Protected forms of 1,2,3-propanetriol andcis, cis-1,3,5-cyclohexanetriol were incorporated onto solid supports which were exploited in the solid phase synthesis of 3′-3′ linked oligodeoxyribonucleotides (ODNs), involving only nucleoside 3′-phosphoramidites as building blocks, UV thermal denaturation analysis showed the ability of ODNs with this inversion of polarity motif to cooperatively hybridize with duplexes of the type 5′-(Pu)m(Py)n-3′ in an alternate strand recognition approach.