A new condensing reagent, 1-(2,4,6-triisopropylbenzenesulfonyl)-5-(pyridin-2-yl)tetrazolide and its use in the synthesis of lambda cro binding heptadecanucleotide on a polymer support.

A new condensing reagent 1-(2,4,6,-triisopropylbenzenesulfonyl)-5-(pyridin-2-yl)tetrazolide (TPSPy) was found to give one diastereoisomer of dinucleoside monophosphate aryl esters. Several oligodeoxynucleotide blocks were prepared using this reagent. A heptadecanucleotide, dTATCCCTTGCGGTGATA, which had the same sequence as the lambda cro binding DNA sequence was synthesized by condensing mono-, tri- and dodecanucleotide blocks using this reagent on a polystyrene support.