Improved synthesis of [18F]fluoromethyl tosylate, a convenient reagent for radiofluoromethylations
作者:Timothy R. Neal、Scott Apana、Marc S. Berridge
DOI:10.1002/jlcr.949
日期:2005.7
The utility of [18F]fluoromethyl tosylate as an [18F]fluoromethylation reagent has been reexamined. The preparation of this potentially useful compound from the reaction of bis(tosyloxy) methane with 18F- was reported several years ago, but it had not found use as a labeling reagent. When the reported reaction of bis(tosyloxy) methane with 18F- was carried out, [18F]fluoromethyl tosylate was formed along with [18F]tosyl fluoride. The product ratio depended upon reaction conditions, with the yield of [18F]fluoromethyl tosylate usually in the range of 25–40%. Addition of a small amount of water to the reaction mixture resulted in a significant increase in the yield of [18F]fluoromethyl tosylate. Reaction conditions were defined that produced a yield of 71±6% of [18F]fluoromethyl tosylate (decay corrected). The product was conveniently purified by alumina chromatography. Reaction of [18F]fluoromethyl tosylate with the (des-fluoromethyl) fluticasone propionate thioacid precursor produced [18F]fluticasone propionate in improved yield (16%, from fluoride in production-scale runs) over other synthesis methods. Similarly, formation of [18F]choline, [18F]fluoromethionine and N-([18F]fluoromethyl)spiperone from the reaction of [18F]fluoromethyl tosylate with corresponding precursors was examined. Copyright © 2005 John Wiley & Sons, Ltd.
[18F]氟甲基磺酸酯作为[18F]氟甲基化试剂的实用性被重新审视。几年前,报道了从双(磺酰氧)甲烷与18F-反应制备这种潜在有用化合物的研究,但它并未被用作标记试剂。当进行双(磺酰氧)甲烷与18F-的反应时,生成了[18F]氟甲基磺酸酯以及[18F]磺酰氟。产品比例取决于反应条件,通常[18F]氟甲基磺酸酯的产率在25-40%范围内。在反应混合物中加入少量水显著提高了[18F]氟甲基磺酸酯的产率。已经定义出了生产[18F]氟甲基磺酸酯的反应条件,其产率为71±6%(衰变校正)。该产品通过铝土矿色谱法方便地进行了纯化。[18F]氟甲基磺酸酯与(去氟甲基)氟替卡松丙酸的硫酸酯前体反应,产生了改进产率的[18F]氟替卡松丙酸(产率为16%,来源于生产规模中的氟化物),优于其他合成方法。同样,研究了[18F]氟甲基磺酸酯与相应前体反应生成[18F]胆碱、[18F]氟甲硫氨酸及N-([18F]氟甲基)吡哌酮。版权所有 © 2005 John Wiley & Sons, Ltd.