Tritium-labelled 8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine ([<sup>3</sup>H]CPFPX), a potent and selective antagonist for the A<sub>1</sub>adenosine receptor
作者:Marcus H. Holschbach、Walter Wutz、Manfred Schüller、Dirk Bier、H.H. Coenen
DOI:10.1002/jlcr.679
日期:2003.3.30
The reduction of 1-allyl-8-cyclopentyl-3-(3-fluoropropyl)xanthine, 7, with tritium gas catalyzed by 10% Pd-C gave 8-cyclopentyl-3-(3-fluoropropyl)-1-[2,3-3H]propylxanthine ([3H]CPFPX), 8*, a potent and selective antagonist for the A1 adenosine receptor (A1AR). The synthesis of 7 proceeded from 6-aminouracil, 1, which underwent silylation and alkylation with allyl bromide to form 6-amino-3-allyluracil, 2. Nitrosation led to the 5-nitroso compound, 3, which underwent reduction to the 4,5-diaminouracil, 4, and carbodiimide-mediated acylation with cyclopentanecarboxylic acid produced 3-allyl-6-amino-5-cyclopentylcarboxamidouracil, 6. Alkylation at N−1 with 3-fluoro-1-bromopropane and cyclization with alkali completed the synthesis of 7. [3H]CPFPX had a radiochemical purity of > 98% and a specific activity of >2.1 TBq/mmol (57 Ci / mmol). [3H]CPFPX bound to the rat, pig and human A1AR with a KD of 0.63, 1.37 and 0.71 nM, respectively. The KD at the rat and human A2AAR was 812 and 940 nM, respectively, thus giving selectivities of >1200- and >700-fold. Copyright © 2003 John Wiley & Sons, Ltd.
在 10% Pd-C 催化下,1-烯丙基-8-环戊基-3-(3-氟丙基)黄嘌呤 7 被氚气还原,得到了 8-环戊基-3-(3-氟丙基)-1-[2,3-3H]丙基黄嘌呤([3H]CPFPX)8*,这是一种对 A1 腺苷受体(A1AR)有效的选择性拮抗剂。7 的合成由 6-氨基脲嘧啶 1 开始,经过硅烷化和与烯丙基溴的烷基化反应生成 6-氨基-3-烯丙基脲嘧啶 2,经过亚硝基化反应生成 5-亚硝基化合物 3,经过还原反应生成 4,5-二氨基脲嘧啶 4,再经过碳二亚胺介导的与环戊烷羧酸的酰化反应生成 3-烯丙基-6-氨基-5-环戊烷羧基氨基脲嘧啶 6。3H]CPFPX 的放射化学纯度大于 98%,比活度大于 2.1 TBq/mmol(57 Ci/mmol)。[3H]CPFPX与大鼠、猪和人A1AR的KD分别为0.63、1.37和0.71 nM。大鼠和人类 A2AAR 的 KD 分别为 812 nM 和 940 nM,因此选择性大于 1200 倍和大于 700 倍。Copyright © 2003 John Wiley & Sons, Ltd. All Rights Reserved.