| 摘要 |
<p>4-Substituted anthracyclinones of general formula (I), wherein R represents a hydrogen atom or a COOR1 group in which R1 may be a hydrogen atom or an optionally substituted C1-C10 alkyl group, which are intermediates in the preparation of antitumor anthracycline glycosides, are prepared by: (i) (a) reacting a 4-demethyl-4-sulfonyl-7-deoxy-13-dioxolanyl daunomycinone of formula (V), wherein R' represents an alkyl group having from 1 to 10 carbon atoms optionally substituted by one or more halogen atoms or an aryl group optionally substituted by halogen, alkyl, alkoxy or nitro, in a reducing environment with a catalytic amount of a compound of formula (VIII): MLnL'm, wherein M represents a transition metal atom, L and L', which may be the same or different, each represents an anion or a neutral molecule and n and m may vary from 0 to 4, such as to obtain a compound of formula (VII), wherein R represents hydrogen; or (b) carbonylating a 4-demethyl-4-sulfonyl-7-deoxy-13-dioxolanyl daunomycinone of formula (V) as defined above, with carbon monoxide in the presence of a nucleophile R1OH, wherein R1 is as defined above, an organic or inorganic base and as catalyst a compound of formula (VIII) as defined above, such as to obtain a compound of formula (VII) as shown above wherein R represents a COOR1 group; and (ii) introducing an α-hydroxy group at the 7-position and removing the 13-oxo protecting group by acid hydrolysis from the resultant compound of formula (VII).</p> |
