Spectral characteristics of C-methylflavones

A study has been made of natural C-methylflavones and their dealkylated analogues: 5-hydroxy-4,7-dimethoxy-7-methylflavone (noreucalyptin); 4,5,7-trihydroxy-6-methylflavone; 5-hydroxy-4,7-dimethoxy-6,8-dimethylflavone (eucalyptin); 4,5-dihydroxy-7-methoxy-6,8-dimethylflavone (sideroxylin); 4,5,7-trihydroxy-6,8-dimethylflavone; 4,5,6-trihydroxy-3-methoxy-8-methylflavone (silpin) and 3,4,5,6-tetrahydroxy-8-methylflavone.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 306–309, May–June, 1984.     

Darstellung von 2′,3′-Dideoxy-2′-hydroxymethyl-nucleosiden

Zusammenfassung Die Synthese von geschützten 2,3-Dideoxy-2-hydroxymethyl-nucleosiden wird beschrieben. Die durch ein Mehrstufenverfahren aus Isopropylidenglycerol erhaltenen Nucleoside können als Bausteine zur Darstellung von Oligonucleotiden verwendet werden, deren 2- und 5-Positionen über eine Etherbrücke verbunden sind.

---

Synthesis of 2,3-dideoxy-2-hydroxymethyl nucleosides

Summary The synthesis of protected 2,3-dideoxy-2-hydroxymethyl nucleosides is presented. The nucleosides, obtained in a multi-step procedure starting from isopropylideneglycerol, may be used as building blocks for the synthesis of 2,5-ether linked oligonucleotides.

     

Nitration,amination, and halogenation of Di-O-methylphloracetophenone

Chlorination of the title compound gave 5- and 3-chloro-2-hydroxy-4,6-dimethoxyacetophenone. The nitration of its acetate, followed successively by reduction, diazotization, and reaction with cuprous chloride, gave the 3-substituted series, 2-acetoxy-4,6-dimethoxy-3-nitroacetophenone, 3-amino-2-hydroxy-4,6-dimethoxyacetophenone, and 3-chloro-2-hydroxy-4,6-methoxyacetophenone, respectively. The orientation of substituents in the products was proved. The amino and chloro members of the isomeric 5-substituted series were availablevia 2-hydroxy-4,6-dimethoxy-5-phenylazoacetophenone, the product of the reaction of the title compound with benzenediazonium chloride.

---

Nitrierung, Aminierung und Halogenierung von Di-O-methylphloracetophenon

Zusammenfassung Chlorierung der Titelverbindung gab 5- und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Nitrierung des Acetats, gefolgt von Reduktion, Diazotierung und Reaktion mit CuCl ergab die 3-substituierte Reihe: 2-Acetoxy-4,6-dimethoxy-3-nitroacetophenon, 3-Amino-2-hydroxy-4,6-dimethoxyacetophenon und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Orientierung der Substituenten wird diskutiert. Die Amino- und Chlorderivate der isomeren 5-substituierten Reihe sind über 2-Hydroxy-4,6-dimethoxy-5-phenylacetophenon zugängig, dem Produkt der Reaktion der Titelverbindung mit Phenyldiazoniumchlorid.

     

Furazane disulfilimines

The reaction of 3,4-diaminofurazane and 4,4-diamino-3,3-difurazanyl with dimethyl sulfide ditriflate provided the first syntheses for 3,4-bis(dimethylsulfilimino)furazane and 4,4-bis(dimethylsulfilimino)-3,3-difurazanyl.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1922–1923, August, 1992.     

Reaction of 2-methyl-4,5-dihydrofuran with hydrogen chloride

Reaction of 2-methyl-4,5-dihydrofuran with HCl at 0°C yields 5-chloro-2-pentanone (13%) and 1-(2-methyltetrahydrofuryl-2)-5-chloro-2-pentanone (27%) and at 200° 5-chloro-2-pentanone exclusively.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. I. M. Gubkin State Petroleum and Gas Academy, 117917 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2188–2191, September, 1992.     

