Xylariaides A and B, novel cytochalasans with a unique 5/6/5/3 ring system from a soil fungus Xylaria sp. Y01
Yi-Yun Yuan, Yan Li, Wen-Yu Lu, Ai-Lin Liang, Jing Li, Wen‐Xuan Wang
Abstract
Abstract Two new cytochalasans, xylariaides A ( 1 ) and B ( 2 ), were isolated and identified from a soil fungus Xylaria sp. Y01. Their structures were unambiguously determined by extensive spectroscopic methods including high resolution electrospray ionization mass spectrometry, ultraviolet radiation, infrared spectroscopy, and 1D/2D NMR, as well as in-depth quantum chemical calculations of gauge-including atomic orbital (GIAO) 13 C NMR chemical shifts, electronic circular dichroism (ECD), and spin–spin coupling constants. The unprecedented core structure with a 5/6/5/3 fused tetracyclic ring system further enriches the scaffold types of cytochalasans. Graphical Abstract
Topics & Concepts
ChemistryRing (chemistry)Circular dichroismVibrational circular dichroismElectrospray ionizationMass spectrometrySpectroscopyCoupling constantQuantum chemicalComputational chemistryStereochemistryCrystallographyOrganic chemistryPhysicsMoleculeParticle physicsChromatographyQuantum mechanicsMicrobial Natural Products and BiosynthesisMicrobial Community Ecology and PhysiologyGenomics and Phylogenetic Studies