharmaceutical composition containing the same and their use in prevention or treatment of some diseases associated with endothelin.
Enantioselective synthesis of non-natural amino acids using phenylalanine dehydrogenases modified by site-directed mutagenesis
Busca, Patricia,Paradisi, Francesca,Moynihan, Eamonn,Maguire, Anita R.,Engel, Paul C.
, p. 2684 - 2691 (2007/10/03)
The substrate scope of three mutants of phenylalanine dehydrogenase as biocatalysts for the transformation of a series of 2-oxo acids, structurally related to phenylpyruvic acid, to the analogous -amino acids, non-natural analogues of phenylalanine, has been investigated. The mutant enzymes are more tolerant than the wild type enzyme of the non-natural substrates, especially those with substituents at the 4-position on the phenyl ring. Excellent enantiocontrol resulted in all cases.
Alkylation of N′-[(S)-1′-phenylethyl]-N-(diphenylmethylene)glycinamide using a phase transfer catalyst (PTC) for practical asymmetric syntheses of α-amino acid derivatives
Kim, Hyun Ju,Lee, Sang-Kuk,Park, Yong Sun
, p. 613 - 616 (2007/10/03)
The chiral auxiliary mediated stereoselective alkylation reaction of N′-[(S)-1′-phenylethyl]-N-(diphenylmethylene)glycinamide (1) using a phase transfer catalyst (PTC) is described. Alkylation of 1 using 18-crown-6 as a PTC for liquid-solid extraction of KOH in toluene gives best results. This methodology provides a practical protocol for the preparation of a variety of enantio-enriched unnatural α-amino acid derivatives up to 83:17 enantiomeric ratio.
METABOLISM OF D,L-CHLORO-PHENYLALANINES BY PHENYLALANINE AMINOTRANSFERASE ISOZYMES PURIFIED FROM BUSHBEAN SHOOTS
Taylor, David C.,Wightman, Frank
, p. 1279 - 1288 (2007/10/02)
Key Word Index - Phaseolus vulgaris; Leguminosae; bushbean; metabolism; phenylalanine decarboxylase; phenylalanine aminotransferase; purification; substituted amino acids; D,L-chloro-phenylalanines.A series of mono-, di- and trichloro-D,L-phenylalanines was tested as substrates for both phenylalanine aminotransferase and phenylalanine decarboxylase partially purified from bushbean (Phaseolus vulgaris L.) seedling extracts by ammonium sulphate fractionation and Sephacryl S-300 gel filtration.While most of the D,L-chlorophenylalanines were transaminated at rates of 35-100percent of that observed with D,L-phenylalanine, no chloro-phenylalanine decarboxylase activity was observed.A transamination reaction is therefore likely to be the initial step in the conversion of chloro-phenylalanines to their corresponding chloro-phenylacetic acids via a reaction pathway similar to the known route for the metabolism of L-phenylalanine to phenylacetic acid.The highest specific activity of phenylalanine aminotransferase was found in both root and shoot tissues of bushbean at the 10-day stage of seedling growth.Partially purified extracts of these tissues were able to transaminate most of the mono- and dichloro-phenylalanines at ca 20-40percent of the rate observed with D,L-phenylalanine, while the trichloro-phenylalanines (assayed at lower concentrations due to solubility) were transaminated at rates equal to those observed with D,L-phenylalanine.The 4-chloro derivative was the best substrate tested showing rates of transamination that were 25percent higher than those observed with D,L-phenylalanine.Further purification of shoot fractions by DEAE-Sephacel chromatography resolved the phenylalanine aminotransferase activity into two peaks (enzymes I and II) which on further purification, were found to behave differently during hydrophobic chromatography and PAGE.These results indicated the presence of two isozymic forms of phenylalanine aminotransferase in bushbean shoots and both were found to catalyse transamination of the monochloro-phenylalanines examined in this study.