Intramolecular cyclization of N-phthalyl-β-aryl-β-alanine phenylhydrazide

The reaction of N-phthalyl--aryl--alanine N-methyl-N-phenylhydrazides with phosphorus oxychloride (at80 °C) is accompanied by further transformations of the initially formed 2-aminoindole derivatives and leads to isoindolo[1,22,3]-pyrimido[5,6-b]indole derivatives. Intermediate 2-aminoindoles were isolated at lower reaction temperatures. The hydrolysis of the isoindolo[1,22,3]pyrimido [5, 6-b]indole derivatives was studied. The structures of the compounds obtained were established on the basis of the PMR, IR, and UV spectra and the results of elementary analysis.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 926–929, July, 1982.     

Kinetics of the alkaline hydrolysis of flavonoid glycosides

Summary 1. In a study of the kinetics of the alkaline hydrolysis of flavone glycosides it has been found that derivatives of 3,3,4,5,7-pentahydroxyflavone hydrolyze faster than derivatives of 3,4,5,7-tetrahydroxyflavone and of 3,4,5,7-tetrahydroxy-3-methoxyflavone.2. In the hydrolysis of diglycosides of 3,3,4,5,7-pentahydroxyflavones the maximum amount of intermediate product is formed after 2 min (3,4,5,7-tetrahydroxyflavone glycoside), and in the case of 3,4,5,7-tetrahydroxy-3-methoxyflavone glycosides after 120–150 min.I. V. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 646–649, September–October, 1977.     

N-acetylindoxyl in the synthesis of new condensed heterocycles

Derivatives of a new heterocyclic system thieno[2,35,6]pyrimido[3,4-a]indole, were obtained by the reaction of substituted N,O-diacetylindoxyls with excess N-(2-methyl-3-ethoxycarbonyl-4-thienyl)hydrazine. The reaction of N-acetylindoxyl and 4-hydrazinouracil forms 12-amino-1,3-dioxo-2,4,6-trimethylpyrimido[5,45,6]pyrimido[3,4-a]indole.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1343–1345, October, 1987.     

Transformed steroids. 160. Reaction of 20,20-dimethoxy-16α,17α-epoxypregn-5-ene-3β, 21-diol-20-one with pyridine thiocyanate and carbethoxyhydrazine

Conclusion The reaction of 20,20-dimethoxy-16,17-epoxypregn-5-ene-3,21-diol-20-one with pyridine thiocyanate in the presence of carbethoxyhydrazine proceeds by two competing paths: cisopening of the oxide ring by a -SCN ion at the C¹⁷ atom, and substitution of one of the methoxyl groups by -NCS ion. As a result 2,20-dicarbethoxyhydrazones of pregn-5-ene-3,21-diol-20-one-[17,16-d]-1,3-oxathiolan-2-one and 20-methoxy-16,17-epoxypregn-5-ene-3-ol-[20,21-d]-1,3-oxazolidine-2-thione are formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 911–914, April, 1987.     

Pyrimidines. 70. Relative reactivities of the chlorine atoms of 2,2′,4-trichloro-4′,5-dipyrimidinyl in its reaction with piperidine

2,2,4-Trichloro-6-phenyl-4,5-dipyrimidinyl, for which nucleophilic substitution with piperdine under various conditions was studied, was obtained from 2,2,4-trioxo-6-phenyl-1, 1,2,2,3,4-hexahydro-4,5-dipyrimidinyl. It is shown that there is an appreciable difference in the rates of substitution of the first, second, and third chlorine atoms, and this made it possible to obtain reaction products that contain one, two, and three piperidino groups. The chlorine atom in the 4 position is replaced initially, after which the chlorine atom in the 2 position undergoes substitution. The structures of the compounds were proved by chemical transformations and analysis of the PMR spectra.See [1] for communication 69.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–826, June, 1979.