A new synthetic process was developed for (+)-2-((1R,2R,3R,5S)-2-amino-6,6-dimethylbicyclo[3.1.1]hept-3-yl)ethanol, a key intermediate of S-5751. Diastereoselective alkylation of (+)-nopinone with ethyl bromoacetate, formation of O-methyl oxime, and diastereoselective reduction with NaBH4−AlCl3 could be safely carried out. Stereochemistry of the (1R,2R,3R,5S)-6,6-dimethylbicyclo[3.1.1]heptane ring
开发了一种新的合成方法,用于(+)-2-((1 R,2 R,3 R,5 S)-2-
氨基-6,6-二甲基双环[3.1.1]庚-3-基)
乙醇, S-5751的关键中间体。可以安全地进行
溴乙酸乙酯的(+)-nopinone的非对映选择性烷基化,O-甲基
肟的形成以及NaBH 4 -AlCl 3的非对映选择性还原。讨论了(1 R,2 R,3 R,5 S)-
6,6-二甲基双环[3.1.1]庚烷环的立体
化学,以在这些反应上实现较高的非对映选择性。为了扩大规模,对NaBH的安全性进行了详细考虑4 -AlCl 3还原。