6485-67-2Relevant articles and documents
Hybrid catalysis of 8-quinolinecarboxaldehyde and br?nsted acid for efficient racemization of α-amino amides and its application in chemoenzymatic dynamic kinetic resolution
Kiyokawa, Mari,Nagato, Yuya,Ohmatsu, Kohsuke,Ooi, Takashi,Shirai, Yuto
, (2021/06/21)
The combination of 8-quinolinecarboxaldehyde and benzoic acid proved to be an effective catalyst system for the racemization of N-unprotected α-aryl- or α-alkyl-substituted α-amino amides. Application of this system to chemoenzymatic dynamic kinetic resolution provided an efficient access to enantiomerically pure N-acetyl-α-amino amides in good to high yields.
COMPLEMENT MODULATORS AND RELATED METHODS
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Paragraph 0422, (2020/10/20)
The present disclosure presents compounds and compositions that interact with complement components. Some compounds inhibit complement activity. Included are small molecule compounds and compositions that function as C5 inhibitor compounds. Methods for inhibiting complement activity and methods of treating complement-related indications with the C5 inhibitor compounds and compositions are provided.
Highly Active Chiral Dilithium(I) Binaphthyldisulfonate Catalysts for Enantio- And Chemoselective Strecker-Type Reactions
Hatano, Manabu,Nishio, Kosuke,Mochizuki, Takuya,Nishikawa, Keisuke,Ishihara, Kazuaki
, p. 8178 - 8186 (2019/08/22)
An enantioselective Strecker-type reaction of aldimines and ketimines was developed by using a chiral dilithium(I) binaphthyldisulfonate as a chiral acid-base cooperative catalyst. The present catalytic system features an extremely short reaction time (10 min to 4 h), unlike conventional catalytic systems. Along with the design of stronger chiral Li(I) Lewis acid catalysts, a highly reactive pentacoordinate silicate generated in situ could promote the reactions. In particular, instead of unstable N-Bn Strecker products, more stable N-CH2(9-anthryl) and N-CH2(1-naphthyl) Strecker products could be obtained in high yields with high enantioselectivities. By a switch of the present and previous catalyst systems, chemoselective cyanation to a ketoaldimine could be performed, respectively. Moreover, mechanistic investigations provided useful information regarding the active catalysts, catalytic cycles, and possible transition states.
RETRACTED ARTICLE: Chemoenzymatic Method for Enantioselective Synthesis of (R)-2-Phenylglycine and (R)-2-Phenylglycine Amide from Benzaldehyde and KCN Using Difference of Enzyme Affinity to the Enantiomers
Kawahara, Nobuhiro,Asano, Yasuhisa
, p. 5014 - 5020 (2018/10/20)
In general, enzymatic and chemoenzymatic methods for asymmetric synthesis of α-amino acids are performed using highly enantioselective enzymes. The enzymatic reactions using α-aminonitrile as a starting material have been performed using reaction conditions apart from the chemical Strecker synthesis. We developed a new chemoenzymatic method for the asymmetric synthesis of α-amino acids from aldehydes and KCN by performing Strecker synthesis and nitrilase reaction in the same reaction mixture. Nitrilase AY487533 that showed rather low enantioselectivity in hydrolysis of 2-phenylglycinonitrile (2PGN) to 2-phenylglycine (2PG) was utilized in the hydrolysis of aminonitrile formed from benzaldehyde and KCN via 2PGN by Strecker synthesis, preferentially synthesizing (R)-2PG with more than 95 % yield and enantiomeric excess (ee). The method was also utilized for the synthesis of (R)-2-phenylglycine amide ((R)-2PGNH2) from benzaldehyde and KCN by the chemoenzymatic reaction in the presence of a mutated nitrilase AY487533W186A, which catalyzes the conversion of 2PGN to 2PGNH2.
Synthetic method for chiral alpha-aminoamide compounds
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Paragraph 0039; 0040; 0041, (2018/01/11)
The invention provides a synthetic method for chiral alpha-aminoamide compounds, belongs to the technical field of organic synthetic methodology, and concretely relates to a synthetic method for chiral alpha-aminoamide compounds, wherein the method has a simple process, low costs and good economy. The method comprises the following steps: 1, performing ammonolysis: adding substituted chiral alpha-aminocarboxylate hydrochloride into concentrated ammonia water, performing stirring for 4-12h under a room temperature, wherein each 1mmol substituted chiral alpha-aminocarboxylate hydrochloride is corresponding to 2-8mL the concentrated ammonia water; 2, after a reaction is finished, performing distillation for removing ammonia water after the reaction to obtain crude products chiral alpha-aminoamide compounds; and 3, performing filtration on the obtained crude products chiral alpha-aminoamide compounds by adopting a manner of adding a solvent or performing purification on the obtained crude products chiral alpha-aminoamide compounds through a manner of column chromatography which uses ammonia water as a mobile phase to obtain the products chiral alpha-aminoamide compounds. Compared with the prior art, a large number of an ammonia gas for ammonolysis is not needed in the method, the process and post-treatment are simple, costs are low and reaction time is short.
