New isoindolinone derivatives isolated from the fruiting bodies of the basidiomycete Hericium coralloides

Abstract

Preparative high-performance liquid chromatography (HPLC) purification of the ethyl acetate extract derived from dried basidiomes of the European mushroom Hericium coralloides led to the identification of two previously undescribed isoindolinone derivatives named corallocins D and E (1-2). The structures of the compounds were elucidated based on HR-ESI-MS (high-resolution electron spray ionization mass spectrometry), interpretation of 1D and 2D NMR spectra, electronic circular dichroism (ECD) experiments, and comparisons with published and theoretical data. The metabolites were tested for their cytotoxic and antimicrobial effects in vitro where weak to moderate biological effects were observed against HeLa cells (KB 3.1), Mucor hiemalis and Bacillus subtilis.

Unveiling the Chemical Composition and Biofunctionality of Hericium spp. Fungi: A Comprehensive Overview

“…The structures of these compounds were elucidated using HR-ESIMS and NMR analyses. Through electronic circular dichroism (ECD) experiments, the absolute configuration of both compounds was determined to be the R configuration, as they share a similar sole chiral center and exhibit close positive values (+24 and +26, respectively) [ 55 ]. Corallocins B–E share the same isoindolinone structure with a different substitution at N-2, while corallocin C is distinguished as a rare indole isoindolinone derivative.…”

“…In another study, corallocin A was isolated from H. erinaceus and exhibited the ability to elicit strong survival and neurotrophic responses on hippocampal neurons’ (DIV3) culture in the absence of serum supplementation [ 56 ]. Additionally, corallocins D and E were assessed for their cytotoxic and antimicrobial effects in vitro, showing weak to moderate cytotoxicity against HeLa cells (KB 3.1), Mucor hiemalis, and Bacillus subtilis [ 55 ].…”