Benzo phenanthridones

Successful cyclizations (albeit in low yields) have been reported in the case of the amides (101)134 and (102),135 although no benzo-phenanthridone was obtained from (103).136 7-Methoxycarbonyl-... 

The oxidation of 5-aminophenanthridone with lead tetraacetate in methylene chloride leads to benzocoumarin and phenanthridone rather than benzo[c]cinnoline (cf. the oxidation of l-amino-3,4,5,6-tetraphenylpyridone349). 

Begley and Grimshaw (94) reported a modified synthesis of nitidine (77) by shortening the steps in Kessar s route (88) by using the A -methylbenza-mide (93) under photochemical conditions. However, they failed to obtain benzo[c]phenanthridone by electrochemical means (94) (Scheme 47). 

In particular, the process has been employed in the construction of benzo[c]phenanthridines and benzo[c]phenanthridones,of 3-benzazepines and 3-benzoxep-ines, and of functionalized 6-alkylated purines. ... 

Isoquinoline-1,3,4-triones are useful intermediates for the synthesis of benzo[c]phenanthridones in about a 30% yield in a three step sequence which utilises... 

The photocyclisation of A-phenyl-3-vinylquinolin-2( )-ones provides a facile route to benzo[k]phenanthridones. Under non-oxidative conditions, the tetrahydro derivative results, but photolysis in the presence of iodine gives the fully aromatic heterocycle. Introduction of a 2-chlorine substituent into the starting material results in the formation of 6-chloro-7,8-dihydrobenzophen-anthridones (K. Veeramani et al.. Synthesis, 1978, 855). 

Photolysis of styrylquinolones (130) affords benzo-[k]phenanthridones whilst the benzylidene lactones (131), from which the styrylquinolones may be prepared, give 6-oxobenzo[k]phenanthridine-7-carbo3 1ates on irradiation in methanol (V. Arisvaran et al,. Synthesis, 1981, 821). 

Benson JM, Royer RE, Galvin JB, et al. 1983. Metabolism of phenanthridone to phenanthridone by rat lung and liver microsomes after induction with benzo(a)pyrene and Aroclor. Toxicol Appl Pharmacol 68(1) 36-42. 

With N-methylbenzamides, the yields of substitution products are lower. > The S j l reaction between substituted o-iodobenzamides and the enolate anion of 2-acetylhomoveratic acid can be used for the synthesis of derivatives of the benzo(c)-phenanthridone and berberine alkaloids. ... 

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