The yields of the attachment of Boc-Lue-O^-Cs^+, Boc-Gly-O^-Cs^+ or Boc-Phe-O^-Cs^+(1.2 eqv.) to Merrifield resin (1.0eqv.) for 31 hours is 87.3%, 89.1% or 89.6% (the mean values of those detected by weight and by these measured the free amino group, respectively). The yields of the anchoring of Fmoc-Lue-OH, Fmoc-Gly-OH or Fmoc-Phe-OH (3.0 eqv. ) to Wang resin (1.0 eqv.) for 48 hours is 44.2%, 30.4% or 56.2% (the mean values of those detected by weight and those measured by the free amino group, respectively). The results show that the combination ratio of Boc-strategy is at least 33.4% higher than that of the Fmoc-strategy. In addition, difference in the combination ratios between those determined by weight and the those by the free amino group is below 2.7%, but weight method is more convenient and feasible.

Key words: AMINO ACID, SOLIDPHASE SYNTHESIS, RESIN, BINDING, CESIUM COMPOUNDS