Spatial Configuration of Derivatives of 5,5a,6,7-Tetrahydropyrido[1,2-a]benzimidazole and 6,7-Dihydro-5aH-pyrido[1,2-b]benzoxazole

The spatial configurations of 7,9-diphenyl-5a,6-tetramethylene-5,5a,6,7-tetrahydropyrido[1,2-a]benzimidazole and 7,9-diphenyl-5a,6-tetramethylene-2,5a,6,7-tetrahydropyrido[1,2-a]benzimidazol-2-one have been established by X-ray crystallography. Analogous configurations are proposed for a series of other derivatives of 5,5a,6,7-tetrahydropyrido[1,2-a]benzimidazoles and some derivatives of 6,7-dihydro-5aH-pyrido[1,2-b]benzoxazoles on the basis of ¹H NMR spectroscopic data and the results of quantum chemical calculations using the MNDO, AM1, and PM3 methods.     

Formylation of Furyl-substituted Imidazo[1,2-a]pyridine, Imidazo[1,2-a]pyrimidine and Imidazo[2,1-b]thiazole

Vilsmeier formylation of 2-(2-furyl)-substituted imidazo[1,2-a]pyridine and imidazo[1,2-a]pyrimidine, and also 6-(2-furyl)imidazo[2,1-b]thiazole with 1 mole of reagent occurs at the free position of the imidazole ring, while with an excess of the reagent it also occurs at the position 5 of the furyl group.     

Condensed Isoquinolines. 17. Enamine Properties of Benzimidazo[1,2-b]isoquinolin-11(5H)-one in Alkylation Reactions

The alkylation of benzimidazo[1,2-b]isoquinolin-11(5H)-one has been studied. This occurs at N₍₅₎ or C₍₆₎ depending on the type of alkylating agent and the reaction conditions. It was shown that C₍₆₎ alkylation is effected in reactions with reactive alkyl halides. A repeat alkylation occurs preferentially at the same position. Interaction with o-xylylidene dibromide leads to spiro[benzimidazo[1,2-b]-isoquinolin-6,2'-indan]-11-one and 1,6-dihydro-11H-6a,11b-diazobenzo[b]benzo[5,6]cyclohepta[1,2,3-l,m]fluoren-11-one, which are derivatives of new heterocyclic systems.     

4a-Alkyl Derivatives of 5-Oxo-4H-4a,5-dihydroindeno[1,2-b]pyridine

High selectivity has been discovered for the C-alkylation of ambident anions of 5-oxo-1H-4,5-dihydroindeno[1,2-b]pyridines with ethyl bromoacetate, allyl, propargyl, and phenacyl bromides, which leads to the formation of the corresponding 4a-substituted 5-oxo-4H-4a,5-dihydroindeno[1,2-b]pyridines in high yield.     

Carbocyclic and nitrogen-containing fused CH-acids with an annelated indenyl fragment. Thermogravimetric and X-ray structural analysis of 6H-indeno[1,2-b]quinoline

Based on thermogravimetric characteristics first obtained for the model 6H-indeno [1,2-b]quinoline, the scheme of thermal conversions of this compound in the temperature range 20–700 °C has been proposed, and the limit of its thermal stability (300 °C) has been determined. This temperature is recommended as the optimum for synthesizing fused benzoaza(diaza)fluorenes. Based on the results of X-ray structural analysis, the molecules of the studied indenoquinoline form centrosymmetric pairs, which are arranged in (110) layers. The molecules are orientationally disordered. The observed self-association of these molecules is similar to the - association of fused heterocyclic systems with-excessive and ****- deficient fragments. It has been suggested that interferon-inducing and antitumor compounds with an annelated indenyl fragment have a common mechanism of action according to the intercalation model of stacking structures.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 703–709, April, 1995.     

Synthesis of hexahydroazonino[5,6-b]indoles from hexahydroazepino[4,3-b]-and-[3,4-b]indoles and activated alkynes

A reaction of substituted hexahydroazepino[4,3-b]-and-[3,4-b]indoles with activated alkynes was studied. A one-step method for the synthesis of isomeric hexahydroazonino[5,6-b]indoles different by positions of the double bond in the azonine ring was developed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2244–2250, November, 2007.     

