Synthesis of 4-Thiothymine Based Photolabels as New Tools for Nucleic Acids Structural Studies in Solution: Formation of Long-Range Photo-Cross-Links within a Hammerhead Ribozyme Domain
The nucleosidic photolabels 2–5, able to form long-range photo-cross-links, have been used to further investigate the tertiary folding of a hammerhead ribozyme domain. These photolabels derive from 2′-deoxyuridine which is substituted at its C-5 position with a photoactivable 4-thiothymine unit linked by a chain of various length and rigidity. Derivatives 2–5 were inserted at strategic positions of
The new nucleic acid photoaffinity probes 1a, 1b, 2 and 3 in which a 4-thiothymine is linked at the end of a variable chain introduced at the C-5 position of deoxyuridine have been constructed.