1. National Engineering Research Center for Biomaterials Sichuan University Chengdu 610064 P. R. China
2. Laboratory of Anesthesiology and Critical Care Medicine Department of Anesthesiology Translational Neuroscience Center West China Hospital Sichuan University Chengdu Sichuan Chengdu 610041 P. R. China
3. Institute of Organic Chemistry Johannes Gutenberg‐University Mainz Duesbergweg 10‐14 55099 Mainz Germany