Synthesis and characterization of [1,2,5]chalcogenazolo[3,4-f]benzo[1,2,3]triazole and [1,2,3]triazolo[3,4-g]quinoxaline derivatives

The synthesis and characterization is reported of low bandgap [1,2,5]chalcogenazolo[3,4-f]benzo[1,2,3]triazole and [1,2,3]triazolo[3,4-g]quinoxaline derivatives that display higher solubility and stability then their thiadiazole counterparts, [1,2,5]chalcogenazolo[3,4-f]benzo[2,1,3]thiadiazole and [1,2,5]thiadiazolo[3,4-g]quinoxaline, respectively.     

Synthesis of thieno[2,3-d]thia[1]pyrano[4,3-b]pyrrole derivatives

It is shown that 2-methyl-3-carbethoxy-4H,8H,5,6-dihydrothieno[2,3-d]thia[1]pyrano [4,3-b]pyrrole and 8-methyl-9-carbethoxy-10H,5,6-dihydrothieno[2,3-d]thia[1]chromeno[4,3-b]pyrrole and their S,S-dioxides, respectively, are obtained in the reaction of 2-methyl-3-carbethoxy-4-thienylhydrazine with tetrahydro-4-thiopyrone, tetrahydro-4-thiopyrone S, S-dioxide, 4-thiochromanone, and 4-thiochromanone S,S-dioxide in the presence of an acid catalyst.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 195–196, February, 1979.     

Synthesis of [1,3]benzoxazino[2,3-k-and [2,4]benzodiazepino[3,2-k]-carbazole derivatives

Alkylation of 4a-methyl-, 4a,6-dimethyl- and 6-bromo-4a-methyl-2,3,4,4a-tetrahydro-1H-carbazoles using 2-chloromethyl-4-nitrophenol gives [1,3]benzoxazino[2,3-k]carbazoles. Derivatives of [2,4]benzodiazepino[3,2-k]carbazole have been synthesized by alkylation of the indicated carbazolenines using 2-bromomethylbenzonitrile followed by hydrolysis of the nitrile group of the 9-(2-cyanobenzyl)-carbazolium salts obtained to amide.Kaunas Technological University, Kaunas, LT-3028, Lithuania Translated from Khimiya Geterotsiklichenskikh Soedinenii, No. 6, pp. 818–821, June, 1999.     

Synthesis of benzo[g]quinoline derivatives

In the condensation of 1, 2, 3, 4-tetrahydro-4-oxobenzo[g]quinollne with ammonia, which leads to the formation of 4-aminobenzo[g]quinoline, the by-products are benzo[g]quinoline (V) and 1, 2, 3, 4-tetrahydrobenzo]quinoline (VI), which are also obtained from 1, 2, 3, 4-tetrahydro-4hydroxybenzo[g]quinoline by its dehydration and the subsequent disproportionation of the dihydrobenzo[g]quinoline formed.For communication II, see [1].     

Synthesis of [1,2,4]triazoloquinazoline and [1,2,4]-triazolo-1,4-benzodiazepine derivatives

Some [1,2,4]triazolo[1,5-c]quinazolin-5(6H)-ones 7 , the corresponding isomers [1,2,4]triazolo[4,3-c]quinazo-lin-5(6H)-ones and the 5-amino derivatives 8, 9 and 11 have been synthesized starting from the acylamidrazones 5 . The preparation of 5H-[1,2,4]triazolo[1,5-d]-1,4-benzodiazepin-6(7H)-ones 15 and of 5-cyclicaminomethyl-[1,2,4]triazolo[1,5-c]quinazolines 16 and 17 is also reported.     

