Determination of a new chromone from Aurantii Fructus Immaturus by DFT/GIAO method

Investigation of EtOAc fraction from the 95% ethanol extract of Aurantii FructusImmaturus led to the isolation of one new chromone (1) and seven known flavonoids (2–8). Their structures were elucidated mainly by NMR and HR-ESI-MS, as well as on comparison with the reported NMR data. The final substituent pattern of 1 was defined by comparison of ¹³C NMR data calculated by DFT/GIAO with those of experimental NMR data.