Gillings N M, Gee A D, Inoue O
PET Centre, Aarhus University Hospital, Denmark.
Appl Radiat Isot. 1999 Apr;50(4):707-14. doi: 10.1016/s0969-8043(98)00137-7.
In an attempt to elucidate the contribution of the extent of nitrogen protonation on the in vivo binding of methamphetamine in the brain, the enantiomers of [N-methyl-11C]beta, beta-difluoroamphetamine (4) were prepared for use in positron emission tomography (PET) studies. Thus, the enantiomers of beta, beta-difluoroamphetamine were prepared from trans-beta-methylstyrene, via bromination, conversion into the azirine, fluorination and resolution as the tartrate salts. (R)- and (S)-beta, beta-difluoroamphetamine (3) were then each labelled with carbon-11 (tt/2 = 20.4 min) by N-methylation of the corresponding homochiral beta, beta-difluoroamphetamine with [11C]methyl iodide. The labelled products were each synthesised, purified and formulated in 35 min, starting from [11C]carbon dioxide in 15-16% decay-corrected radiochemical yield, with a radiochemical purity of > 99% and specific radioactivity of 50-150 GBq mumol-1 at end of synthesis.
为了阐明氮质子化程度对甲基苯丙胺在脑内体内结合的贡献，制备了[ N -甲基- 11 C]β,β-二氟苯丙胺（4）的对映体用于正电子发射断层扫描（PET）研究。因此，β,β-二氟苯丙胺的对映体由反式-β-甲基苯乙烯经溴化、转化为氮丙环、氟化以及作为酒石酸盐拆分制备而成。然后，通过用[ 11 C]甲基碘对相应的同手性β,β-二氟苯丙胺进行N -甲基化，将（R）-和（S）-β,β-二氟苯丙胺（3）分别用碳- 11（半衰期= 20.4分钟）进行标记。从[ 11 C]二氧化碳开始，在35分钟内合成、纯化并配制标记产物，衰变校正后的放射化学产率为15 - 16%，放射化学纯度> 99%，合成结束时比活度为50 - 150 GBq μmol - 1。
