A highly efficient enantio- and diastereoselective synthesis of chiral cis-β-N-alkyl/arylamino cyclic alcohols has been realized by asymmetric hydrogenation of racemic α-amino cyclic ketones via DKR catalyzed by [RuCl2((S)-Xyl-SDP)((R,R)-DPEN)]. The enantioselectivities of the reaction were up to 99.9% ee with 99:1 cis-selectivities. A practical catalytic asymmetric synthesis of all four isomers of
Iodine(V) Reagents in Organic Synthesis. Part 3. New Routes to Heterocyclic Compounds via <i>o</i>-Iodoxybenzoic Acid-Mediated Cyclizations: Generality, Scope, and Mechanism
作者:K. C. Nicolaou、P. S. Baran、Y.-L. Zhong、S. Barluenga、K. W. Hunt、R. Kranich、J. A. Vega
DOI:10.1021/ja012126h
日期:2002.3.1
The discovery and development of the o-iodoxybenzoic acid (IBX) reaction with certain unsaturated N-aryl amides (anilides) to form heterocycles are described. The application of the method to the synthesis of delta-lactams, cyclic urethanes, hydroxy amines, and amino sugars among other important building blocks and intermediates is detailed. In addition to the generality and scope of this cyclization
The unusual behavior of hypervalent iodine reagents, Dess - Martin periodinane and IBX, with an array of anilides leads to the formation of complex heterocycles in only one synthetic operation (see scheme). Furthermore, the substrates for these transformations are available in one step from readily available commercial building blocks. The mechanism by which these periodinanes interact with anilides
Molecular Modeling and Anticholinesterasic Activity of Novel 2-Arylaminocyclohexyl<i>N,N</i>-Dimethylcarbamates
作者:Mariane C. Bagatin、Augusto A. Cândido、Glaucia M. S. Pinheiro、Nelci F. Höehr、Miguel Machinski Júnior、Simone A. G. Mossini、Ernani A. Basso、Gisele F. Gauze
DOI:10.5935/0103-5053.20130225
日期:——
This work reports a detailed theoretical and experimental study of the novel isomer series cis- and trans-2-arylaminocyclohexyl N,N-dimethylcarbamates as potential inhibitors of cholinesterases. In vitro inhibition assay by Ellman's method with human blood samples showed that the new carbamates are selective to the inhibition of enzyme butyrylcholinesterase (BuChE) with maximum inhibition of 90% and IC50 of 6 and 8 mmol L-1 for the more actives compounds of the series. Molecular modeling studies point to significant differences for the conformations of the compounds in the active sites of enzymes BuChE and acetylcholinesterase (AChE). The results show that the compounds interact more effectively with the active site of enzyme BuChE since the carbamate group is close to the key residues of the catalytic triad.
ORDERED MESOPOROUS TITANOSILICATE AND THE PROCESS FOR THE PREPARATION THEREOF