634-97-9Relevant academic research and scientific papers
Identification and characterization of bifunctional proline racemase/hydroxyproline epimerase from archaea: Discrimination of substrates and molecular evolution
Watanabe, Seiya,Tanimoto, Yoshiaki,Nishiwaki, Hisashi,Watanabe, Yasuo
, (2015)
Proline racemase (ProR) is a member of the pyridoxal 5′-phosphate-independent racemase family, and is involved in the Stickland reaction (fermentation) in certain clostridia as well as the mechanisms underlying the escape of parasites fromhost immunity in eukaryotic Trypanosoma. Hydroxyproline epimerase (HypE), which is in the same protein family as ProR, catalyzes the first step of the trans-4-hydroxy-L-proline metabolism of bacteria. Their substrate specificities were previously considered to be very strict, in spite of similarities in their structures and catalytic mechanisms, and no racemase/epimerase fromthe ProR superfamily has been found in archaea.We here characterized the ProR-like protein (OCC-00372) from the hyperthermophilic archaeon, Thermococcus litoralis (TlProR). This protein could reversibly catalyze not only the racemization of proline, but also the epimerization of 4-hydroxyproline and 3-hydroxyproline with similar kinetic constants. Among the four (putative) ligand binding sites, one amino acid substitution was detected between TlProR (tryptophan at the position of 241) and natural ProR (phenylalanine). TheW241F mutant showed a significant preference for proline over hydroxyproline, suggesting that this (hydrophobic and bulky) tryptophan residue played an importance role in the recognition of hydroxyproline (more hydrophilic and bulky than proline), and substrate specificity for hydroxyproline was evolutionarily acquired separately between natural HypE and ProR. A phylogenetic analysis indicated that such unique broad substrate specificity was derived from an ancestral enzyme of this superfamily.
Minor constituents of Spigelia anthelmia and their cardiac activities
Huebner, Harald,Vierling, Wolfgang,Brandt, Wolfgang,Reiter, Melchior,Achenbach, Hans
, p. 285 - 296 (2001)
A more detailed phytochemical analysis of extracts of the aerial parts of Spigelia anthelmia L. (Loganiaceae) yielded 20 structurally related new compounds besides spiganthine and ryanodine. Structure elucidation was achieved mainly by spectroscopic methods. The compounds were tested on their cardiac and on their insect antifeedant activities.
Pyrrole-2-carboxylic acid and its dimers: Molecular structures and vibrational spectrum
Dubis, Alina T.,Grabowski, Slawomir J.,Romanowska, Dorota B.,Misiaszek, Tomasz,Leszczynski, Jerzy
, p. 10613 - 10621 (2002)
The infrared and Raman spectroscopic study of pyrrole-2-carboxylic acid (PCA) confirms the formation of the cyclic acid dimer species in the solid state. The molecular structure, vibrational frequencies, and binding energies of cyclic dimers have been also examined using the density functional theory (DFT) at the B3LYP/ 6-311+G(d) level. In addition, a complete vibrational assignment is proposed for the both s-cis and s-trans PCA conformers. The vibrational assignments are supported by normal coordinate calculations utilizing force constants predicted using the DFT method. The atoms in molecules theory of Bader is also used to characterize hydrogen bonds.
Conversion of pyrrole to pyrrole-2-carboxylate by cells of Bacillus megaterium in supercritical CO2
Matsuda,Ohashi,Harada,Yanagihara,Nagasawa,Nakamura
, p. 2194 - 2195 (2001)
Pyrrole was converted to pyrrole-2-carboxylate in supercritical CO2 using cells of Bacillus megaterium PYR 2910, and the yield of the carboxylation reaction in supercritical CO2 was 12 times higher than that under atmospheric pressur
Integrating Biomass into the Organonitrogen Chemical Supply Chain: Production of Pyrrole and d-Proline from Furfural
Di, Lu,Fung Kin Yuen, Vincent,Song, Song,Sun, Qiming,Yan, Ning,Zhou, Kang
supporting information, p. 19846 - 19850 (2020/09/02)
Production of renewable, high-value N-containing chemicals from lignocellulose will expand product diversity and increase the economic competitiveness of the biorefinery. Herein, we report a single-step conversion of furfural to pyrrole in 75 % yield as a key N-containing building block, achieved via tandem decarbonylation–amination reactions over tailor-designed Pd?S-1 and H-beta zeolite catalytic system. Pyrrole was further transformed into dl-proline in two steps following carboxylation with CO2 and hydrogenation over Rh/C catalyst. After treating with Escherichia coli, valuable d-proline was obtained in theoretically maximum yield (50 %) bearing 99 % ee. The report here establishes a route bridging commercial commodity feedstock from biomass with high-value organonitrogen chemicals through pyrrole as a hub molecule.
