Sequenzspezifische Cooligokondensation von Nucleinsäure-Bausteinen mit Affinitäts-Schutzgruppen, 2. Cooligomere von 5′-O-[p-Anisyldiphenylmethyl]thymidin und Desoxynucleotiden

The cooligocondensations of 5′-O-[p-anisyldiphenylmethyl]thymidine with thymidylic acid, derivatives of deoxycytidylic acid and deoxyguanylic acid were studied. The cooligomers MMTrdT(pdN)_n (N = nucleoside) were first removed from homooligomers and unreacted nucleotide by passing the reaction mixture through a column of trityl cellulose, then the separation depending on the chain length was achieved on DEAE-cellulose. In the example studied best—the cooligocondensation with N-isobutyryldeoxyguanosine-5′ phosphate—the nucleoside component was completely inserted into the cooligomers; the sequences of chain length 2, 3, 4, and 5 were obtained in 77, 18, 3 and 2% yield. The mean chain length of the product can be altered e.g. by variation of blocking groups and the ratio of starting compounds.