Anti-inflammatory Dimeric Tetrahydroxanthones from an Endophytic Muyocopron laterale

Abstract

Twelve new dimeric tetrahydroxanthones, muyocoxanthones A–L (1–12), were isolated from the endophytic fungus, Muyocopron laterale. Their structures were characterized on the basis of the interpretation of NMR and HRESIMS data. The absolute configurations of 1–10 and 12 were unambiguously determined by ECD spectrum data and single-crystal X-ray diffraction analysis. Compounds 2, 6, and 11 showed inhibitory activity against the LPS-induced production of nitric oxide (NO) in RAW 264.7 cells with IC50 values of 5.2, 1.3, and 5.1 μM, respectively.

The Asymmetric Synthesis of Polycyclic Tetrahydroxanthone via the Cascade Reaction of Alkene‐Substituted 1,3‐diketones and Alkenyloxindoles

“…The development of highly efficient asymmetric methodologies for the construction of complex polycyclic scaffolds has triggered intense interest within both the synthetic and medicinal communities due to their potent biological effects. Among them, polycyclic tetrahydroxanthone stands out as a prominent direction [1–2] . The biological significance and structural features of these compounds have resulted in the development of a variety of strategies for their construction [3] (Figure 1).…”

“…Among them, polycyclic tetrahydroxanthone stands out as a prominent direction. [1][2] The biological significance and structural features of these compounds have resulted in the development of a variety of strategies for their construction [3] (Figure 1). As we know, many elegant routes have been discovered to rapidly assemble this chiral framework from readily available starting materials.…”

Aculeaxanthones A–E, new xanthones from the marine-derived fungus Aspergillus aculeatinus WHUF0198

“…The homodimers are composed of the same two chromanone lactone subunits (a γ-lactone moiety linked to a dihydrobenzopyranone) or two tetrahydroxanthone monomers, while the heterodimers consist of two different tetrahydroxanthone monomers and/or chromanone monomers or their derivatives (Zhang et al, 2008;El-Elimat et al, 2015). Due to their interesting chemical properties and a broad spectrum of bioactivities, for instance, antimicrobial, antiviral, anti-inflammatory, and antiparasitic activities as well as cytotoxicity (Cai et al, 2014;Wu et al, 2015;Luenne et al, 2021;Sadorn et al, 2021;Cao et al, 2022;Phang et al, 2022), dimeric tetrahydroxanthones have been extensively studied in chemical and pharmacological fields (Masters and Brase, 2012;Roensberg et al, 2013;Qin et al, 2015a;Qin and Porco, 2015;Xiao et al, 2017;Lv et al, 2021).…”

Paecilins F–P, new dimeric chromanones isolated from the endophytic fungus Xylaria curta E10, and structural revision of paecilin A

“…They are widely distributed in plants, fungi, and lichens (Duan et al, 2019). Chromanones usually form homodimers or heterodimers with xanthones, the biosynthetic precursors of chromanones, with different linkages, including C6-C6, C6-C8, and C8-C8 (Wu et al, 2015;Cao et al, 2022). To unambiguously determine the absolute or even relative configurations of these dimers remains challenging because of the presence of various chiral centers, sometimes with axial chirality.…”