Synthesis of the cardiotonic agent 14C-loprinone.
作者:Motosuke Yamanaka、Shinji Suda、Kyoichi Tadano
DOI:10.1002/jlcr.2580310208
日期:1992.2
14C-Labeled 1,2-dihydro-5-imidazo [1,2-a]pyridin-6-yl-6-methyl-2-oxo-3-pyridinecarbonitrile hydrochloride monohydrate 6 was synthesized in 5 steps from 6-bromoimidazo [1,2-a] pyridine using [2-14C] cyanoacetamide as the source of the radiolabel. The key intermediate, 1-imidazo [1,2-a] pyridin-6-yl-2-propanone 3 was prepared by the selective ozonolysis of the propenyl group of 6-(2-methylpropen-3-yl) imidazo [1,2-a] pyridine 2 under acidic conditions followed by the reduction with sodium sulfite. The chemical yield of 6 from 4-dimethylamino-3-imidazo-[1,2-a]pyridin-6-yl-3-buten-2-one 4 and the radiochemical yield from [2-14C] cyanoacetamide were both 57%. The radiochemical purity and the specific activity of 6 were 98% and 1868.5 MBq/mmol, respectively.
14C标记的1,2-二氢-5-咪唑[1,2-a]吡啶-6-基-6-甲基-2-氧代-3-吡啶碳腈盐酸盐一水合物6通过5步反应从6-溴咪唑[1,2-a]吡啶合成,使用[2-14C]氰基乙酰胺作为放射性标记源。关键中间体,1-咪唑[1,2-a]吡啶-6-基-2-丙酮3通过酸性条件下6-(2-甲基丙烯-3-基)咪唑[1,2-a]吡啶2的丙烯基团选择性臭氧氧化后用硫酸钠还原制备。从4-二甲氨基-3-咪唑-[1,2-a]吡啶-6-基-3-丁烯-2-酮4到6的化学产率和从[2-14C]氰基乙酰胺的放射化学产率均为57%。6的放射化学纯度和比活度分别为98%和1868.5 MBq/mmol。