Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Synthesis of the diversifiable pentacycline precursors 47 and 48 by Michael–Claisen cyclization using the phenyl naphthoate ester 46 and enone 1 as substrates, with deprotonation in situ. Further transformation of 48 by a reductive amination reaction provides a route to 7-dimethylamino-alkylaminomethylpentacyclines, as illustrated by the synthesis of the 7-dimethylamino-azetidinylmethylpentacycline 49.
