Journal or Book Title
The Journal of Organic Chemistry
The preparation of a tetradeoxy anthracyclinone is described. The key reaction is the cyclization of the acetylenic coumarin 10 to anthraquinone 11. Interestingly, the related model system 12 failed to cyclize. The transformation of 11 into the desired compound 13 was effected by straightforward reactions. The key intramolecular cyclization reaction is also useful for the preparation of phthalide quinone 7.
American Chemical Society
Kraus, George A. and Pezzanite, John O., "Synthesis of a modified anthracycline 4,6,9,11-tetradeoxydaunomycinone" (1982). Chemistry Publications. 702.