反应详情

In step d1, the compound (XIX) is reacted with a reactive derivative of carbonic acid, such as phosgene, in solution in toluene, or 1,1-carbonyldiimidazole, in the presence of a base such as triethylamine, N,N-diisopropylethylamine or N-methylmorpholine, in a chlorinated solvent such as dichloromethane or 1,2-dichloroethane, or an ether such as tetrahydrofuran, and at a temperature between -70° C. and room temperature, to give a compound of the expected formula (II) in which E is an O-protecting group.