From a Single Aliphatic Substrate

This unlikely type of synthesis is represented by the reduction of 5,6-dimethyl-5,6-dinitrodecane-2,9-dione (1) to give a mixture from which 2,4a,6,8a-tetramethyl-3,4,4a,7,8,8a-hexahydro-l,5-naphthyridine 1,5-dioxide (2) was isolated via its picrate (Zn, NH4 Cl, H20, EtOH, 20°C, 6h %) 1022 the structural configuration of the foregoing compound and related products were studied later,196 

An essentially similar type of reaction has been used to prepare fused 1,5-naphthyridines such as 2,8-dimethyl-6,12-bis(p-tolylimino)-5,6,ll,12-tetrahydrodi-benzo[ , g][l,5]-naphthyridine (3).688 

The Naphthyridines The Chemistry of Heterocyclic Compounds, Volume 63, by D.J. Brown Copyright 2008 John Wiley Sons, Inc. 

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