Solid-Phase Synthesis of Cyclic PNA and PNA−DNA Chimeras

A new and versatile on-line automated solid-phase approach to obtain cyclic PNA (I and III) and cyclic PNA−DNA chimeras (II) in highly pure form has been developed. Starting from a Tentagel matrix functionalized with a 3-chloro-4-hydroxyphenylacetic linker, the synthesis of representative, new cyclic molecules by standard peptide and phosphoramidite-based chemistry has been achieved.