Ochracenes A–I, Humulane-Derived Sesquiterpenoids from the Antarctic Fungus <i>Aspergillus ochraceopetaliformis</i>

Nine new humulane-derived sesquiterpenoids, ochracenes A–I (<b>1</b>–<b>9</b>), were isolated from the Antarctic fungus <i>Aspergillus ochraceopetaliformis</i> SCSIO 05702. Their structures including absolute configurations were elucidated on the basis of spectroscopic analysis, Mosher’s method, and electronic circular dichroism analysis. Compared with previous humulane-type sesquiterpenoids, ochracenes A–I (<b>1</b>–<b>9</b>) featured novel carbon skeletons with corresponding methyl migration, ring cleavage, and carbon loss. Two unprecedented 8,9-secocyclic sesquiterpenoids (<b>2</b> and <b>3</b>) exhibited inhibitory effects on lipopolysaccharide-induced NO release in RAW 264.7 mouse macrophage cell lines with IC₅₀ values of 14.6 ± 0.5 and 18.3 ± 1.7 μM, respectively

Ultrahigh Lithium Selective Transport in Two-Dimensional Confined Ice

Inspired by selective ion transport in biological membrane proteins, researchers developed artificial ion channels that sieve monovalent cations, catering to the increasing lithium demand. In this work, we engineered an ion transport channel based on the confined ice within two-dimensional (2D) capillaries and found that the permselectivity of monovalent cations depends on the anisotropy of the confined ice. Particularly, the 2D confined ice showed an anomalous lithium selective transport along the (002) direction in the vermiculite capillary, with the Li+/Na+ and Li+/K+ permselectivity reaching up to 556 ± 86 and 901 ± 172, respectively, superior to most ion-selective channels. However, the 2D confined ice along the (100) direction showed less Li+ permselectivity. Additionally, the anisotropy of 2D confined ice can be tuned by adjusting the interlayer spacing. By providing insights into the ion transport in the 2D confined ice, our work may inspire more design of monovalent ion-selective channels for efficient lithium separation

Antifungal New Oxepine-Containing Alkaloids and Xanthones from the Deep-Sea-Derived Fungus <i>Aspergillus versicolor</i> SCSIO 05879

Phytopathogenic fungi remain a continuous and huge threat in the agricultural fields. The agrochemical industry has made great development of the use of microbial natural products, which has been regarded as an effective strategy against phytopathogenic fungi. Antifungal bioassay-directed fractionation was used to isolate two new oxepine-containing alkaloids (<b>1</b> and <b>2</b>), two new 4-aryl-quinolin-2-one alkaloids (<b>3</b> and <b>4</b>), and four new prenylated xanthones (<b>5</b>–<b>8</b>) from the deep-sea-derived fungus <i>Aspergillus versicolor</i> SCSIO 05879. Extensive NMR spectroscopic analysis, quantum mechanical calculations, and X-ray single-crystal diffraction were used to elucidate their structures, including their absolute configurations. Versicoloids A and B, versicone A, and cottoquinazoline A showed antifungal activities against three phytopathogenic fungi. The antifungal activities of these bioactive compounds strongly depend on the fungal species. Especially versicoloids A and B showed strong fungicidal effect (MIC of 1.6 μg/mL) against <i>Colletotrichum acutatum</i>, compared with that of the positive control cycloheximide (MIC of 6.4 μg/mL). The results of antifungal experiments indicated that versicoloids A and B may be regarded as candidate agents of antifungal agrochemicals