Chromanone Lactones: A Neglected Group of Natural Products – Isolation, Structure Elucidation, Bioactivity, and Synthesis

Abstract

Chromanone lactones are a diverse family of fungal metabolites, which is biologically linked to tetrahydroxanthones. These compounds exhibit different structures that could be monomeric or dimeric, with different linkages and in combination with other monomers, but also fused to give more complex structures. They have been neglected so far, as they have not been recognized as an original group of natural products and as most of the publications related to these compounds have arisen only since the beginning of the century. In this Review, we discuss the isolation, the structural elucidation, the bioactivity and also the synthesis of chromanone lactones. Moreover, we present a classification of the different compounds of this family.

Asymmetric Syn-Selective Vinylogous Addition of Butenolides to Chromones via Al-Li-BINOL Catalysis

“…Chromanones are familiar substructures found in many organic natural products. Many compounds in this class, bearing a five-membered lactone at the 2-position (Figure ), exhibit a variety of biological activities . One straightforward tactic to furnish these structures in a stereocontrolled manner involves the catalytic asymmetric addition of butenolides (Figure ).…”

A CommonC2‐Symmetric 2,2’‐Biphenol Building Block and its Application in the Synthesis of (+)‐di‐epi‐Gonytolide A

“…[3] The binaphtho-α-pyranone [4] viriditoxin for instance shows antibacterial activity against drugresistant bacterial pathogens [5] as well as potent antitumor activities, which were also found for a variety of binaphtho-γpyranones [6] such as ustilaginoidin A (Figure 1A). [7] Further examples include the antifeedant bicoumarin isokotanin A [8] or the more complex tetrahydroxanthone dimer [9] rugulotrosin A [10] and chromanone lactone dimer [11] gonytolide A [3b] that feature antibacterial and immuno-stimulating activities, respectively. In many of these dimeric polyketides, rotation around the biaryl axis is hindered, which causes the corresponding molecules to be axially chiral.…”