N,N-coordination Rh complex as well as synthesis method and application thereof
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Paragraph 0024; 0025; 0026, (2018/03/28)
The invention belongs to the technical field of synthesis of organic metal compounds and particularly relates to an N,N-coordination Rh complex as well as a synthesis method and an application thereof. Firstly, a ligand is synthesized from methyl 1H-pyrrole-2-carboxylate as an initial raw material and further reacts with Rh(COD)2Cl, and a metal complex with Rh as a central atom is obtained. The synthesis method is simple, the complex as a catalyst can be used for catalyzing a series of reductive amination reactions of derivatives of acetophenone and aniline, and the product yield is good and is 90% or above.
N, O-coordination mode rhodium complex and synthesis method and use thereof
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Paragraph 0019; 0020; 0021, (2017/08/31)
The invention belongs to the technical field of coordination chemistry, and in particular relates to an N, O-coordination mode rhodium complex and a synthesis method and use thereof. The central atom of the N, O-coordination mode rhodium complex is rhodium (Rh). The N, O-coordination mode rhodium complex is prepared by synthesis of a ligand by use of 1H-pyrrole-2-carboxylate as a starting material and further effect of the ligand and Rh (COD) 2BF4, and the N, O-coordination mode rhodium complex can be used as an acetophenone derivative reduction reaction catalyst. The N, O-coordination mode rhodium complex has the advantages of simple synthesis process, better selectivity and yield. The catalytic activity of the N, O-coordination mode rhodium complex as the catalyst is high.
Vanadium(v) oxoanions in basic water solution: A simple oxidative system for the one pot selective conversion of l-proline to pyrroline-2-carboxylate
Biancalana, Lorenzo,Tuci, Giada,Piccinelli, Fabio,Marchetti, Fabio,Bortoluzzi, Marco,Pampaloni, Guido
, p. 15059 - 15069 (2017/11/14)
The unprecedented, direct chemical oxidation of l-proline to pyrroline-2-carboxylate was achieved in water (pH 9-10) by means of NH4VO3/NH3 or V2O5/MOH (K = Na, K), and the anion was fully characterized as ammonium or alkaline metal salts. Quantitative yield and higher atom economy performance were achieved with the latter system, the alkaline salts being more stable than the ammonium one. Different mixed valence V(iv)/V(v) compounds precipitated from the reaction mixtures depending on the nature of the employed base. A possible reaction mechanism is proposed according to DFT calculations. The analogous reaction of trans-4-hydroxy-l-proline with NH4VO3/NH3 afforded pyrrole-2-carboxylic acid in 81% yield, while sarcosine underwent prevalent decomposition under similar experimental conditions. Instead, no reaction was observed with primary (glycine, l-alanine, l-phenylalanine) and tertiary α-amino acids (N,N-dimethyl-l-phenylalanine, N,N-dimethylglycine).
The pyrrolecarboxylic acid production
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Paragraph 0047; 0048; 0049; 0050, (2017/09/02)
PROBLEM TO BE SOLVED: To provide a novel production method of pyrrole carboxylic acids, with which carbon dioxide can be utilized as a carbon source and a pyrrole carboxylic acid useful as a production raw material of medicines and agrochemicals is easily produced by making 1H-pyrrole react with carbon dioxide so that a carboxy group is directly introduced into a pyrrole skeleton in a low pressure of 1 MPa or less.SOLUTION: In introducing a carboxy group into a pyrrole skeleton by directly carboxylating 1H-pyrrole with carbon dioxide in a reaction solvent and in the presence of a catalyst, an excess of basic catalyst over 1H-pyrrole is used as the catalyst so that a pyrrole carboxylic acid is produced by introducing a carboxy group into a pyrrole skeleton in a low pressure of 1 MPa or less. The basic catalyst is lithium t-butoxide.
[NO]- and [NN]-coordination mode rhodium complexes based on a flexible ligand: Synthesis, reactivity and catalytic activity
Yao, Zi-Jian,Li, Kuan,Zhang, Jian-Yong,Deng, Wei
, p. 8753 - 8759 (2016/10/13)
A flexible [NON]-type ligand was prepared via a stepwise method. Air- and moisture-stable LL- (N,O-coordination mode) (1) and LX-type (N,N-coordination mode) (2) rhodium(i) complexes were synthesized based on this flexible ligand under different reaction conditions. The two rhodium complexes were isolated in good yields and characterized by elemental analysis and IR and NMR spectrometry. The molecular structures of complexes 1 and 2 were confirmed by single-crystal X-ray analysis. The cationic rhodium complex was shown to be a good catalyst for the hydrogenation of acetophenone derivatives without pre-dried solvents and reagents. Good efficiency was achieved for a series of substrates with either electron-donating or electron-withdrawing groups.
