3-Nitro-2-phenyl-l,7-naphthyridine

In this method the nitro group in the aliphatic nitro compound is usually present on a carbon atom, which is also activated by CO-functioiiality (aldehyde, ester, arylketoiie). A successful application of this method is the Borsche modification of the Friedlander synthesis, involving condensation of A-(3-amino-4-picolylidene)-p-toluidine (17) with [Pg.289]

Hydroxy-/V-methyl-2-oxo- 1-phenyl-1,2-dihydro- 1,8-naphthyridine-3-carboxamide 4- Hydroxy-7- methyl-3-pentyl-1,8-naphthyridin-2(l//)-one 4-Hydroxy-3-methyl-1 -phenyl-1,8-naphthyridin-2(l//)-one 4-Hydroxy-3-methyl-7-phenyl-1,8-naphthyridin-2(l//)-one 4-Hydroxy-5-methyl-7-phenyl-1,8-naphthyridin-2(l//)-one 4-Hydroxy-7-methyl-3-phenyl-1,8-naphthyridin-2(l//)-one 4-Hydroxy-1,8-naphthyridin-2( lZ7)-one 4-Hydroxy-3-nitro-l,8-naphthyridin-2(l//)-one 4-Hydroxy-3-nitro-1 -phenyl-1,8-naphthyridin-2(l//)-one... 

Catalytic reduction of 3-nitro-7-phenyl-l,8-naphthyridin-2(lH)-one (136) with palladium on carbon in 2-ethoxyethanol gave the l,2-di(l,8-... 

Phenyl-2//-pyrido 2,3-<7 [l,3]oxazine-2,4(l//)-dione (64) with diethyl malo-nate gave ethyl 4-hydroxy-2-oxo-l-phenyl-l,2-dihydro-l,8-naphthyridine-3-carboxylate (65) (reactants, NaH, 150°C 85%) 453,407 the same substrate (64) with ethyl nitroacetate gave 4-hydroxy-3-nitro-l-phenyl-1,8-naphthyr-idin-2(lfl)-one (66) (NaH/MeCONMe2, 100°C 77%).1191... 

Anilino-5-methyl-l,8-naphthyridin-2-amine 2-Anilino-7-methyl-5-phenyl-l,8-naphthyridine 2-Anilino-1,8-naphthyridine 2-Anilino-3-nitro-1,8-naphthyridine 2-Azido-4-chloro-5,7-dimethyl-3-phenyl-l, 8-naphthyridine... 

Methoxy-1,8-naphthyridine-2,7-dicarbaldehyde 7-Methoxy-1,8-naphthyridin-2(l//)-one 2-Methoxy-3-nitro-1,8-naphthyridine 2-Methoxy-3-nitro-6-phenyl-7-piperidino-... 

It was reported that the Niementowski synthesis of 4-hydroxy-3-nitro-7-phenyl-l,8-naphthyridin-2(lH)-one (25) from ethyl 2-amino-6-phenylni-cotinate (23) and ethyl nitroacetate (24) in the presence of sodium was unsuccessful, producing only traces of (25), while condensation of ethyl 2-amino-6-phenylnicotinate (23) with the less reactive ethyl acetate resulted in the formation of 4-hydroxy-7-phenyl-l,8-naphthyridin-2(lH)-one in good yield [66JCS(C)315], It seems that the more reactive nitroacetate tends to precipitate rapidly from the reaction mixture as its sodio derivative, which explains the low yield of (25). 

Hydroxy-1,6-naphthyridin-5(6Z/)-one 4-Hydroxy-3-nitro-1,6-naphthyridin-2(l//)-one 6-Hydroxy-7-phenyl-1,6-naphthyridin-5(6//)-one 4-Hydroxy-1,6,7-trimethyl-1,6-naphthyridine-2,5(1//,6//)-dione... 

A similar reaction is found in the formation of 5-amino-l-cyano-2,4-dimethyl-3.106-dihydrobenzo[c][2,7]naphthyridine by reduction of 3,5-dicyano-2,6-dimethyl-4-(2-nitro-phenyl)-l,4-dihydropyridine [87] and tetrahydroquino[2,l-c]benzodiazepines from 2-cyano-l-(2-nitrobenzyl)-l,2,3,4-tetrahydroquinoline [88], When the hydroxylamino group has a choice between a nitrile or an ester group, as in 3-ethoxycarbonyl-5-cyano-2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine, it condenses with the nitrile in acidic solution and with the ester in basic media [89]. 

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