- Easy kinetic resolution of some β-amino alcohols by Candida antarctica lipase B catalyzed hydrolysis in organic media
-
Herein, we present an easy and eco-friendly pathway to obtain some enantiomerically enriched β-amino alcohols using essentially as β-blockers. The enzymatic hydrolysis is conducted in hydrophobic organic media, assisted by sodium carbonate and CAL-B. We describe a new and effective procedure in terms of the chemo- and enantioselectivity, which allows for the formation of both enantiomers: the 2-acetamido-1-arylacetates and 2-acetamido-1-arylethanols were obtained with high ee values (up to >99%), while the selectivities reached E >200. The obtained results show a high CAL-B affinity toward the deacylation of the 2-acetamido-1-arylacetates compared to the acylation one. The structure of the 2-acetamido-1-arylacetates had a significant influence on both reactivity and selectivity of the CAL-B catalyzed deacylation. A multigram scale O-deacylation of racemic 2-acetamido-1-phenylacetate has been carried out, giving access both enantiomers with high enantiomeric purity and good isolated chemical yields.
- Alalla, Affef,Merabet-Khelassi, Mounia,Riant, Olivier,Aribi-Zouioueche, Louisa
-
supporting information
p. 1253 - 1259
(2016/11/23)
-
- Mn-Catalyzed Highly Efficient Aerobic Oxidative Hydroxyazidation of Olefins: A Direct Approach to β-Azido Alcohols
-
(Chemical Equation Presented). An efficient Mn-catalyzed aerobic oxidative hydroxyazidation of olefins for synthesis of β-azido alcohols has been developed. The aerobic oxidative generation of azido radical employing air as the terminal oxidant is disclosed as the key process for this transformation. The reaction is appreciated by its broad substrate scope, inexpensive Mn-catalyst, high efficiency, easy operation under air, and mild conditions at room temperature. This chemistry provides a novel approach to high value-added β-azido alcohols, which are useful precursors of aziridines, β-amino alcohols, and other important N- and O-containing heterocyclic compounds. This chemistry also provides an unexpected approach to azido substituted cyclic peroxy alcohol esters. A DFT calculation indicates that Mn catalyst plays key dual roles as an efficient catalyst for the generation of azido radical and a stabilizer for peroxyl radical intermediate. Further calculation reasonably explains the proposed mechanism for the control of C-C bond cleavage or for the formation of β-azido alcohols.
- Sun, Xiang,Li, Xinyao,Song, Song,Zhu, Yuchao,Liang, Yu-Feng,Jiao, Ning
-
p. 6059 - 6066
(2015/05/27)
-
- ARYL-HYDROXYETHYLAMINO-PYRIMIDINES AND TRIAZINES AS MODULATORS OF FATTY ACID AMIDE HYDROLASE
-
Certain aryl-hydroxyethylamino-pyrimidine and triazine compounds are described, which are useful as FAAH inhibitors. Such compounds may be used in pharmaceutical compositions and methods for the treatment of disease states, disorders, and conditions mediated by fatty acid amide hydrolase (FAAH) activity, such as anxiety, pain, inflammation, sleep disorders, eating disorders, energy metabolism disorders, and movement disorders (e.g., multiple sclerosis). Methods of synthesizing such compounds are also disclosed.
- -
-
Page/Page column 124
(2009/10/18)
-
- 2,5-DIOXOIMIDAZOLIDIN-4-YL ACETAMIDES AND ANALOGUES AS INHIBITORS OF METALLOPROTEINASE MMP12.
-
The invention provides compounds of formula (I) in which L, X, Y, Z1, Z2, R1, R2, R3 and G2 have the meanings defined in the specification; processes for their preparation; pharmaceutical c
- -
-
-
- New biphenyl derivatives II: 1-(4-biphenylyl)-1-hydroxy-2-aminoethanes and 1-(4-biphenylyl)-1-chloro-2-aminoethanes as potential β-adrenoceptor blocking agents
-
Series of 1-(4-biphenylyl)-1-hydroxy-2-aminoethanes and 1-(4-biphenylyl)-1-chloro-2-aminoethanes were synthesized. Newly developed reaction conditions for aryl aminomethyl ketone reduction and reductive alkylation, using sodium borhydride, are described. The prepared compounds were examined for adrenergic blocking activity on an anesthetized dog blood pressure preparation and on isolated toad hearts. β-adrenergic blockade was investigated using isoproterenol as the agonist. The benzylamino and cyclohexylamino analogs exhibited marked β-adrenoceptor blocking activity, for which the latter derivatives were more potent.
- Shafik,Askar
-
p. 776 - 780
(2007/10/05)
-