Synthesis of Pyrrolidinyl PNA and Its Site-Specific Labeling at Internal Positions by Click Chemistry.

Pyrrolidinyl PNA with an α-/β-dipeptide backbone consisting of alternating nucleobase-modified D-proline and (1S,2S)-2-aminocyclopentanecarboxylic acid (also known as acpcPNA) is a class of conformationally constrained PNA that shows exceptional DNA hybridization properties (Watson-Crick base pairing) including very high specificity and the inability to form self-pairing hybrids. This chapter provides details of the syntheses of acpcPNA sequences and its monomer building blocks, as well as protocols for site-specific labeling with one or more fluorescent dyes.