Condensed derivatives of benzazoles. 1. Synthesis of 6- and 5-substituted benzimidazo[2,1-b]quinazolin-12-ones

6(5)H-Benzimidazo[2,1-b]quinazolin-12-one was obtained in high yield by condensation of benzimidazole-2-sulfonic acid with anthranilic acid. Methods for the introduction of substituents selectively into the 5 and 6 positions of this heterocycle were developed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1673–1677, December, 1987.     

Investigation of the reaction of 1,2,3-trimethyl-2-phenylbenzimidazoline with dehydrogenating reagents by EPR spectroscopy

The reaction of 1,2,3-trimethyl-2-phenylbenzimidazoline with a number of reagents that manifest dehydrogenating properties with respect to benziraidazolines was studied by EPR spectroscopy. These reagents convert 1,2,3-trimethyl-2-phenylbenzimidazoline to a relatively stable cation radical. The mechanism of the dehydrogenation of benzimidazolines is discussed taking into account the established facts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 634–638, May, 1987.     

Organolithium,organosodium, and organomagnesium compounds of azoles (review)

The results of research on the synthesis and transformations of metallated azoles that contain the metal (lithium, sodium, magnesium) in the heterorings and in the C- and N-substitutents are systematized and correlated. The factors that affect the metallation of azoles and data that pertain to the mechanism of these reactions are discussed.Translated from Khimiya Geterotsiklicheskikh Soedineniie, No. 2, pp. 147–162, February, 1988.     

Organosodium compounds of N-substituted benzimidazoles

1-Alkylbenzimidazoles and 1-benzylbenzimidazole react with phenylsodium to form the corresponding 2-sodio derivatives. 5-Bromo-1-ethylbenzimidazole does not react with phenyl- and amylsodium. The metallation of 1-arylbenzimidazoles with phenylsodium is appreciably complicated by side processes. A path for the preparation of 2-sodio-1-arylbenzimidazoles from 1-arylbenzimidazoles and o-anisylsodium is proposed. Some transformations of the organosodium compounds of N-substituted benzimidazoles were studied.     

Condensation of 2-aminobenzimidazoles with o-substituted benzoyl chlorides

Translated from Khimiya Geterotsiklicheksikh Soedinenii, No. 2, pp. 272–273, February, 1989.