13893-45-3Relevant academic research and scientific papers
Accessing d-Valine Synthesis by Improved Variants of Bacterial Cyclohexylamine Oxidase
Gong, Rui,Yao, Peiyuan,Chen, Xi,Feng, Jinhui,Wu, Qiaqing,Lau, Peter C. K.,Zhu, Dunming
, p. 387 - 390 (2018)
Chemoenzymatic deracemization was applied to prepare d-valine from racemic valine ethyl ester or l-valine ethyl ester in high yield (up to 95 %) with excellent optical purity (>99 % ee) by employing a newly evolved cyclohexylamine oxidase (CHAO) variant Y321I/M226T exhibiting catalytic efficiency that was 30 times higher than that of the wildtype CHAO. Interestingly, CHAO and its variants showed opposite enantioselectivity for valine ethyl ester and phenylalanine ethyl ester.
Ketoprofen-based ionic liquids: Synthesis and interactions with bovine serum albumin
?wi?tek, Ewelina,Angelov, Ivan,Guncheva, Maya,Janus, Ewa,Kardaleva, Proletina,Klebeko, Joanna,Ossowicz, Paula,Yancheva, Denitsa
, (2020)
The development of ionic liquids based on active pharmaceutical ingredients (API-ILs) is a possible solution to some of the problems of solid and/or hydrophobic drugs such as low solubility and bioavailability, polymorphism and an alternative route of administration could be suggested as compared to the classical drug. Here, we report for the first time the synthesis and detailed characterization of a series of ILs containing a cation amino acid esters and anion ketoprofen (KETO-ILs). The affinity and the binding mode of the KETO-ILs to bovine serum albumin (BSA) were assessed using fluorescence spectroscopy. All compounds bind in a distance not longer than 6.14 nm to the BSA fluorophores. The estimated binding constants (KA) are in order of 105 L mol-1, which is indicative of strong drug or IL-BSA interactions. With respect to the ketoprofen-BSA system, a stronger affinity of the ILs containing l-LeuOEt, l-ValOBu, and l-ValOEt cation towards BSA is clearly seen. Fourier transformed infrared spectroscopy experiments have shown that all studied compounds induced a rearrangement of the protein molecule upon binding, which is consistent with the suggested static mechanism of BSA fluorescence quenching and formation of complexes between BSA and the drugs. All tested compounds were safe for macrophages.
Stereospecific Synthesis of 3,4-Dihydro-2 H-naphtho-1,4-oxazin-2-ones by Unification of Benzoxepine-4-carboxylates with Chiral Amino Acid Ethyl Esters
Bhimapaka, China Raju,Kasagani, Veera Prasad,Kurma, Siva Hariprasad
, p. 2976 - 2983 (2020)
A novel and efficient stereocontrolled method has been developed for the preparation of chiral 3,4-dihydro-2H-naphtho[1,2-b][1,4]oxazin-2-ones by the reaction of benzoxepine-4-carboxylates with chiral amino acid ethyl esters for the first time. The chiral 3,4-dihydro-2H-naphtho-1,4-oxazinones have been achieved in one step by the formation of C-N, C-C, and C-O bonds.
Design and synthesis of a s-triazene based asymmetric organocatalyst and its application in enantioselective alkylation
Mangawa, Shrawan K.,Singh, Ashawani K.,Awasthi, Satish K.
, p. 61144 - 61147 (2015/08/03)
A very efficient chiral organocatalyst was prepared from the readily available cyanuric chloride. The asymmetric catalyst exhibited a highly enantioselective catalytic performance for the alkylation of a glycinate Schiff base, which provides a useful procedure for the enantioselective synthesis of structurally diverse natural and unnatural α-alkyl-α-amino acids.
A Strategy Towards the Stereoselective Synthesis of 5-Hydroxylysine
Loehr, Birgit,Orlich, Simone,Kunz, Horst
, p. 1139 - 1141 (2007/10/03)
A stereoselective synthesis of 5-hydroxylysine is described in which the α-stereogenic centre is generated by a Schoellkopf amino acid synthesis, and the ethanolamine structure is obtained via Sharpless aminohydroxylation from an olefin moiety. The reactions and their selectivities are studied.
A Concise Synthesis of Optically Active 2- Bromotryptophan Amino Acids Present in Konbamide and Jaspamide Via A Regiospecific Bromination Procedure
Zhang, Puwen,Liu, Ruiyan,Cook, James M.
, p. 9133 - 9136 (2007/10/02)
A highly stereoselective synthesis of optically active 2-bromo-5-hydroxytryptophan 1a and important derivatives 1b and 1c as well as their 2-bromotryptophan analogs was achieved in three steps from 2-bromo-3-bromomethylindoles 3a and 3b, respectively.
A New Chiral Glycine Synthon. Synthesis, X-Ray Structure of (-)-(2S,4R)-2-Ethoxycarbonyl-4-phenyl-1,3-oxazolidine and Diastereoselective Nucleophilic Ring Opening to (R)-Ethyl α-Amino Carboxylates.
Andres, Celia,Gonzalez, Alfonso,Pedrosa, Rafael,Perez-Encabo,Garcia-Granda, Santiago,et al.
, p. 4743 - 4746 (2007/10/02)
Condensation of (R)-N-benzyl-2-phenylglycinol 1 with the methyl hemiacetal of ethyl glyoxylate leads to (2S,4R)-2-ethoxycarbonyl-4-phenyl-1,3-oxazolidine 2 as the major product, obtained as a pure enantiomer after column chromatography.Compound 2 is stereoselectively cleaved by dialkylzinc reagents, prepared from alkylmagnesium iodides and ZnCl2, with moderate to good d.e. (72-94 percent).These compounds, after separation by column chromatography and debenzylation by hydrogenolysis in the presence of 10percent Pd on carbon, lead to enantiomerically pure ethyl α-amino carboxylates with good chemical yields. Key words: Chiral Oxazolidines, alpha-amino Esters, Chiral Glycine Synthon, Ring Opening, Asymmetric Synthesis
