This manuscript depicts efficient synthesis of structurally novel morpholine amino acids, (1S,4S)-2-oxa-5-azabicyclo[2.2.1]heptane-4-carboxylic acid (+)-1, its enantiomer (−)-1, and racemic (endo)-5-oxa-2-azabicyclo[2.2.1]heptane-3-carboxylic acid (±)-2, which could serve as compact modules in medicinal chemistry to potentially modulate physicochemical and pharmacokinetic properties of drug candidates, and to introduce intellectual properties.

中文翻译：

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作为药物化学紧凑模块的桥连双环吗啉氨基酸的合成

这份手稿描述了结构新颖的吗啉氨基酸的有效合成，(1S,4S)-2-oxa-5-azabicyclo[2.2.1]heptane-4-羧酸 (+)-1，它的对映异构体 (-)-1，和外消旋 (endo)-5-oxa-2-azabicyclo[2.2.1]heptane-3-羧酸 (±)-2，可作为药物化学中的紧凑模块，潜在地调节候选药物的理化和药代动力学特性，并引进知识产权。