1.European Molecular Biology Laboratory, Meyerhofstrasse 1, D-69117, Heidelberg, Germany ;2.Department of Nuclear Medicine, Klinikum der Universit?t Heidelberg, Im Neuenheimer Feld 400, D-69120, Heidelberg, Germany ;
Abstract:
Summary A convenient route for the preparation of peptide nucleic acid (PNA) monomers is described. Two different baselabile protecting
groups (2-cyanoethyl and 4-nitrophenylethyl) are described for the protection of the carboxylic function of theN-(2-aminoethyl)glycine backbone during the assembly of the monomers. These groups are selectively removed yielding the desired
PNA monomers in high yields, the 2-cyanoethyl group being faster and cleaner than the 4-nitrophenylethyl group. The use of
PNA monomers for the preparation of DNA-PNA chimeric molecules is also discussed.