Synthesis of 12-aryl-1-oxo-1,2,3,4,5,12-hexahydroindolo-[2,1-b]quinazoline-6-carbonitriles by recyclization of 11-aryl-1-oxo-2,3,4,5,10b,11-hexahydro-1H-indolo[2,3-b]quinoline-10b-carbonitriles

A general and convenient method for the synthesis of 12-aryl-1-oxo-1,2,3,4,5,12-hexahydroindolo[2,1-b]quinazoline-6-carbonitriles was proposed. The method is based on the recyclization of 11-aryl-1-oxo-2,3,4,5,10b,11-hexahydro-1H-indolo[2,3-b]quinoline-10b-carbonitriles. The structure of 12-(3-methoxyphenyl)-8-methyl-1-oxo-1,2,3,4,5,12-hexahydroindolo[2,1-b]quinazoline-6-carbonitrile was studied by X-ray diffraction analysis.     

Synthesis of 4b,5,10a,11-tetrahydroindeno[1,2-b]quinolin-10-ones from Baylis-Hillman adducts

We developed an efficient synthetic method for indenoquinoline skeletons from Baylis-Hillman adducts. 4b,5,10a,11-Tetrahydroindeno[1,2-b]quinolin-10-ones and 7H-indeno[2,1-c]quinolines were prepared from Baylis-Hillman adducts in polyphosphoric acid.     

Condensed isoquinolines 28*. Synthesis and properties of 10a,15b-diazadibenzo[a,e]-pleiaden-11-ones

The reaction of 7,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-ones with o-xylidene dibromide leads to 11-oxo-4bH,5H,10H,11H,16H-10a-aza-15b-azoniadibenzo[a,e]pleiadene bromides, which are converted to 11-oxo-10H,11H,16H-10a-aza-15b-azoniadibenzo[a,e]pleiadene salts upon oxidation using nitrobenzene. The reaction of these salts with benzylamine leads to 6-{2-[(benzylimino)methyl]phenyl}-7,12-dihydroisoquino[3,2-b][2]benzazepin-14(6H)-ones, which recyclize to 11-oxo-5H,10H,11H-10a-aza-15b-azoniadibenzo[a,e]pleiadene perchlorates upon the action of perchloric acid. The reactions of the 10a,15b-diazadibenzo[a,e]pleiadene salts obtained with NaBH₄ were studied and the structures of the reduction products were determined by spectral methods. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 280–292, February, 2008.     

微波辐射下一锅法合成2-氨基-6-溴-4-芳基-5H-茚并[1,2-b]吡啶-3-腈衍生物

以芳香醛、4-溴茚酮、丙二腈和醋酸铵为原料,分别用微波辐射和传统加热法,一步法合成7种未见文献报道的2-氨基-6-溴基-4-芳基-5H-茚并[1,2-b]吡啶-3-腈衍生物.对比两种方法,在常压下微波具有反应时间短、产率较高等特点.所有化合物均经IR,1HNMR和元素分析确定.     

Condensed Isoquinolines. 16. Enamine Properties of Benzo[4,5]imidazo[1,2-b]isoquinolin-11(5H)-one in Terms of Its Acylation Reactions

A study has shown that the acylation of benzo[4,5]imidazol[1,2-b]isoquinolin-11(5H)-one occurs at N₍₅₎ or at C₍₆₎ depending on the nature of the acylating reagent and the reaction conditions. It was found that principally C-acylation takes place in the absence of base. The reaction with -halo-substituted carboxylic acid chlorides leads to the formation of C-acylated products which are converted to derivatives of the novel heterocyclic system 7H-2a,6b-diazabenzo[b]cyclopenta[l,m]fluorene-1,7(2H)-dione in the presence of base.     

Bromination of Substituted 5H-Imidazo[1,2-b]-1,2,4-triazepin-4-ones and -thiones

The reactions of substituted 5H-imidazo[1,2-b]-1,2,4-triazepin-4-ones and -thiones with bromine and N-bromosuccinimide have been studied. Derivatives of 3- and 8-bromo-, 3,8-dibromoimidazo[1,2-b]-1,2,4-triazepine and 5H-2-bromomethyl-3-methyl-7,8-diphenylimidazo[1,2-b]-1,2,4-triazepin-4-one are formed, depending on the degree of substitution, the nature of the brominating agent, and the reaction conditions.     

Synthesis of derivatives of a new heterocyclic system pyrazolo[3,4-b]pyrido[1′,2′: 1,2]imidazo[4,5-d]pyridine

1-[4-Aminoarylpyrazolo[3,4-b]pyridin-5-yl]pyridinium chlorides undergo cyclization under reflux in tert-butanol in the presence of an excess of potassium tert-butoxide to form tetracyclic derivatives of pyrazolo[3,4-b]pyrido[1′,2′:1,2]imidazo[4,5-d]pyridine. The reaction scheme of the processes is proposed. The structures of the reaction products were confirmed by physicochemical methods. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 710–714, April, 2006.