 La Clair in 2006, purporting a synthesis of Gräfe's proposed structure based on 1H nuclear magnetic resonance (NMR) spectra.Natural products chemist Scott D. Rychnovsky simulated the 13C nuclear magnetic resonance spectrum of the structure proposed by Gräfe and found that it did not correspond to the spectrum of the structure allegedly synthesized by La Clair.Rychnovsky proposed a different structure (1) based on panepophenanthrin, another molecule isolated from a different strain of "P. rudis".