摘要 |
1,8-Naphthyridine compounds and a process for preparing chelated 1,8-naphthyridine derivatives and 1,8-naphthyridine derivatives which are pharmacautically useful compounds. Chelated 1,8-naphthyridine derivatives of the general formula [I]: <IMAGE> [I] wherein X and Y are independently a lower alkyl group, are prepared by subjecting a compound of the general formula [II]: <IMAGE> [II] wherein X and Y are as defined above and R is a lower alkyl group, to ring-closing condensation in the presence of boron trifluoride and/or a boron trifluoride complex at an elevated temperature, and 1,8-naphthyridine derivatives of the general formula [III]: <IMAGE> [III] wherein X and Y are as defined above, are prepared by treating the chelated 1,8-naphthyridine derivatives with water and/or an alcohol. The desired products can be readily obtained in high yields. The chelated compounds are novel compounds.
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