Exploring neutral backbones in phosphorodiamidate morpholino oligomers: synthesis and biophysical properties

The synthesis of morpholino dimer chlorophosphoramidates and phosphoramidites has been successfully achieved and the method has been used for short oligomer synthesis. Neutral backbone chemistries like urea, carbamate, methylene and glycine linkages were introduced into a 12-mer PMO, followed by thermal melting and circular dichroism analysis. The findings provide a foundation for the development of next-generation antisense oligonucleotides.