596828-16-9Relevant academic research and scientific papers
Multicomponent Hantzsch cyclocondensation as a route to highly functionalized 2- and 4-dihydropyridylalanines, 2- and 4-pyridylalanines, and their N-oxides: Preparation via a polymer-assisted solution-phase approach
Dondoni, Alessandro,Massi, Alessandro,Minghini, Erik,Bertolasi, Valerio
, p. 2311 - 2326 (2007/10/03)
An improved and efficient entry to highly functionalized β-(2-pyridyl)- and β-(4-pyridyl)alanines and the corresponding 1,4-dihydro and N-oxide derivatives has been developed by one-pot thermal Hantzsch-type cyclocondensation of aldehyde-ketoester-enamine
Model studies toward the synthesis of dihydropyrimidinyl and pyridyl α-amino acids via three-component Biginelli and Hantzsch cyclocondensations
Dondoni, Alessandro,Massi, Alessandro,Minghini, Erik,Sabbatini, Simona,Bertolasi, Valerio
, p. 6172 - 6183 (2007/10/03)
A novel and versatile strategy for the synthesis of heterocyclic α-amino acids has been described. The use of components (aldehyde or β-ketoester) bearing a masked glycinyl moiety in Biginelli and Hantzsch cyclocondensations allowed access to the 4-dihydropyrimidinyl-α-glycines, 4-dihydropyrimidinyl-α-alanines, 4-pyridyl-α-alanines, and 2-pyridyl-α-alanines classes. Dihydropyrimidinylamino acids were obtained as a mixture of diastereoisomers due to the formation of the stereocenter at C4 of the dihydropyrimidinone ring. Individual stereoisomers were isolated as pure compounds and their structures were assigned with the aid of X-ray crystallography and chiroptical properties. The enantiomeric purity of a representative selection of the above amino acids was greater than 96% as verified by derivatization to the corresponding Mosher's amides and subsequent 1H and 19F NMR spectroscopy. Incorporation of the 4-pyridyl-α-alanine derivative into a peptide chain is also described.
