Bis-alkenoic acid and amide derivatives from the coprophilous fungus Scopulariopsis cordis

Abstract

The chemical investigation of a strain of Scopulariospsis cordis , isolated from mouse dung, has been conducted, and two bis-alkenoic acid ethers, scopuladienoic acids A and B ( 1 , 2 ), and an amide, ( Z )-docos-16-enamide ( 3 ), along with two known diketopiperazines ( 4 , 5 ), were isolated from its liquid culture. The structures of these compounds were established by extensive spectroscopic and mass spectrometric analyses (1D and 2D NMR, HRMS) and by comparing their data with those already published in the literature. The relative configurations of 1 and 2 were assigned based on the combination of the highly reducing polyketide synthases (HR-PKSs) rules, NOESY correlations, and chemical shift analysis of atoms around the stereogenic centers. The tested compounds ( 1 , 3 −5 ) showed no significant activity against a panel of bacterial and fungal strains (MICs > 66.6 µg/mL) or against the tested cell lines (IC 50 > 37 µg/mL). Despite the lack of activity under these conditions, the identification of structurally novel metabolites highlights the chemical richness of coprophilous fungi and reinforces their value as reservoirs of unexplored natural products with potential relevance to drug discovery. • The chemical investigation of the coprophilous fungus Scopulariopsis cordis was conducted. • Two new bis-alkenoic acid ethers and a new amide were isolated. • The structures of the new metabolites were elucidated using NMR and HRMS analyses. • The isolated compounds were evaluated for their antimicrobial and cytotoxic activities.