Synthesis of tetrahydrodibenzodipyrazolo-[1,2,5,8,9,12]- and-[1,2,5,6,9,12]-hexaazacyclotetradecine derivatives

The reaction of nickel(II) nitrate with 4-(2-bromo-4-methyl-1-phenylazo)-3-amino-5-methy1-2-alkylpyrazoles by refluxing in dimethylformamide in the presence of K₂CO₃ followed by purification with a column filled with Al₂O₃ gave [1,10,11,20-tetrahydro-1, 11-dipropyl-3,8,13,18-tetramethyIdibenzo[c,j]dipyrazolo[3,4-f:3,4-m] [1,2,5,8,9,12]hexaazacyclotetradecinato(2-)-4,10,14,20]nickel and [1,14,15,20tetrahydro-1, 14-dipropyl-3,7,12,17-tetramethyldibenzo[c,j]dipyrazolo[4,3-g:3,4-m] [1,2,5,6,9,12]hexaazacyclotetradecinato(2-)-5,10,15,20]nickel, which were characterized by the results of elementary analysis and the IR, UV, PMR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1097–1103, August, 1978.     

Synthesis of [1,5]benzothiazepine derivatives

Various derivatives of 2,3-dihydro[1,5]benzothiazepin-4(5H)-ones were synthesized. Alternative route for the synthesis of 5-dimethylaminoethyl-2,3-dihydro[1,5]benzothiazepin-4(5H)-ones and 4-dimethylaminopro-poxy-(2H,5H)-[1,5]benzothiazepines are described.     

Synthesis of benzo[g]quinoline derivatives

The synthesis of 4-aminobenzo[g]quinoline has been effected by the following three methods: 1) replacement of the halogen in 4-chlorobenzo[g]quinoline by an amino group; 2) dehydrogenation of the oxime of 1,2,3,4-tetrahydro-4-oxobenzo[g]quinoline; 3) direct condensation of 1,2,3,4-tetrahydro-4-oxobenzo[g]quinoline with ammonia.     

Synthesis of 3-amino derivatives of benzo[b]furo[2,3-c]pyridines

The reaction of 1,7-dimethyl-3(2H)-benzo[b]furo[2,3-c]pyridone with phosphoric acid amides gave 1,7-dimethyl-3-dimethylamino (morpholino)benzo[b]furo[2,3-c]pyridines. A method for the synthesis of 3-amino derivatives of 4-nitrobenzo[b]furo[2,3-c]pyridines, which consists in heating 1,7-dimethyl-4-nitro-3(2H)-benzo[b]furo[2,3-c]pyridone with hexamethyldisilazane and secondary or primary amines in pyridine, was developed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1552–1555, November, 1991.     

[1]Benzothienoindolizidinones and [1]benzothienoquinolizidinones: Synthesis and schmidt rearrangement into [1,3]diazepines derivatives

[1]Benzothienoindolizidinones 5ac,ae,bc and [1]Benzothienoquinolizidinone 5ad were synthesized from 2(3)-bromethyl[1]benzothiophene and methyl prolinate, methyl oxoprolinate and ethyl pipecolinate. The Schmidt rearrangement of ketones 5 led exclusively to the [1,3]diazepines derivatives 6 .     

Mass spectrometric investigation of some [1]benzopyrano[3,4-c]pyrazole and [1]benzopyrano[4,3-d]isoxazole derivatives

The fragmentation behaviour of some [1]benzopyrano[3,4-c]pyrazole and [1]benzopyrano[4,3-d]isoxazole derivatives under electron impact is described.     

Synthesis of [1,3]dithiole and spiro[1,3]dithiole thiopyran derivatives of the [1,2]dithiolo[1,4]thiazine ring system

We report the synthesis of some new polysulfur-nitrogen heterocycles by cycloaddition reactions to readily available tricyclic condensed 1,2-dithiole-3-thiones. Thus, treatment of bis[1,2]dithiolopyrrole ketothione 1 with diacyl acetylenes gave the bis-aducts 2a-d. On the other hand, cycloaddition of bis[1,2]dithiolo[1,4]thiazine ketothione 3 with 1 equiv of acyl or diacyl acetylenes gave [1,3]dithiolylidenyl[1,2]dithiolo[1,4]thiazines 4a-f in fair to high yields. Catalysis by scandium triflate was used in the reactions that implied the less reactive dipolarophiles. Treatment of 3 with 2 equiv of DBA gave the bis-aduct 5a, and reaction of 4c with DMAD gave the mixed bis-adduct 5b. Cyclic voltammetry of selected examples showed irreversible processes that were influenced by the electrochemical activity of peripheral groups bonded to the heterocyclic system.     

