PNA (Peptide Nucleic Acids) 其結構類似DNA，利用N-(2-amino-ethyl) glycine的polyamide結構取代了原本DNA中的ribose-phosphate的骨架結構。在PNA的結構中，由於沒有磷酸根存在，所以不會發生電荷排斥現象，因此PNA預期將比DNA有更好的鍵結親和力。

為了研發具更強生物活性與更佳合成產率的PNA分子，我們設計了一個結構修飾的，新PNA分子。同時經由改良Ugi-4CR的多組成合成反應，設計出了一組方便且實用的，新PNA單體分子的合成策略，並且成功的合成出以尿嘧啶為鹼基的一組PNA單體分子。藉由改變不同的鹼基醛類，我們還可以繼續合成其他三組的鹼基的PNA單體分子。

PNA (Peptide Nucleic Acids) is a DNA analogue, in which the backbone consisting of repeating N-(2- aminoethyl) glycine units replace the ribose
phosphate backbone in the DNA structure.

Since the backbone of PNA contains no charged phosphate groups, the binding between PNA/DNA strands is stronger than between DNA/DNA
strands due to the lack of electrostatic repulsion.

In order to optimize the bioactivity and the yield. We design a modified PNA structure. We improve the Ugi-4CR reaction and design a new PNA monomer synthesis strategy, and successful in synthesis a modified New PNA monomer of Uracil as base. By changing the base-aldehyde, we can
synthesis further others three PNA monomers.

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