Synthesis of substituted pyrimido[4,5-b]
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Christophe Plisson; Jacques Chenault
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Article
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2001
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Journal of Heterocyclic Chemistry
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English
β 56 KB
## Abstract Ethyl 1βethylβ7βmethylβ4βoxoβ1,4βdihydro[1,8]naphthyridineβ3βcarboxylate (**1**), precursor of nalidixic acid, has been converted in two steps through ([1,8]naphthyridinβ3βyl)carbonylguanidine derivatives into substituted pyrimido[4,5β__b__] and [5,4β__c__][1,8]naphthyridines.