Penisimplicins A and B: Novel Polyketide-Peptide Hybrid Alkaloids from the Fungus Penicillium simplicissimum JXCC5.

In this study, two previously undescribed nitrogen-containing compounds, penisimplicins A (1) and B (2), were isolated from Penicillium simplicissimum JXCC5. The structures of 1 and 2 were elucidated on the basis of comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS data. The absolute configuration of 2 was determined by Marfey's method, ECD calculation, and DP4+ analysis. Both structures of 1 and 2 feature an unprecedented manner of amino acid-derivatives attaching to a polyketide moiety by C-C bond. The postulated biosynthetic pathways for 1 and 2 were discussed. Additionally, compound 1 exhibited significant acetylcholinesterase inhibitory activity, with IC50 values of 6.35 µM.

Structurally diverse limonoids and bio-active evaluation from Trichilia connaroides.

Four new limonoids, named as trichiconlide G (1), 2-hydroxyltrijugin F (2), 23-oxo-21-hydroxyltrijugin F (3), 21-oxo-23-hydroxyltrijugin F (4), along with sixteen known analogues (5-20) were isolated from the leaves and twigs of Trichilia connaroides. Their structures and absolute configurations were determined by spectroscopic analyses, X-ray diffraction analysis, and TD-DFT-ECD calculations. Trichiconlide G (1) is one rare naturally occurring 1,2-seco phragmalin-type limonoid bearing a C-7/28 δ-lactone ring. Additionally, 2-hydroxyltrijugin F (2), 23-oxo-21-hydroxyltrijugin F (3), and 21-oxo-23-hydroxyltrijugin F (4) are three naturally occurring limonoids with a rare C-16/8 δ-lactone ring. All isolates were evaluated for their cytotoxic and anti-inflammatory activities. None of compounds exhibited cytotoxicity against five human cancer cell lines A-549, HepG2, 5-8F, Siha, and SCC-4 at the concentration of 40 µM. Compounds 16 and 17 showed moderate anti-inflammatory activity with IC50 values of 28.45 ± 2.51 and 22.66 ± 2.01 µM, respectively.

Kalshinoids A-F, Anti-inflammatory Sesquiterpenes from Kalimeris shimadae.

In a study of the potential anti-inflammatory constituents from Kalimeris shimadae, six new sesquiterpenes, kalshinoids A-F (1-6), together with 21 known compounds (7-27), were isolated. The structures and absolute configurations of the new compounds were discerned from extensive spectroscopic analysis, and the absolute configurations of kalshinoids A, B, E, and F were established by ECD calculations. Furthermore, the identified compounds were tested for anti-inflammatory activity as assessed by inhibition of tumor necrosis factor-alpha (TNF-α) in THP-1 cells. Three sesquiterpenes [kalshinoid F, 4(15)-eudesmen-1ß,7,11-triol, and 4α,10α,11-trihydroxy-1ßH,5ßH-guai-7(8)-ene] reduced levels of TNF-α in lipopolysaccharide-stimulated THP-1 cells in a concentration-dependent manner and were more potent than dexamethasone. These natural sesquiterpenes merit further investigation as possible anti-inflammatory agents.

Irpeksins A-E, 1,10- seco-Eburicane-Type Triterpenoids from the Medicinal Fungus Irpex lacteus and Their Anti-NO Activity.

Five new triterpenoids, irpeksins A-E (1-5), were isolated from fruiting bodies of the medicinal fungus Irpex lacteus. The structures as well as absolute configurations of the new compounds were established via extensive spectroscopic analysis, computational methods, and Cotton effects. Compounds 1-4 are featured by a scaffold of 1,10- seco- and ring B aromatic eburicane (24-methyllanostane), and compound 5 is characterized by a scaffold of 1,10-9,11- diseco- and ring B aromatic eburicane, which represents unprecedented cleavage patterns in the lanostane family. Compounds 1-5 showed significant inhibitory activity against NO production in LPS-activated RAW 264.7 macrophage cells with IC50 values varying from 2.2 to 19.6 µM.

Anti-Proliferative and Anti-Inflammatory Lanostane Triterpenoids from the Polish Edible Mushroom Macrolepiota procera.

This study features the isolation and identification of 12 lanostane-type triterpenoids, namely lepiotaprocerins A-L, 1-12, from the fruiting bodies of the Poland-collected edible mushroom Macrolepiota procera. The structures and the absolute configurations of the new compounds were ambiguously established by extensive spectroscopic analyses, ECD calculation, and single-crystal X-ray diffraction analyses. Structurally, lepiotaprocerins A-F, 1-6, are distinguished by the presence of a rare "1-en-1,11-epoxy" moiety which has not been previously described in the lanostane class. Biologically, lepiotaprocerins A-F, 1-6, displayed more significant inhibitions of nitric oxide (NO) production than the positive control L- NG-monomethyl arginine (L-NMMA) (IC50 47.1 µM), and lepiotaprocerins G-L, 7-12, showed various cytotoxicity potencies against a panel of human cancer cell lines. Compound 9 also displayed antitubercular activity against Mycobacterium tuberculosis H37Ra with a minimal inhibitory concentration (MIC) 50 µg/mL.

Miscellaneous lanostane triterpenoids with cytotoxicities from fruiting bodies of the basidiomycete Stereum sp.

Ten new highly oxygenated lanostane triterpenoids, stereinones A-J (1-10), were isolated from the fruiting bodies of the basidiomycete Stereum sp. Compounds 3 and 4 are structurally characterized as intact lanostane-type triterpenoids containing unusual 1,2-diketone functionality at C-11 and C-12, while compound 10 is a 24-methylene-lanostane. The structures of these new compounds were established based on detailed 1D and 2D NMR spectroscopic analyses, along with quantum chemical NMR calculations. All isolates were evaluated for their in vitro cytotoxicities against five human tumor cell lines (including HL-60, A-549, SMMC-7721, MCF-7, and SW480 cell lines). Compound 4 showed moderate cytotoxic activities against tumor cell lines SMMC-7721 and SW480 with IC50 values of 9.1 and 9.8µM, respectively.

Lanostane triterpenoids from fruiting bodies of basidiomycete Stereum sp., structures and biological activities.

Twelve new lanostane triterpenoids, sterenoids A-L (1-12) have been isolated from fruiting bodies of the basidiomycete Stereum sp. Compounds 1-12 are rare 14(13→︀12)abeo-lanostane triterpenoids featuring remarkable 13R configurations that discriminate from the previously covered counterparts. Their structures and absolute configurations are assigned on the basis of in-depth one- and two-dimensional NMR spectroscopic analysis, as well as unbiased quantum chemical NMR and electronic CD calculations. All isolates are evaluated for their in vitro cytotoxicity against five human tumor cell lines. Compound 5 exhibits potent cytotoxic activities against tumor cell lines HL-60 and SMMC-7721 with IC50 values of 4.7 and 7.6 µM, respectively.