Novel stabilized activated derivatives of carbamic acid, their process of preparation and their use for the preparation of ureas
申请人:——
公开号:US20020143191A1
公开(公告)日:2002-10-03
Process for the preparation of stable activated derivatives of carbamic acid, comprising at least one protected amino group and an activated carbamic acid function, from an amino acid derivative in which the amino group is protected. The process includes: a) a step of transformation of the —COOH group of the amino acid derivative into a —CON
3
group to obtain an acyl azide; b) a step of transformation of the —CON
3
group of the acyl azide into a —NCO group to obtain an isocyanate; c) a step of treating the isocyanate to obtain a stable derivative of carbamic acid.