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Brasofensine (NS-2214, BMS-204756) is a phenyltropane that had been under development for the treatment of Parkinson's and Alzheimer's disease. Phase II trials were conducted in 1996 and brasofensine was shown to be both effective and well tolerated at a dose of 4 mg, however development was stopped after ''in vivo'' cis-anti isomerization of the 2α-methyloxime group was reported. In animal models of Parkinson's disease, brasofensine was effective in stimulating LMA and reversing akinesia. The isomerization of brasofensine is not between the alpha and beta positions on the 2 position of the tropane ring but rather the E/Z isomerization of the imine (i.e. "methyl-aldoxime"). It was believed that this process occurs in vivo although it cannot be ruled out as a possibility that some isomerization also occurs prior to ingestion. The (''Z'')-isomer has been consigned the name BMS-205912 In PD, symptoms do not begin to manifest until there has been an 80% reduction in dopaminergic neurons, particularly in the substantia nigra brain region. ==Metabolism and distribution== NS-2214 is not particularly stable and is readily metabolized. 50 mg was the dosage that was tried on humans, although the starting dose was 2 mg.〔 Interestingly, because rats metabolism is much greater than humans, the amount of metabolites detected in their urine (and feces) was also much greater than for humans, who excrete more of the product intact. For humans, most (~90%) of the 14C was detected in the urine, whereas for rats as much as 80% of the 14C was in their feces. It is well known that a Schiff base is more stable than a regular imine. Imine formation is a reversible process, and in the study by Zhu et al.,〔 none of the aldehyde was recovered/detected by GC-MS. Instead, the breakdown products were N-demethyl metabolites. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Brasofensine」の詳細全文を読む スポンサード リンク
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