The pentanucleotide which has the sequence of 8th-12th base of the 5''-terminus of yeast tyrosine tRNA, UpApm2GpCpC was synthesized by stepwise addition of properly protected mononucleotides using dicyclohexylcarbodiimide. 5''-O-Monomethoxytrityl-N2-methylguanosine 3''-phosphate was prepared by phosphorylation of the 5''-protected nucleoside to give the 2'',3''-cyclic phosphate and successive hydrolysis with RNase St. The isolated yields of the protected di-, tri, tetra-, and penta-nucleotides were 75, 38, 31, and 21%, respectively. The 5''-terminal tetranucleotide CpUpCpUp corresponding to 1st-4th nucleotides, was synthesized by condensation of the dinucleotide, Bz-CBz(OBz)-pU(OBz)-p and the anilidate, CBz(OBz)-pU-(OBz)-pNHPh in a yield of 22%. The trinucleotide CpGpGp spanning 5th-7th nucleotides from the 5''-end was also prepared by the amidate method from the dinucleotide, MMTrCBz(OBz)-pGiBu(OiBu)-p and GiBu(OiBu)-pNHPhOCH/3 in a yield of 17%.