A Convenient Synthesis of Dicarboxylic Monoesters using Isopropenyl Esters: Synthesis of Oxaunomycin Derivatives
Reaction of various types of alcohols with a novel type of acylating agent, the isopropenyl esters 2a-e in the presence of a catalytic amount of conc. sulfuric acid or toluene-p-sulfonic acid followed by selective deprotection of the terminal ester gives the monoesters 5a-i in good yields.
Convenient Synthesis of Alcohol O-Hemiesters using Isopropenyl Esters as Acylating Reagents: Synthesis of Hydrophilic Oxaunomycin 10-O-Hemiester Derivatives
Various types of alcohol O-hemiesters 7a-m were synthesized conveniently in good yield by reaction with isopropenyl esters 4a-f in the presence of a catalytic amount of conc.H2SO4 or toluene-p-sulfonic acid followed by selective deprotection of the terminal esters.This method was applied to a preparation of hydrophilic oxaunomycin 10-O-hemiester derivatives 14a,b and 19a-c.