1. Department of Medicinal ChemistrySchool of PharmacyFudan University Shanghai 201203 China
2. Key Laboratory of Receptor Research, ShanghaiInstitute of Materia MedicaChinese Academy of Sciences 555 Zu Chong Zhi Road Shanghai 201203 China
3. University of Chinese Academy of Sciences No.19A Yuquan Road Beijing 100049 China