Dde-protected PNA monomers, orthogonal to Fmoc, for the synthesis of PNA-peptide conjugates

Peptide nucleic acids have become, arguably, one of the most interesting of DNA mimics. Herein the efficient solution phase synthesis of four novel 1-(4,4-dimethyl-2,6-dioxacyclohexylidene)ethyl/4-methoxytrityl (Dde/Mmt) protected PNA monomers is reported which were then used to synthesise PNA-peptide conjugates through a mild Dde deprotection strategy, which was fully orthogonal to Fmoc chemistry, allowing at will Fmoc peptide and Dde-PNA synthesis. (c) 2005 Elsevier Ltd. All rights reserved.