New compounds from the essential oil ofVetiveria nigritana roots from Mali

Chemical Constituents of the Mushroom Dictyophora indusiata and Their Anti-Inflammatory Activities

As an edible and medicinal fungus, Dictyophora indusiata is well-known for its morphological elegance, distinctive taste, high nutritional value, and therapeutic properties. In this study, eighteen compounds (1-18) were isolated and identified from the ethanolic extract of D. indusiata; four (1-4) were previously undescribed. Their molecular structures and absolute configurations were determined via a comprehensive analysis of spectroscopic data (1D/2D NMR, HRESIMS, ECD, and XRD). Seven isolated compounds were examined for their anti-inflammatory activities using an in vitro model of lipopolysaccharide (LPS)-simulated BV-2 microglial cells. Compound 3 displayed the strongest inhibitory effect on tumor necrosis factor-α (TNF-α) expression, with an IC₅₀ value of 11.9 μM. Compound 16 exhibited the highest inhibitory activity on interleukin-6 (IL-6) production, with an IC₅₀ value of 13.53 μM. Compound 17 showed the most potent anti-inflammatory capacity by inhibiting the LPS-induced generation of nitric oxide (NO) (IC₅₀: 10.86 μM) and interleukin-1β (IL-1β) (IC₅₀: 23.9 μM) and by significantly suppressing induced nitric oxide synthase (iNOS) and phosphorylated nuclear factor-kappa B inhibitor-α (p-IκB-α) expression at concentrations of 5 μM and 20 μM, respectively (p < 0.01). The modes of interactions between the isolated compounds and the target inflammation-related proteins were investigated in a preliminary molecular docking study. These results provided insight into the chemodiversity and potential anti-inflammatory activities of metabolites with small molecular weights in the mushroom D. indusiata.

Essential oil of the malagasy grass Elionurus tristis Hack. contains several undescribed sesquiterpenoids

Essential oils (EOs) obtained from aerial parts and roots of Elionurus tristis were investigated by GC, GC-MS, pc-GC and NMR. Both aerial parts and roots EOs contained common molecules such as α-pinene, camphene, trans-α-bergamotene and calarene. Moreover, we identified several unusual sesquiterpenes and four undescribed compounds, 7-epi-khusian-2-ol, 4,8-di-epi-acorone, 2-epi-ziza-5-en-2-ol and antsorenone. The last one exhibits an undescribed natural sesquiterpene skeleton. All undescribed compounds were isolated and fully characterized by MS, 1D and 2D-NMR. Furthermore, the formation pathway of the Antsorane skeleton is discussed.

Decarboxylation Facilitated by Carbocation Formation and Rearrangement during Steam Distillation of Vetiver Oil

Density functional theory (DFT) calculations are used to probe the validity of mechanistic proposals for the conversion of isozizanoic acid to 12-norisoziza-5-ene, a reaction that occurs during steam distillation of vetiver oil. While this conversion corresponds overall to a simple decarboxylation, a multistep mechanism involving carbocation intermediates is supported by the computational results.

Natural sesquiterpenoids

This review covers the isolation, structural determination, synthesis and chemical and microbiological transformations of natural sesquiterpenoids. 423 references are cited.