Angstrom-17

Plant pathogens have led to large yield and quality losses in crops worldwide. The discovery and study of novel agrochemical alternatives based on the chemical modification of bioactive natural products is a highly efficient approach. Here, two series of novel cinnamic acid derivatives incorporating diverse building blocks with alternative linking patterns were designed and synthesized to identify their antiviral capacity and antibacterial activity.

The bioassay results demonstrated that most cinnamic acid derivatives had excellent antiviral competence toward tobacco mosaic virus (TMV) in vivo, especially compound A5 (median effective concentration [EC50] = 287.7 μg mL−1), which had a notable protective effect against TMV when compared with the commercial virucide ribavirin (EC50 = 622.0 μg mL−1). In addition, compound A17 had a protective efficiency of 84.3% at 200 μg mL−1 against Xac in plants. Given these outstanding results, the engineered title compounds could be regarded as promising leads for controlling plant virus and bacterial diseases. Preliminary mechanistic studies suggest that compound A5 could enhance the host's defense responses by increasing the activity of defense enzymes and upregulating defense genes, thereby suppressing phytopathogen invasion.

This research lays a foundation for the practical application of cinnamic acid derivatives containing diverse building blocks with alternative linking patterns in pesticide exploration. © 2023 Society of Chemical Industry.

Infectious diseases caused by viruses like HIV and SARS-COV-2 (COVID-19) pose serious public health threats. In search for new antiviral small molecules from chemically underexplored Hypericum species, a previously undescribed atropisomeric C8-C8' linked dimeric coumarin named bichromonol (1) was isolated from the stem bark of Hypericum roeperianum. The structure was elucidated by MS data and NMR spectroscopy. The absolute configuration at the biaryl axis was determined by comparing the experimental ECD spectrum with those calculated for the respective atropisomers. Bichromonol was tested in cell-based assays for cytotoxicity against MT-4 (CC₅₀ = 54 µM) cells and anti-HIV activity in infected MT-4 cells. It exhibits significant activity at EC₅₀ = 6.6-12.0 µM against HIV-1 wild type and its clinically relevant mutant strains. Especially, against the resistant variants A17 and EFV^R, bichromonol is more effective than the commercial drug nevirapine and might thus have potential to serve as a new anti-HIV lead.