Helical Folding of Abiotic Chiral Poly(phosphodiester)s

Functions of biomolecules are intimately linked to their structures which result from the folding of a linear sequence of building blocks, amino-acids for proteins and nucleotides for DNA. In the quest to achieve functions with similar efficiency and selectivity that of biomolecules, several synthetic mimics of secondary structures of proteins have been developed but, on the other hand, only scares examples of de novo design of DNA mimics are available. Most of described DNA inspired molecular systems are based on modifications of either the sugar/phosphate backbone or nucleobases. Here are presented the design, the synthesis and the structural characterization of a new class of synthetic phosphodiester oligomers, composed of an aromatic chiral building block, that fold into single helical architectures. Folding pattern diverge from its natural counterpart (DNA) but through intramolecular H-bonds and aromatic stacking these oligomers show similar cooperative temperature dependence stability.