Synthesis and duplex stability of oligodeoxynucleotides containing 6-mercaptopurine

Article abstract of DOI:10.1016/0040-4039(92)89045-E

simple procedures for conversion of 2′-deoxyinosine into 6-thio-2′-deoxyinosine (III) and for preparation of S-protected 6-mercatopurine phosphoramidite (VI) are described. The monomer (VI) was incorporated into DNA oligomers and converted into oligomers containing 6-mercaptopurine and other purines modified at the 6-position. Measurements of the melting temperature (Tm) of DNA duplexes containing 6-mercaptopurine or 6-thioguanine show that both preferentially pair with cystosine rather than with thymine, but that the presence of the S generally destabilises the DNA duplex.