# Panunoids A – D, four new prenylhydroquinone derivatives isolated from the fungus Panus rudis

## TL;DR

Researchers discovered four new compounds from the fungus Panus rudis and tested their effects on cancer cells.

## Contribution

The study reports four new prenylhydroquinone derivatives and their structural elucidation.

## Key findings

- Compounds 1, 3–6, 8, 9, and 12 showed weak cytotoxicity against A-549 and HepG2 cancer cells.
- Compounds 8 and 12 exhibited dose-dependent inhibitory effects with measurable IC50 values.
- Structures were confirmed using NMR, HRESIMS, X-ray diffraction, and ECD spectra.

## Abstract

A chemical constituent study on the fermented rice substrate of basidiomycetous fungus Panus rudis led to the isolation of four previously undescribed prenylhydroquinone derivatives compounds (1–4) and eight known compounds (5–12). Among them, compound 3 featured a rare benzothiazole derivative with hydroxy substituted 3-methyl-1-butenyl substitution on the benzene ring, and the absolute configurations of 7 and 12 were elucidated as unreported ones. Their structures were identified by the interpretation of 1D and 2D NMR spectroscopy, HRESIMS data, X-ray single-crystal diffraction, and comparison of calculated and experimental ECD spectra. The plausible biosynthetic pathways for 1–7 are proposed. Cytotoxicity evaluation was conducted on 1 and 3–12 against two cancer cell lines (A-549 and HepG2). The results demonstrated that 1, 3–6, 8, 9, and 12 exhibited weak cytotoxicity against both two cell lines. Among them, 8 and 12 showed dose-dependent inhibitory effects, and their IC50 values at 72 h were obtained.

The online version contains supplementary material available at 10.1007/s13659-025-00562-3.