title: Unique spirocyclopiperazinium salt. Part 4: modification of dispirocyclopiperazinium (DSPZ) salts as analgesics.
abstract: In order to improve the analgesic activity of lead compound 7a, two series of dispirocyclopiperazinium (DSPZ) salts 9a-h, 10a-e and compounds 14, 15 were synthesized and evaluated for their in vivo analgesic activity both by acetic acid induced writhing test and hot plate test. Compounds 9h, 14, and 15 exhibited better analgesic activities than 7a. Several important structure-activity relationships were revealed from this study: (1) the introduction of aryl group would obviously improve the activity; (2) it was favorable to enhance the analgesic activity and reduce the toxicity to incorporate alkyl group with suitable length in the molecule; (3) carbamate analogues displayed lower toxicity than carboxylic ester analogues; (4) hydroxylation and chlorination of lead compound could increase the analgesic activity in hot plate test.
authors.affiliation: Department of Chemical Biology, School of Pharmaceutical Sciences, Peking University, Beijing 100083, PR China.
authors.forename: Ang
authors.initials: A
authors.lastname: Li
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Cai-Qin
authors.initials: CQ
authors.lastname: Yue
authors.forename: Jia
authors.initials: J
authors.lastname: Ye
authors.forename: Chang-Ling
authors.initials: CL
authors.lastname: Li
authors.forename: Run-Tao
authors.initials: RT
authors.lastname: Li
mesh_terms: D000700:Analgesics / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D051379:Mice; D010879:Piperazines / Q000737:chemistry* / Q000494:pharmacology; D012492:Salts
chemical_list: D000700:Analgesics; D010879:Piperazines; D012492:Salts