Bioassay-Guided and DeepSAT-Driven Precise Mining of Monoterpenoid Coumarin Derivatives with Antifeedant Effects from the Leaves of Ailanthus altissima.

Demand for the exploration of botanical pesticides continues to increase due to the detrimental effects of synthetic chemicals on human health and the environment and the development of resistance by pests. Under the guidance of a bioactivity-guided approach and HSQC-based DeepSAT, 16 coumarin derivatives were discovered from the leaves of Ailanthus altissima (Mill.) Swingle, including seven undescribed monoterpenoid coumarins, three undescribed monoterpenoid phenylpropanoids, and two new coumarin derivatives. The structure and configurations of these compounds were established and validated via extensive spectroscopic analysis, acetonide analysis, and quantum chemical calculations. Biologically, 5 exhibited significant antifeedant activity toward the Plutella xylostella. Moreover, tyrosinase being closely related to the growth and development of larva, the inhibitory potentials of 5 against tyrosinase was evaluated in vitro and in silico. The bioactivity evaluation results highlight the prospect of 5 as a novel category of botanical insecticide.

Eight structurally diverse components with anti-acetylcholinesterase activity from Daphne bholua.

Eight structurally diverse components, including six undescribed ones, (±)-daphuarin A (1a/1b), daphuarin B (2), daphuarin D-E (4-6), together with a pair of new natural products (±)-daphuarin C (3a/3b) were isolated from the herb of Daphne bholua Buch.-Ham. ex D. Don. Their planar structures were elucidated by extensive spectroscopic analyses. The configurations were established with the assistance of quantum chemical calculations, together with the Custom DP4+ method. The inhibitory potentials of all isolates against acetylcholinesterase were evaluated.

Rapid screening of diarylpentanoids from Daphne bholua.

Fractionation motivated by biological activity screening and NMR characteristic signals analysis led to the isolation of seventeen diarylpentanoids from the whole plant of Daphne bholua Buch.-Ham. ex D. Don, among which nine compounds were undescribed. Their structures and stereochemistry were determined by comprehensive spectroscopic data, J-based configurational analysis, and quantum chemical calculations. The inhibitory potentials of all isolates against acetylcholinesterase were evaluated in vitro and in silico.

Guaiane-type sesquiterpenoids with various ring skeletons from Daphne bholua uncovered by molecular networking and structural revisions of previously reported analogues.

The genus Daphne is a treasure-house of secondary metabolites with various biological effects, which inspired Daphne bholua being fully investigated phytochemically and biologically for the first time. Here, seven undescribed guaiane-type sesquiterpenoids (1-7) along with thirteen known analogues (8-20) were targeted and isolated from D. bholua using molecular networking. Their chemical structure and configurations were established via NMR spectroscopy analysis, NMR and ECD calculations, Snatzke's method, along with single-crystal X-ray diffraction technique. Moreover, two pairs of sesquiterpene isomers, either with prominent biological properties or with unprecedented skeleton, were revised by means of computer-assisted structure elucidation, chemical shift calculator using deep learning, etc. The inhibitory potentials of all isolates against acetylcholinesterase were evaluated in vitro and in silico.