CHIRAL FLUORINATING REAGENTS
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Page/Page column 44, (2014/05/24)
This invention relates to fluorinating agents and, more particularly, to chiral non-racemic fluorinating agents useful for enantioselective fluorination, as well as to their synthesis and use and other subject matter. The fluorinating agents are based on a substituted 1,4-diazabicyclo[2.2.2]octane (DABCO) skeleton and provide electrophillic fluorine enantioselectively.
Enantioselective ammonolysis of phenylglycine methyl ester with lipase-pluronic nanoconjugate in tertiary butanol
Wu, Xiaoling,Wang, Rui,Zhang, Yifei,Ge, Jun,Liu, Zheng
, p. 1407 - 1410 (2014/08/18)
Asymmetrical ammonolysis of (R)- and (S)-phenylglycine methyl ester was carried out by using a lipase (CALB)-polymer (Pluronic) nanoconjugate as the catalyst, displaying a 11-fold increased catalytic rate compared to the free CALB in tertiary butanol. Graphical Abstract: The asymmetrical ammonolysis of (R)- and (S)-phenylglycine methyl ester was accomplished using a lipase-Pluronic nanoconjugate, displaying a 11-fold higher catalytic rate compared to the free lipase.[Figure not available: see fulltext.]
Catalyst development for organocatalytic hydrosilylation of aromatic ketones and ketimines
Malkov, Andrei V.,Stewart-Liddon, Angus J. P.,McGeoch, Grant D.,Ramirez-Lopez, Pedro,Kocovsky, Pavel
scheme or table, p. 4864 - 4877 (2012/07/28)
A new family of Lewis basic 2-pyridyl oxazolines have been developed, which can act as efficient organocatalysts for the enantioselective reduction of prochiral aromatic ketones and ketimines with trichlorosilane, a readily available and inexpensive reagent. 1-Isoquinolyl oxazoline, derived from mandelic acid, was identified as the most efficient catalyst of the series, capable of delivering high enantioselectivities in the reduction of both ketones (up to 94% ee) and ketimines (up to 89% ee).
BENZAMIDES AND NICOTINAMIDES AS SYK MODULATORS
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Page/Page column 89-90, (2012/05/20)
The present invention is directed to compounds of formula I and pharmaceutically acceptable salts, esters, and prodrugs thereof which are inhibitors of Syk kinase. The present invention is also directed to intermediates used in making such compounds, the preparation of such a compound, pharmaceutical compositions containing such a compound, methods of inhibition Syk kinase activity, methods of inhibition the platelet aggregation, and methods to prevent or treat a number of conditions mediated at least in part by Syk kinase activity, such as Non Hodgkin's Lymphoma.
Preparation of cross-linked enzyme aggregates of l-aminoacylase via co-aggregation with polyethyleneimine
Vaidya, Bhalchandra K.,Kuwar, Suyog S.,Golegaonkar, Sandeep B.,Nene, Sanjay N.
experimental part, p. 184 - 191 (2012/03/22)
l-Aminoacylase from Aspergillus melleus was co-aggregated with polyethyleneimine and subsequently cross-linked with glutaraldehyde to obtain aminoacylase-polyethyleneimine cross-linked enzyme aggregates (termed as AP-CLEA). Under the optimum conditions, AP-CLEA expressed 74.9% activity recovery and 81.2% aggregation yield. The said method of co-aggregation and cross-linking significantly improved the catalytic stability of l-aminoacylase with respect to temperature and storage. AP-CLEA were employed for enantioselective synthesis of three unnatural amino acids (namely: phenylglycine, homophenylalanine and 2-naphthylalanine) via chiral resolution of their ester-, amide- and N-acetyl derivatives. The enantioselectivity of AP-CLEA was the highest for hydrolysis of amino acid amides; was moderate for hydrolysis of N-acetyl amino acids and was the least for hydrolysis of amino acid esters. Furthermore, AP-CLEA were found to retain more than 92% of the initial activity after five consecutive batches of (RS)-homophenylalanine hydrolysis suggesting an adequate operational stability of the biocatalyst.
