Polyhydroxylated sesquiterpenes and ergostane glycosides produced by the endophytic fungus Xylaria sp. from Azadirachta indica.

The investigation of the metabolites from the endophytic fungus Xylaria sp. YM 311647 in solid fermentation resulted in the isolation of six undescribed compounds, namely xylarioxides A-F, respectively. These included one eremophilane sesquiterpene, three guaiane sesquiterpene glycosides, and two ergostane glycosides. The structures of the compounds were determined by extensive analyses of spectroscopic data, including 1D and 2D NMR, as well as HRESIMS data. The stereochemistry of xylarioxide A was confirmed by X-ray crystallographic analysis. All of the isolated compounds were assayed for their antifungal activities against seven phytopathogenic fungi and two human pathogenic fungi. Among them, xylarioxides A, E and F showed potent activities against the tested phytopathogens. Particularly, xylarioxide E exhibited the highest activity against Gibberella saubinetii, Curvularia lunata, and Colletotrichum gloeosporioides with MIC values of 4, 4, and 8 µg/mL, respectively, which were comparable to the positive control of nystatin. Interestingly, guaiane sesquiterpene glycosides have been rarely reported from fungal sources. Additionally, xylarioxide E represented an unusual naturally occurring 3,4-seco-steroidal glycoside with a seven-membered lactone in ring A.

Structural data of highly luminescent lanthanide complexes constructed by bis-tridentate ligand and as sensor for Et2O.

In this data article, we present the structural and PXRD data of the lanthanide complexes constructed by bis-tridentate ligand tppz (2,3,5,6-tetra-2-pyridinylpyrazine). Detailed structure, luminescence and sensing properties were discussed in "highly luminescent lanthanide complexes constructed by bis-tridentate ligand and as sensor for Et2O" (Zheng et al., 2018). The data includes the structure of Tb-complex, PXRD of Tb-complex, and also detailed structure information listed in Table 1, Table 2, Table 3.