L. M. Potikha

Preparation of isoindolo[2,1-a]quinoxalines based on N-(2-aminophenyl)isoindole derivatives

A new method is proposed for the preparation of N-(2-aminophenyl)isoindoles by the reaction of o-(bromomethyl)benzophenones with 1,2-phenylenediamines. The reaction of N-(2-aminophenyl)isoindoles with Ac2O leads to 1,N-diacetyl- or 1,N,N-triacetyl derivatives, whereas heating with formic acid or diethyl oxalate leads to cyclization with the formation of 11-arylisoindolo[2,1-a]quinoxaline derivatives. Salt formation in the 11-arylisoindolo[2,1-a]quin-oxaline series was studied.

Condensed isoquinolines. Part 6. Synthesis of 5-aryl-7,12-dihydroisoquino[2,3-a]quinazolinium salts

Abstract2-(o-Aroyl)phenyl-1, 4-dihydroisoquinolin-3(2H)-imine hydrobromides have been synthesized by the reaction of o-bromomethylphenylacetonitrile with o-aminobenzophenones. The products were cyclized into 5-aryl-7,12-dihydroisoquino[2,3-a]quinazolinium perhclorates.

NEW ACRIDIZINIUM SALTS DERIVED FROM (2-(BROMOMETHYL)PHENYL)CARBONYL COMPOUNDS

A new method is proposed for the preparation of 1-hydroxypyrido[1,2-b]isoquinolinium bromides by intramolecular aromatic electrophilic substitution in 3-hydroxy-1-(2-formylbenzyl)pyridinium, 3-hydroxy- and 3-amino-1-[2-(4-chlorobenzoyl)benzyl]pyridinium bromides. The alkylation of pyridine and some of its derivatives by 2-(bromomethyl)benzaldehyde, 2-(bromomethyl)benzophenone derivatives, and methyl 2-(bromomethyl)benzoate was studied.

Condensed isoquinolines 23. Reaction of o-bromomethylphenyl-acetonitrile with anthranilic acids: Synthesis of 6H, 12H,17H-dibenzo[3,4:6,7][1,8]-naphthyridino[1,8-ab]quinazoline-6,17-diones

The direction of the reaction of anthranilic acids with o-bromomethylphenylacetonitrile upon fusion depends on the temperature and nature of the substituent in the anthranilic acid. The reaction may lead to three types of products: Derivatives of 7,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-ones below 150°C and to 6,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-one or derivatives of 6H,12H,17H-dibenzo[3,4:6,7][1,8]naphthyridino[1,8-ab]quinazoline-6,17-diones above 150°C depending on the nature of the substituent in the anthranilic acid. A study was carried out on the mechanism for the formation of 6H,12H,17H-dibenzo[3,4:6,7][1,8]naphthyridino[1,8-ab]quinazoline-6,17-diones, which permitted the preparation of 6-(4-methylphenyl)-6,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one.

Condensed isoquinolines. 19. Synthesis of 1′-R-spiro[6a,11b-diazabenz[e]aceanthrylene-6(7H),4′ (1′H)-pyridine]-5,7(12H)-diones

During acylation of 7-isonicotinoyl-6,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one or its alkylation followed by treatment with organic bases, spirocyclization occurs with formation of derivatives of a novel heterocyclic system: 1′-acyl-and 1′-alkylspiro[7H,12H-6a,11b-diazabenz[e]aceanthrylene-6(5H),4′(1′ H)-pyridine]-5,7-diones. We have studied the spectral properties of the synthesized spirans. We have shown that 7-nicotinoyl-6,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one does not undergo an analogous reaction of repeated acylation, while treatment of its quaternary salt with bases leads to a complex mixture of unidentified products.

Condensed isoquinolines. 9. Alkylation of 7,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-ones

The alkylation of 7,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one proceeds at N(6) or C(−) depending on the type of alkylating agent and reaction conditions. C(−)-Alkylation occurs in the presence of base. The secondary alkylation of the 7-alkyl derivatives occurs at the same position under these conditions. Depending on the conditions, the reaction with o-xylylene dibromide leads to spiro[5H-isoquino[2,3-a]quinazolin-7(12H).2′-indane]-5-one or 11-oxo-4b,5,10,16-tetrahydro-11H-10a-azonia-15b-azadibenz[a,e]pleiadene bromide, which are derivatives of new heterocyclic systems.

Condensed isoquinoline. 5. Reaction of the 6-methyl-5-oxoisoquino[2,3-a] Quinazolinium cation with certain nucleophiles

It has been shown that nucleophilic reagents react with the 6-methyl-5-oxoisoquino[2,3-a]quinazolinium cation at the C(2) atom. The structure of the reaction product is determined by the type of reagent. On reaction with sodium borohydride and secondary amines, 12H- and 12-dialkylamino-12H-6-methyl-5-oxo-5, 6-dihydroisoquino[2,3-a]quinazolines are formed. In the case of primary amines the reaction is accompanied by fission of the C(12)-N(t3) bond with the formation of 2-[o-(N-alkylformimidoyl)-benzyl]-3-methyl-4-oxoquinazolines.