Nucleoside und Nucleotide. Teil 3. Über die Polykondensation von Thymidin‐3′‐phosphat nach der Triestermethode

Condensation of a mixture of 25 mole per cent of 5′‐O‐ p ‐methoxy‐trityl‐thymidine3′‐[(β‐cyanoethyl)phosphate] and 75 mole per cent of thymidine 3′‐[(β‐cyanoethyl)phosphate] in pyridine yielded a mixture of oligonucleotides, the largest being the pentanucleotide. It was demonstrated that longer chains are not obtained due to the formation of a C‐pyridinium‐thymidine nucleotide. For avoiding this undesired side reaction, the condensation was carried out using sym. ‐collidine as solvent. The analogous side reaction was not observed, longer chains of oligonucleotide were not obtained, however.