A facile and automated procedure for the synthesis of oligodeoxynucleotides possessing derivatives of 9-fluoreneone, 9, 10-anthraquinone, and phenothiazine is described. The phosphoramidite approach is used to attach these redox and spectroscopic probes to the 5'- terminus of oligodeoxynucleotides in high yield (> 95%). Thermal denaturation studies of labeled oligodeoxynucleotides show a slight enhancement in duplex stability relative to ...