5'-O-Acetyl-2', 3'-O-isopropylidene-5-bromouridine (1) gave the 6-cyanouridine (2) by treatment with sodium cyanide at room temperature. Heating of 2 with sodium cyanide afforded the 5-cyanouridine derivative (3) by the addition-elimination mechanism. This method provides a convenient route of the preparation of 5-cyanouridine and 5-cyano-2'-deoxyuridine. The cyano function of 2 was converted to the amide, thioamide, carboxyl, hydroxymethyl, chloromethyl, methyl, cyanomethyl, and carboxymethyl group, respectively. The circular dichroism (CD) spectra of 6-substituted uridines prepared in this work showed all positive CD bands, though existed mainly as the syn-form as determined by the nuclear magnetic resonance measurements.