An efficient synthesis of 9-anthrone lactone derivatives via the Knoevenagel condensation and intramolecular cyclization

One-step synthesis of 9-anthrone lactone derivatives from 1-acetyloxyanthraquinone with a variety of dicarbonyl substrates in the presence of K2CO3 by Knovenagel condensation and intramolecular cyclization is developed. Possible reaction mechanisms have been investigated using the density functional theory (DFT), which has been widely used in the study of reaction mechanism. The strategy could be useful for the synthesis of the core structure of marine natural product aspergiolide.