Peptide nucleic acid (PNA) is an artificial nucleic acid with a DNA/RNA-like structure and its backbone changed from sugar–phosphate to N-(2-aminoethyl)glycine units that are bound with peptide bonds. PNAs have improved sequence specificity, affinity and stability to the target DNA/RNA because PNA is considered as DNA with a neutral peptide backbone, which cancels the repulsion from negative charge in the sugar–phosphate backbone. Furthermore, PNA is easy-to-handle due to its resistance to nucleases and proteases. The use of PNAs in the hybridization of DNA and RNA is expected to expand genetic studies.

TCI offers PNA monomers (adenine, guanine, cytosine and thymine) protected with an Fmoc group and a Bhoc group. In addition, TCI can deal with the synthesis of various kinds of derivatives and scale-up synthesis.