Two new metabolites from the endophytic fungus Xylaria sp. isolated from the medicinal plant Curcuma xanthorrhiza

Abstract The endophytic fungus Xylaria sp. was isolated from healthy leaves of Curcuma xanthorrhiza, collected on the island of Timor, Indonesia. Two new compounds (1 and 2), together with the known resacetophenone (3), were isolated and their structures were elucidated on the basis of comprehensive NMR and mass spectral analyses. The enantiomers of rac-1 were separated by chiral HPLC and their HPLC-ECD spectra were recorded to determine the absolute configuration on the basis of TDDFT-ECD calculations. The (3R,3aR, 9aR) absolute configuration of the optically active 2 was established by comparing the experimental solution ECD spectrum with the TDDFT ones computed for the gas phase and solu…