1067-87-4Relevant articles and documents
Multicomponent synthesis of dihydropyrimidines and thiazines
Vugts, Danielle J.,Koningstein, Manoe M.,Schmitz, Rob F.,De Kanter, Frans J. J.,Groen, Marinus B.,Orru, Romano V. A.
, p. 7178 - 7189 (2007/10/03)
A broad range of differently substituted dihydropyrimidines and thiazines can be efficiently prepared by using a four-component reaction between phosphonates, nitriles, aldehydes, and iso(thio)cyanates. The scope and limitations of this multicomponent reaction are fully described. Variation of all four components has been investigated. The nitrile and aldehyde inputs can be varied extensively, but variation of the phosphonate input remains limited. An interesting rearrangement leading to phosphoramidates has been observed, Furthermore, the multicomponent reaction seems to be restricted to the use of isocyanates with strongly electron-withdrawing substituents, but an interesting additional exchange reaction under microwave conditions leads to dihydropyrimidines with less electron-withdrawing substituents at N3. In addition, a diastereoselective formation of dihydropyrimidines has been observed when using a chiral aldehyde as the input. Finally, by changing the isocyanate component to an isothiocyanate, thiazines are efficiently formed instead of the corresponding thio-dihydropyrimidines.
Phosphonic systems. Part XI. Reaction of diethyl propenylphosphonate carbanion with aromatic aldehydes. Mechanistic study
Muller, E. L.,Modro, T. A.
, p. 668 - 672 (2007/10/02)
Diethyl prop-2-enylphosphonate (allylic phosphonate) when treated with BuLi gives the lithiated derivative which adds to aromatic aldehydes via the α or γ carbon atom of the allylic system.The addition is fully reversible, and the α-adducts represent the kinetic, while the γ-adducts the termodynamic products.Diethyl prop-1-enylphosphonate (vinylic phosphonate) does not react with aldehydes under those conditions; conjugate addition of the organolithium reagent to the α,β-unsaturated olefinic bond occurs instead.Key Words: allylic phosphonates; vinylic phosphonates; reversible addition to aldehydes; lithiation.
Synthesis and Biological Evaluation of Cyclopropyl Analogues of 2-Amino-5-phosphonopentanoic Acid
Dappen, Michael S.,Pellicciari, Roberto,Natalini, Benedetto,Monahan, Joseph B.,Chiorri, Claudio,Cordi, Alex A.
, p. 161 - 168 (2007/10/02)
A series of cyclopropyl analogues related to 2-amino-5-phosphonopentanoic acid (AP5) were synthesized and their biological activity was assessed as competitive antagonists for the N-methyl-D-aspartate (NMDA) receptor.In vitro receptor binding using -L-glutamate as the radioligand provided affinity data, while modulation of MK-801 binding was used as a functional assay.The analogues were also evaluated in kainate binding to assess selectivity over non-NMDA glutamate receptors.Of the compounds tested, 4,5-methano-AP5 analogue 26 was the most potent selective NMDA antagonist; however, potency was lower than that for methyl>phosphonic acid (CGS 19755, 5).