4441-50-3Relevant academic research and scientific papers
Direct Synthesis of Free α-Amino Acids by Telescoping Three-Step Process from 1,2-Diols
Inada, Haruki,Shibuya, Masatoshi,Yamamoto, Yoshihiko
supporting information, p. 709 - 713 (2019/01/25)
A practical telescoping three-step process for the syntheses of α-amino acids from the corresponding 1,2-diols has been developed. This process enables the direct synthesis of free α-amino acids without any protection/deprotection step. This method was also effective for the preparation of a 15N-labeled α-amino acid. 1,2-Diols bearing α,β-unsaturated ester moieties afforded bicyclic α-amino acids through intramolecular [3 + 2] cycloadditions. A preliminary study suggests that the resultant α-amino acids are resolvable by aminoacylases with almost complete selectivity.
Efficient and Practical Arene Hydrogenation by Heterogeneous Catalysts under Mild Conditions
Maegawa, Tomohiro,Akashi, Akira,Yaguchi, Kiichiro,Iwasaki, Yohei,Shigetsura, Masahiro,Monguchi, Yasunari,Sajiki, Hironao
experimental part, p. 6953 - 6963 (2010/02/28)
An efficient and practical arene hydrogenation procedure based on the use of heterogeneous platinum group catalysts has been developed. Rh/C is the most effective catalyst for the hydrogenation of the aromatic ring, which can be conducted in iPrOH under neutral conditions and at ordinary to medium H 2 pressures (10 atm). A variety of arenes such as alkylbenzenes, benzoic acids, pyridines, furans, are hydrogenated to the corresponding cyclohexyl and heterocyclic compounds in good to excellet yields. The use of Ru/C, less expensive than Rh/C, affords an effective and practical method for the hydrogenation of arenes including phenols. Both catalysts can be reused several times after simple filtration without any significant loss of catalytic activity.
Self-association-free dimeric cinchona alkaloid organocatalysts: Unprecedented catalytic activity, enantioselectivity and catalyst recyclability in dynamic kinetic resolution of racemic azlactones
Woong Lee, Ji,Hi Ryu, Tae,Suk Oh, Joong,Yong Bae, Han,Bin Jang, Hyeong,Eui Song, Choong
supporting information; experimental part, p. 7224 - 7226 (2010/03/25)
Self-association-free, bifunctional, squaramide-based dimeric cinchona alkaloid organocatalysts show unprecedented catalytic activity, enantioselectivity and catalyst recyclability in the dynamic kinetic resolution (DKR) reaction of a broad range of racemic azlactones. The Royal Society of Chemistry 2009.
A mild and facile method for complete hydrogenation of aromatic nuclei in water
Maegawa, Tomohiro,Akashi, Akira,Sajiki, Hironao
, p. 1440 - 1442 (2007/10/03)
A mild and complete hydrogenation of aromatic rings catalyzed by heterogeneous 10% Rh/C proceeds at 80 °C in water under 5 atm of H 2 pressure. This method is applicable to the hydrogenation of various carbon and heteroaromatic compounds such as alkylbenzenes, biphenyls, pyridines and furans. Georg Thieme Verlag Stuttgart.
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.
New synthetic routes to α-amino acids and γ-oxygenated α-amino acids. Reductive denitration and oxidative transformations of γ-nitro-α-amino acids
Crossley, Maxwell J.,Fung, Yik M.,Kyriakopoulos, Efstathia,Potter, Jeffrey J.
, p. 1123 - 1130 (2007/10/03)
Transformation of γ-nitro-α-amino acid derivatives into α-amino acids by reductive denitration, into the γ-oxo-α-amino acids by ozonolysis of the corresponding amino acid ester nitronate derivatives, and into γ-hydroxy-α-amino acid derivatives by subsequent reduction of the oxo functionality, can be achieved in good yields. As the γ-nitro-α-amino acid derivatives are prepared from N,O-protected dehydroalanines derivable from the corresponding alanine, serine and cysteine derivatives by specific routes, the overall procedures provide a means for selective conversion of these simple α-amino acids into more complex ones.
Arylsulfonamide derivative and pharmaceutical compositions and use thereof
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, (2008/06/13)
An arylsulfonamide derivative of the formula (I): STR1 wherein R1 is unsubstituted phenyl or naphthyl, or phenyl substituted by 1 to 3 same or different substituents selected from the group consisting of halogen, alkyl, nitro and alkoxy, R2 is straight, branched, or branched cyclic alkyl with 1 to 15 carbon atoms, phenyl, phenyloxyl, phenyloxy substituted by one or more halogen atoms, cycloalkyl with 5 to 7 carbon atoms, indolyl, alkylthiol with 1 to 4 carbon atoms, hydroxyl, protected hydroxyl, imidazolyl, pyridyloxyl, or --OSO2 R4, R4 is straight or branched alkyl with 1 to 15 carbon atoms, or unsubstituted phenyl or thienyl, or phenyl or thienyl substituted by 1 to 3 same or different substituents of halogen, alkyl, nitro and alkoxy, R3 is hydrogen or straight or branched alkyl with 1 to 20 carbon atoms, n is an integer of 0 to 10, p is an integer of 0 to 10, X is a group of the formula m and q are independently an integer of 0 to 8, and A is a direct bond or phenylene, or a salt thereof; a process for manufacture thereof and a pharmaceutical composition containing same. The above compound exhibits thromboxane A2 antagonism.
Site-specific incorporation of non-natural residues into peptides: Effect of residue structure on suppression and translation efficiencies
Bain,Wacker, Dean A.,Kuo, Eric E.,Chamberlin, A. Richard
, p. 2389 - 2400 (2007/10/02)
A systematic survey of the structural requirements for biosynthetic incorporation of non-natural residues into a polypeptide is presented. Relative translation efficiencies for a series of 12 semi-synthetic acylated suppressor tRNAs ranged from 0 to 91% depending on the structure of the residue incorporated.
Process for preparing ACHPA
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, (2008/06/13)
Process comprising coupling of an acylimidazole-activated derivative of a reduced and protected phenylalanine with the magnesium salt of malonic acid monoethyl ester to produce the beta-ketoester, which is subsequently reduced with NaCNBH3 /THF in glacial acetic acid to afford a separable mixture of 3-S and 3-R 3-hydroxy-(4S)-4-(N-α-BOC)amino-5-cyclohexylpentanoic acid, such that large-scale, high yield production of optically-active ACHPA is significantly improved.
