Reaction of some pyrylium salts with hydrazine

2,6-Diphenyl- and 2,6-di-tert-butylpyrylium salts react with excess hydrazine to give 1,2-diazeplne derivatives. Under the same conditions, 4-(1-methyl-3-indolyl)flavylium perchlorate forms 3-phenyl-5-(1-methyl-3-lndolyl)pyrazole.Translated from Khimiya Geterotsiklichesikikh Soedinenii, No. 1, pp. 45–48, January, 1973.     

N-pyrylation of hexahydrocarbazole

4-Methoxypyrylium salts react with hexahydrocarbazole to give 4-(9-hexahydrocarbazoly-pyrylium derivatives. The reaction of the latter with ammonia and hydrazine was investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 347–348, March, 1973.     

Reaction of 1-chloromethylisatin with indole

In the condensation of N-chloromethylisatin with indole and 2-methylindole in the presence of triethylamine, instead of the expected N-skatylisatins the products of their subsequent transformations with opening of the five-membered ring of isatin -o-(N-skatylamino)- and o[N-(2-methylskatyl)amino]benzoylcaproic acids —were isolated. In addition to the formation of these -keto acids, under the indicated conditions one observes dimerization of N-chloromethylisatin and N-chloromethyl-5-methylisatin to give 2-(1-isatinylmethyloxy-3H-indolin-3-one and 2-(5-methyl-1-isatinylmethyloxy)-5-methyl-3H-indolin-3-one, respectively, i.e., dimers containing isatin rings in lactam and lactim forms. The structures of the compounds were confirmed by IR, PMR, and mass-spectral data.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 217–220, February, 1977.     

Mass-spectrometric study of physiologically active β-thiosemicarbazones of N-alkylisatins

The molecular ions of isatin (I) and N-methyl- (II) and N-ethylisatin (III) -thiosemicarbazones undergo fragmentation via many pathways with the elimination of NH₃, H₂S, CO, CH₂N₂, CHN₃, CH₂N₂S, CH₂NS, and CHNS particles; this is due to primary localization of the charge on the heteroatoms of the thiosemicarbazone residue. A previously unknown rearrangement, which consists in migration of an HS group to the -carhon atom of the heteroring with subsequent ejection of a CHN₃ fragment. The [M — CO]⁺ ions undergo fragmentation with the elimination of CH₂N₂S; in the case of II and III fragmentation is preceded by detachment of a hydrogen atom (II) or a methyl group (III) from the substituent attached to the ring nitrogen atom. The [M — CO, -H, -CH₂NS]⁺ (II) and [M — CO, -CH₃, -CH₂N₂S]⁺ (III) ions undergo fragmentation with the ejection of HCN in two ways through both the ring nitrogen atom and the thiosemicarbazone residue. Schemes for the principal pathways of fragmentation and rearrangements are presented. The compositions of the ions were confirmed by the high-resolution mass spectra and the mass spectra of the N-deuteroalkyl derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 75–79, January, 1979.     

Mass spectrometric study of isatins II. N-propyl(allyl,propargyl)isatins

The mass spectra of N-propyl- (I), N-allyl- (IV), and N-propargylisatin (VII) and their 5-methyl (II, V, VIII) and 7-methyl (III, VI, and IX) derivatives were recorded. It is shown that a portion of the [M-2CO]⁺ ions in the mass spectra of N-propargylisatins undergo rearrangement to give ions with a quinoline structure. A scheme for the fragmentation of the investigated compounds is presented. The mass spectra of the 5- and 7-methyl derivatives are compared.See [1] for communication I.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 639–641, May, 1977.     

The reaction of oxindoles with β-diketones

With acetylacetone in the presence of hydrogen chloride, oxindole and 1-acetyloxindole form mixtures of approximately equal amounts of 3-isopropylideneoxindole, 2,4-dimethyl-1-oxoniacarbazole chloride, and the hydrochloride of methyl o-aminophenylacetate. In the case of other 1- and 5-substituted oxindoles, the 3-isopropylidene derivatives have been isolated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1271–1272, September, 1973.     

New pyrylium derivatives in the indole series

Nitrogen-unsubstituted 2,3-dihydroindole and its homologs, as well as 1,2,3,4-tetrahydro-- carbolines, react with 2,6-dimethyl-4-methoxypyrylium perchlorates to give N-pyrylated derivatives of indole, which are converted to the corresponding pyridine bases by the action of ammonium salts and form 1-aminopyridinium derivatives with hydrazine hydrate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1531–1533, November, 1972.