反应详情

Relative stability of amino-protecting groups, namely Xys, 2-chlorobenzyloxycarbonyl and Z against trifluoroacetic acid. Boc-Lys(Xys)-OH(41.4 mg, 0.1 m.mol), Boc-Lys(2-Cl-Z)-OH.t-butylamine salt (48.8 mg, 0.1 m.mol) and Boc-Lys(Z)-OH.dicyclohexylamine salt (56.1 mg, 0.1 m.mol) are each dissolved in trifluoroacetic acid (0.5 ml) containing anisole (0.03 ml) and the solutions are allowed to stand at room temperature for 24 hours. The trifluoroacetic acid is distilled off and the residue is made up to 20 ml with cold water. An aliquot of this solution is taken and its lysine content is determined by means of an amino acid analyzer. The yields of lysine (% cleavage of ε-amino-protecting groups) are calculated.

1. distillationThe trifluoroacetic acid is distilled off