PURPOSE: To prepare the titled compound useful as a drug, without protecting the side chain ketone group, by using a compound such as 9-acetyl-6,9,11-trihydroxy-7,8,9,10-tetrahydronaphthacene-5,12-dione, as a raw material.
CONSTITUTION: The objective compound of formula VII (R' is H or alkanoyl) can be prepared by (1) reacting the compound of formulaIwith a halogenation reagent such as N-bromosuccinimide to obtain the compound of formula II (X is halogen), (2) reacting the product with a carboxylic acid metal salt of formula III (R is lower in a solvent such as diethyl ether in the presence of a halogenation reagent such as chlorine to obtain the compound of formula V, (4) reacting the comound with sodium salt or potassium salt of trifluoroacetic acid and hydrolyzing the resultant compound of formula VI, and (5) if necessary further hydrolyzing the produced compound.
SATOU HIROMI
ISHIZUMI KIKUO
