Incorporation of Biaryl Units into the 5′ and 3′ Ends of Sense and Antisense Strands of siRNA Duplexes Improves Strand Selectivity and Nuclease Resistance

Small interfering RNA (siRNA) is a noncoding RNA with considerable potential as a new therapeutic drug for intractable diseases. siRNAs can be rationally designed and synthesized if the sequences of the disease-causing genes are known. In this paper, we describe the synthesis and properties of siRNAs modified with biaryl units. We found that incorporation of biaryl units into the 5′ and 3′ ends of sense and antisense strands of siRNA duplexes improved strand selectivity and nuclease resistance.