Cis-3,5-dimethyl-3,5-piperidinedicarboxylic Acid (3) and several of its derivatives have been synthesized starting from 3,5-pyridinedicarboxylic acid. The ¹H NMR spectra indicate that these compounds assume a single conformation having the two carbonyl substituents in axial positions.

中文翻译：

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顺式-3,5-二甲基-3,5-哌啶二羧酸，肯普氏三酸的氨基二酸变体

顺式-3，5-二甲基-3，5-哌啶二羧酸（3）及其几种衍生物是从3，5-吡啶二甲酸开始合成的。的¹ 1 H NMR光谱表明，这些化合物假定具有轴向位置上的两个取代基羰基的单个构象。