Absolute Stereostructures of Paeonisothujone, a Novel Skeletal Monoterpene Ketone, and Deoxypaeonisuffrone, and Isopaeonisuffral, Two New Monoterpenes, from Moutan Cortex.

Three new labile monoterpenes named paeonisothujone, deoxypaeonisuffrone, and isopaeonisuffral were isolated from Chinese Moutan Cortex, the root cortex of Paeonia suffruticosa ANDREWS. The absolute stereostructures of paeonisothujone, deoxypaeonisuffrone, and isopaeonisuffral were elucidated on the basis of chemical and physicochemical evidence which included the application of the modified Mosher's method. Paeonisothujone is the first natural example of ortho-menthane type monoterpene having a cyclopropane ring.