Phenylphenalenones and oxabenzochrysenones from the Australian plant Haemodorum simulans.

Chemical investigation of the Australian plant Haemodorum simulans (Haemodoraceae) resulted in the isolation of two new phenylphenalenones, haemoxiphidone and haemodordioxolane from the bulbs together with the first report of an oxabenzochrysenone glycoside, haemodoroxychrysenose from the aerial parts of the plant. Also isolated were two previously described phenylphenalenones 5,6-dimethoxy-7-phenyl-1H,3H-naphtho[1,8-cd]pyran-1,3-dione and haemodorone and two oxabenzochrysenones 5-hydroxyl-2-methoxy-1H-naphtho[2,1,8-mna]xanthen-1-one and 5-methoxy-1H-naphtho[2,1,8-mna]xanthen-1-one. The X-ray structure of the phenylphenalenone 5,6-dimethoxy-7-phenyl-1H,3H-naphtho[1,8-cd]pyran-1,3-dione was secured for the first time. All compounds were deduced by detailed spectroscopic analyses. HPLC-NMR chemical profiling of an enriched fraction containing a mixture of haemodordioxolane and 5,6-dimethoxy-7-phenyl-1H,3H-naphtho[1,8-cd]pyran-1,3-dione facilitated the partial identification of these secondary metabolites. The structure previously assigned as xiphidone in our initial studies of this plant was re-assigned as the new isomer haemoxiphidone.