Schiff Bases of Amino Acid Esters as New Substrates for the Enantioselective Enzymatic Hydrolysis and Accompanied Asymmetric Transformations in Aqueous Organic Solvents1,2
摘要:
The enzyme (lipases and chymotrypsin)-catalyzed hydrolysis of Schiff bases derived from racemic amino acid esters and aromatic aldehydes has been investigated. The reactions were successfully carried out in different aqueous organic solvents at ambient temperature, but the aqueous acetonitrile (5.4% water content by volume) was the solvent of choice. The L-amino acid (ee 98%) precipitated out from the solution as the reaction progressed, and the liberated aldehyde and unhydrolyzed D-ester (ee 40-98%) remained in the solution. The range of substrates included amino acids having different types of side chains. The addition of an organic base (DABCO) into the solution resulted in the racemization of the remaining D-ester and the additional hydrolysis of the substrate, thus leading to the effective asymmetric transformation of the initial ester. Upto 87.5% of the initial racemate was converted into the L-enantiomer.
[EN] NOVEL METHOD FOR THE SYNTHESIS OF PERINDOPRIL AND THE PHARMACEUTICALLY ACCEPTABLE SALTS THEREOF [FR] NOUVEAU PROCEDE DE SYNTHESE DU PERINDOPRIL ET DE SES SELS PHARMACEUTIQUEMENT ACCEPTABLES
[EN] NEPRILYSIN INHIBITORS<br/>[FR] INHIBITEURS DE LA NÉPRILYSINE
申请人:THERAVANCE BIOPHARMA R & D IP LLC
公开号:WO2015116786A1
公开(公告)日:2015-08-06
In one aspect, the invention relates to compounds having the formula (I): where R1-R6 are as defined in the specification, or a pharmaceutically acceptable salt thereof. These compounds have neprilysin inhibition activity. In another aspect, the invention relates to pharmaceutical compositions comprising these compounds; methods of using these compounds; and processes and intermediates for preparing these compounds.
A synthetically useful approach for the synthesis of functionalized α, α‐disubstituted α‐amino acid derivatives via palladium‐catalyzed 1,7 addition of readily available aldimine esters to vinylcyclopropanes is reported. This methodology was operated under mild conditions, affording α‐allylic α‐amino esters in good to excellent yields and excellent regio‐ and stereoselectivity. This transformation
Discovery of Potent Antiallodynic Agents for Neuropathic Pain Targeting P2X3 Receptors
作者:Young-Hwan Jung、Yeo Ok Kim、Hai Lin、Joong-Heui Cho、Jin-Hee Park、So-Deok Lee、Jinsu Bae、Koon Mook Kang、Yoon-Gyoon Kim、Ae Nim Pae、Hyojin Ko、Chul-Seung Park、Myung Ha Yoon、Yong-Chul Kim
DOI:10.1021/acschemneuro.6b00401
日期:2017.7.19
vivo, was investigated as a prodrug concept. Intravenous injection of compound 28 resulted in potent antiallodynic effects, with ED50 values of 2.62 and 2.93 mg/kg in spinal nerve ligation and chemotherapy-induced peripheral neuropathy rats, respectively, indicating that new drug development targeting the P2X3 receptor could be promising for neuropathicpain, a disease with high unmet medical needs.
Kinetics of the acetic acid-catalysed ring-opening reaction of 2-phenyl-4,4-dimethyl-2-oxazolin-5-one with some aminoacid ethyl esters in carbon tetrachloride
作者:C. Chuaqui、S. Atala、A. Márquez、H. Rodríguez
DOI:10.1016/0040-4020(73)80101-2
日期:1973.1
ethyl ester of dl-alanine. To explain the function of the catalyst a cyclic intermediate has been compared with other intermediates proposed for similar reactions. A good correlation has been obtained between the rate constant for the catalysed reaction and Taft's σ* values, showing that the effects of the substituents on the esters are mainly polar and supporting the structure of the proposed intermediate