摘要
A pair of alkaloid enantiomers possessing a novel 1-oxaspiro[4.4]non-3-ene-2,7-dione skeleton,trichodermotin A(1),was obtained from the fungus Trichoderma asperellum.Spectroscopic data,X-ray diffraction,and ECD calculations were used to establish its structure and absolute configuration.(−)-1 showed significantα-glucosidase inhibitory activity(IC_(50)=10.1μmol/L vs.60.1μmol/L of positive control).A plausible biosynthetic pathway originating from L-β-phenylalanine was proposed,and a facile total synthesis was further accomplished.The key reaction of our synthetic strategy was a domino aza-Michael/lactonization in one pot,leading to the pivotal 4-amino-oxaspiro[4.4]octane scaffold.
基金
supported by the Program for Changiiang Scholars of Ministry of Education of the People's Republic of China(No.T2016088)
the National Natural Science Foundation for Distinguished Young Scholars(No.81725021)
the National Natural Science Foundation for Excellent Young Scholars(No.81922065)
the Innovative Research Groups of the National Natural Science Foundation of China(No.81721005)
the National Natural Science Foundation of China(No.81903461)
the Science and Technology Major Project of Hubei Province(No.2021ACA012)
the Research and Development Program of Hubei Province(No.2020BCA058)
the Fundamental Research Funds for the Centural Universities(No.2019kfyXJJS168).