海人草有効成分ならびに関連化合物の研究 第75報

2-Carboxy-4-allyl (およびpropenyl)-3-pyrrolidineacetic Acidsの合成ベタインの新熱分解 (4)

抄録

Ethyl 2-oxo-5-(2-dimethylaminopropyl)-4-piperidineacetate (I) was derived to its 3, 3-dichloride (III) by the application of sulfuryl chloride and thionyl chloride and a pyrrolinecarboxylic acid derivative (IV) was obtained by boiling (III) in barium hydroxide solution. Ethyl 1, 2-diethoxycarbonyl-4-(2-dimethylaminopropyl)-3-pyrrolidineacetate (VI) was obtained from a proline derivative formed by reducution of (IV). Treatment of the methiodide of (VI) was found to effect rapid betainization and pyrolysis of this betaine under a reduced pressure was found to result in the formation of a mixed basic methyl and ethyl esters (VII) and a mixed unsaturated methyl and ethyl esters (VIII). Reaction mechanism of this new pyrolysis of betaine was presumed. Saponification of (VIII) afforded 2-carboxy-4-allyl-(and -propenyl)-3-pyrrolidineacetic acids.