著者

佐伯 清太郎 山下 絢子 盛中 泰洋 浜名 政和

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.25, no.1, pp.79-86, 1977-01-25 (Released:2008-03-31)

被引用文献数

1 2

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1, 1-Ethylenedioxy-9-(2-pyridyl) quinolizidine (1) was converted to N-ethoxycarbonylpyridinium salt (3) via monohydrobromide (2) by successive treatment with ammonium bromide and ethyl bromoacetate. The reaction of 3 with hydrochloric acid was markedly affected with the concentration of the acid. Thus, when 3 was heated with 15-20% hydrochloric acid, ring closure took place accompanied by hydrolysis of the ketal and ester groups and also decarboxylation to give 17-hydroxy compound (4). Heating with triethylamine gave dehydrated pyridinium salt (5) which was reduced with sodium borohydride and then catalytically to dl-allomatridine (6). On the other hand, heating 3 with 5-10% hydrochloric acid gave a carboxylic acid (9) which was also transformed into 6 through an ester (10) and a ring closure product (11) as shown in Chart 2. The action of 30% acid on 3 followed by the similar treatments afforded 1-hydroxy-9-(2-pyridyl) quinolizidine (7). Transformation of 1 to 17-hydroxyallomatridine (8) was further achieved successively by hydrolysis to 1-oxo compound (12), formation of its cyanohydrin (13) and hydrogenation over Raney nickel.