蛔虫駆除薬の研究 (第7報)

1-Benzyl-2-oxo-5-isopropyl-4-piperidineacetic Acidの合成

抄録

Hydrogenation of 1-benzyl-2-oxo-5-isopropyl-Δ^{4, α}-piperidine acetic acid (IV) with platinum oxide in methanol gave cis- and trans-1-benzyl-2-oxo-5-isopropyl-4-piperidine acetic acid (Xa and Xb). Xa was also obtained by hydrolysis and decarboxylation of diethyl trans-1-benzyl-2-oxo-5-isopropyl-4-piperidinemalonate (XIII), which was prepared by the Michael condensation of diethyl malonate and 1-benzyl-5-isopropyl-5, 6-dihydro-2(1H)-pyridone (XII) obtained from IV by hydrogenation with sodium borohydride and subsequent dehydration in the usual manner.
IV was prepared by acylation of I with half ester of malonyl chloride into ethyl 2-[(N-ethoxycarbonylacetylbenzylamino)methyl]isovalerate (II) and subsequent cyclization by the Dieckmann condensation, followed by hydrolysis and decarboxylation.