(S)-3-Amino-4-(difluoromethylenyl)cyclopent-1-ene-1-carboxylic acid (OV329, 1) is being developed for the treatment of epilepsy and addiction. The previous 14-step synthesis of OV329 was low yielding, involved an unselective α-elimination to form the cyclopentene, required the use of tert-butyllithium, and produced toxic selenium byproducts in the penultimate step. A new synthesis, which avoids the aforementioned issues, was carried out on large scale, reducing the step count from 14 to 9 steps and increasing the overall yield from 3.7% to 8.1%.

中文翻译：

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γ-氨基丁酸氨基转移酶的强灭活剂（S）-3-氨基-4-（二氟亚甲基）-环戊-1-烯-1-羧酸（OV329）的合成

（小号）-3-氨基-4-（difluoromethylenyl）环戊-1-烯-1-羧酸（OV329，1）正被用于癫痫和成瘾的治疗的发展。先前的OV329的14步合成产率低，涉及非选择性的α-消除反应以形成环戊烯，需要使用叔丁基锂，并且在倒数第二步中产生了有毒的硒副产物。大规模进行了避免上述问题的新合成，将步骤数从14个步骤减少到9个步骤，并将总产率从3.7％增加到8.1％。