Asymmetric Conjugate Addition of ortho-Quinone Methides as a Pathway to the Core of Nomofungin

Asymmetric Conjugate Addition of ortho-Quinone Methides as a Pathway to the Core of Nomofungin Introduction: Tetracyclic structures are found at the core of many biologically active molecules. One class of compounds with a tetracyclic core is the family of communesin products. 1 These products have shown cytotoxicity against several leukemia cell lines as well as insecticidal activity against silkworms. Communesins A and B were the first members of the family to be discovered and were extracted from Penicillium sp. found on Enteromorpha intestinalis by Numata et al. Later, a product similar to communesin B except for the presence of a N,O-acetal moiety as opposed to the normal N,N-acetal moiety was isolated and named nomofungin (Figure 1). This product was subsequently shown to actually be communesin B with the N,N configuration. However, the fact that this mistake was made testifies to the similarity of the two structures.