AN INFRARED STUDY OF HYDROGEN-BONDING SPECIFICITY OF HYPOXANTHINE AND OTHER NUCLEIC ACID DERIVATIVES

Previous infrared studies of chloroform-soluble derivatives of the nucleic acid purines and pyrimidines have demonstrated considerable selectivity in hydrogen-bond formation. Hypoxanthine is an important minor base found in transfer RNA, often in the anti-codon position. This has prompted the extension of these studies to include the hydrogen-bonded association of a chloroform-soluble hypoxanthine derivative (2,3-benzylidine-5′-trityl-inosine (I)) with appropriate derivatives of guanine, cytosine, adenine, thymine and uracil. It was found that (I) associates strongly with the cytosine derivative, rather weakly with the adenine derivative, and scarcely at all with the other bases. Estimates have been made of the pair-wise association constants of the various bases in chloroform solution. © 1969.