Chemoselective Deprotection of Sulfonamides Under Acidic Conditions: Scope, Sulfonyl Group Migration, and Synthetic Applications
作者:Tomas Javorskis、Edvinas Orentas
DOI:10.1021/acs.joc.7b02507
日期:2017.12.15
Chemoselective acidic hydrolysis of sulfonamides with trifluoromethanesulfonic acid has been evaluated as a deprotection method and further extended to more complex synthetic applications. In contrast to conventional troublesome sulfonamide hydrolysis, a near-stoichiometric amount of acid was found to be sufficient to bring about efficient deprotection of various neutral or electron-deficient N-arylsulfonamides
Heterocyclic compounds as P2X7 ion channel blockers
申请人:Shum Patrick
公开号:US20050026916A1
公开(公告)日:2005-02-03
The present invention relates to a novel series of 4,5-diphenyl-2-amino-4,5-dihydro-imidazole derivatives of the formula II:
wherein R, R
1
, R
2
, R
3
, R
4
, R
5
, X and Y are as defined herein. This invention also relates to methods of making these compounds. The compounds of this invention are P2X7 ion channel blockers and are therefore useful as pharmaceutical agents, especially in the treatment and/or prevention of a variety of diseases having an inflammatory component, including inflammatory bowel disease, rheumatoid arthritis and disease conditions associated with the central nervous system, such as stroke, Alzheimer's disease, etc.
Electrophilically activated nitroalkanes in reaction with aliphatic diamines en route to imidazolines
作者:Alexander V. Aksenov、Nicolai A. Aksenov、Nikolai A. Arutiunov、Vladimir V. Malyuga、Sergey N. Ovcharov、Michael Rubin
DOI:10.1039/c9ra08630g
日期:——
A novel synthetic methodology for the assembly of imidazolines via an unusual reaction between nitroalkanes and aliphatic 1,2-diamines in the presence of phosphorous acid is described. In contrast to the related highly efficient preparation of benzimidazoles from aromatic amines, this process represents a major synthetic challenge and for a long time was elusive. Analysis of the method limitations
Nucleophilic addition to substituted 1<i>H</i>-4,5-dihydroimidazolium salts
作者:Alejandra Salerno、Vanina Ceriani、Isabel A. Perillo
DOI:10.1002/jhet.5570340302
日期:1997.5
representing the transfer of the C-2 unit to a nucleophilic carbon. With alkaline cyanides salts 1 react efficiently affording α,α-diaminonitriles 5. In these compounds the cyano group may be readily substituted by nucleophiles (hydroxyl anion, species with nucleophilic carbon and reagents that act by hydride ion transfer), in a way similar to the salts but with better yields.
1 H -4,5-二氢咪唑鎓盐1容易与产生环状产物的亲核试剂反应,该环状产物可以是稳定的或转化为维持结构乙二胺单元的无环化合物。用甲基碘化镁化合物1e可得到预期的咪唑烷,但在取代的1-芳基-3-甲基-2-苯基盐1b-d的情况下,分离出N-芳基-N'-甲基乙二胺3b-d和苯乙酮(4) ,代表C-2单元向亲核碳转移的过程。与碱性氰化物盐1有效反应,得到α,α-二氨基腈5。在这些化合物中,氰基可以很容易地被亲核试剂(羟基阴离子,具有亲核碳的物质以及通过氢化物离子转移作用的试剂)取代,类似于盐,但收率更高。
A Domino Route toward Polysubstituted Pyrroles from 2-Imidazolines and Electron-Deficient Alkynes
作者:Nikita E. Golantsov、Alexandra S. Golubenkova、Alexey A. Festa、Alexey V. Varlamov、Leonid G. Voskressensky
DOI:10.1021/acs.orglett.0c01530
日期:2020.6.19
fragment. Heating the resulting imidazolidines in xylene on air leads to an effective formation of polysubstituted pyrroles through a domino sequence of aza-Claisen rearrangement/transannular nucleophilic addition/oxidative ring opening reactions. The direct one-pot transformation of 2-imidazolines to pyrroles has been also realized.