Restriction endonucleases can be used to confirm a structure of unusual DNA duplexes.

Cyclic and polycyclic oligonucleotides were synthesized using chemical ligation. Two types of catenanes with one and several intertwinings were produced. The yield of these molecules depended on the ligation conditions and nucleotide sequence of the ligated oligonucleotide and its template. Structure of ligation products was investigated and confirmed using restriction endonuclease MvaI. Interaction of the synthesized molecules with restriction endonucleases SsoII, EcoRII and HindIII was also studied.