1. Beijing National Laboratory for Molecular SciencesKey Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of Sciences Beijing 100190 P. R. China
2. College of ChemistryUniversity of Chinese Academy of Sciences Beijing 100049 P. R. China
3. State Key Laboratory of Membrane Biology, Institute of ZoologyChinese Academy of Sciences Beijing 100101 P. R. China