Unmasking of aminoanthroquinone moiety through a ring opening in the presence of copper salts and a subsequent cross-coupling/recyclization cascade

In the presence of copper(I) salts, 3-bromo- or 3-iodoisoxazoles undergo isoxazole ring opening to give keto amines that can undergo further one-pot cascade cross-coupling/recyclization transformation into an extended flat polyaromatic ring system that can provide an interesting new platform for the design of DNA intercalators. If necessary, the three-step reaction cascade can be interrupted at a desired intermediate step through a judicious choice of reaction temperature and catalyst.