(3R,6R)-4-Methyl-6-(1-methylethyl)-3-phenylmethyl-perhydro-1,4-oxazine-2,5-dione: An Apoptosis-Inducer from the Fruiting Bodies of Isaria japonica

(3R,6R)-4-Methyl-6-(1-methylethyl)-3-phenylmethylperhydro1,4-oxazine-2,5-dione (1) was isolated from the fruiting bodies of Isaria japonica as an apoptosis-inducing agent. The complete structural assignment of the compound was accomplished on the basis of spectroscopic methods and chemical transformations. Compound 1 induced apoptotic cell death of the human leukemia cells (HL-60) in a dose-dependent manner, ranging from 5.0 μg/ml to 100.0 μg/ml.