ANTHRACYCLINES. CYCLOADDITIONS OF 9-CHLORO-10-HYDROXY-1,4-ANTHRAQUINONE WITH VARIOUS BUTA-1,3-DIENES
作者:Nand L. Agarwal、Hans W. Scheeren
DOI:10.1246/cl.1982.1057
日期:1982.7.5
4-anthraquinone (10) affords an efficient, regiospecific access in two steps to tetracyclic ketones (12–14) which have been investigated as intermediates for the synthesis of anthracycline derivatives. Butadienes with a less asymmetric II-electron distribution than 9 give lower regiospecificity in cycloadditions with 10. Depending on the substituents in the used butadiene, the obtained cycloadducts are