Nitro-benzylideneoxymorphone, a bifunctional mu and delta opioid receptor ligand with high mu opioid receptor efficacy oleh Keith M. Olson, Andrea L. Devereaux, Payal Chatterjee, Savanah L. Saldaña-Shumaker, Amanda Shafer, Adam Plotkin, Ram Kandasamy, Ram Kandasamy, Alexander D. MacKerell, John R. Traynor, John R. Traynor, Christopher W. Cunningham