74853-62-6Relevant articles and documents
Synthesis of Polymers of Isocyanides Derived from Tripeptides Containing Imidazolyl, Carboxyl, and Hydroxymethyl Groups
Visser, H. G. J.,Nolte, R. J. M.,Zwikker, J. W.,Drenth, W.
, p. 3133 - 3137 (2007/10/02)
Three optically active polymers of isocyanides, n, which contain imidazolyl, carboxyl, and hydroxymethyl functions in their side chains R, are described.The polymers are derived from the following diastereomeric tripeptides: L-Ala-L-His-L-Ser, L-Ala-L-His-D-Ser, and D-Ala-L-His-L-Ser.The terminal amino groups of these tripeptides are converted into isocyano functions, which are subsequently polymerized with catalytic amounts of nickel(II) chloride.The molecular weights of the polymers are in the Mv range 20000-35000.The CD spectra reveal that the polymers derived from L-Ala-L-His-L-Ser and L-Ala-L-His-D-Ser have right-handed helical configuractions.The pKa values of the imidazolyl and carboxyl groups in the polymers have increased as compared to model compounds.This suggests that strong electrostatic interactions exist between these groups.
Efficient "One-Pot" Synthesis of N-Trityl Amino Acids
Barlos, Kleomenis,Papaioannou, Dionysios,Theodoropoulos, Dimitrios
, p. 1324 - 1326 (2007/10/02)
A sequential procedure has been developed whereby neutral amino acids 1 were tritylated via their corresponding trimethylsilyl esters 2 to afford, after mild hydrolysis, N-trityl amino acids 3 in high yields and purity.Hydroxy amino acids 4 were preferent