Benzo[b]thiophene derivatives. VIII. Benzo[b]thiophene-3-earboxaldehyde and derivatives

A procedure for the preparation of benzo[b]thiophene-3-carboxaldehyde from 3-methyl-benzo[b]thiophene is reported. This aldehyde behaves as a typical reactive aromatic aldehyde with respect to oxidation, reduction, the mixed Cannizzaro reaction, reductive amination and acyloin and other condensation reactions.     

Synthesis of 1H-[1,2]diazepino[4,5-b]indole derivatives

A synthesis of four 1H-[1,2]diazepino[4,5-b]indole derivatives and some preliminary information about their biological activity are presented. The starting materials were 2-ethoxycarbonylindoles and 2-ethoxy-carbonyl-3-formylindoles, la, b and 2a, b, respectively. 2-Ethoxycarbonyls la, b reacted with 1-dimethylamino-2-nitroethylene and -2-ethoxycarbonyl-3-formylindoles 2a, b in the presence of nitroalkanes (nitromethane or nitroethane) giving 3-(2-nitrovinyl)indoles 3a, b. Reduction of 3a, b yielded β-(2-oxoalkyl)indoles 4. On reaction with an excess of hydrazine hydrate, compounds 4 gave satisfactory yields of 5-oxo-1H-[1,2]diazepino[4,5-b]indoles 5.     

Destructive hydrazinolysis of [1,2,4]triazolo[3,4-b]-[1,3,4] thiadiazole derivatives

The hydrazinolysis of 2-mercapto[1,2,4]triazolino[3,4-b][1,3,4]triadiazole-5-thione and its S-methyl and disulfonyl derivatives leads to opening of the thiadiazole ring during attack by the nucleophile on the bridge carbon atom. A study of the structures of the reaction products and calculations by the Hückel MO and Pariser-Parr-Pople (PPP) method makes it possible to draw a conclusion regarding the mechanism of the hydrazinolysis.     

Syntheses of an isoannelated annulene,a bisdehydro[14]annuleno[c]furan and bisdehydro[14]annulene derivatives

A bisdehydro[14]annuleno[c]furan, an isoannelated diatropic annulene, has been synthesized. Cyclic glycol, a precursor of the annuleno[c]furan, could be converted into bisdehydro[14]annulene derivatives under mild acidic conditions.     

Benzo[b] thiophene derivatives XVII. Electrophilic substitution of 4-hydroxybenzo[b] thiophene derivatives

A variety of eleclrophilic substitution reactions have been carried out on 4-methoxybenzo[b]-thiophene (IIIa) and 4-benzoyloxybenzo[b ] thiophene (IVa). Substitution occurs in the 7-position of IIIa and, with the exception of bromination, in the 7-position of IVa. Bromination of IVa occurs in the 3-position. Bromination of 4-hydroxybenzo[b] thiophene (IIa) occurs in the 5-position. The nmr spectra of eleven disubstituted benzo[b] thiophenes have been tabulated.     

Investigation of imidazo[1,2-a]benzimidazole derivatives

Esters of 1-alkyl- and 1-aralkyl-2-iminobenzimidazoline-3-acetic acids are converted to esters of 2,9-dimethylimidazo[1,2,-a]benzimidazole-3-carboxylic acid on heating with acetic anhydride. The brief action of acetic anhydride on the free iminobenzimidazolineacetic acids gives 2-oxo-2,3-dihydroimidazo[1,2-a]benzimidazoles, which are converted to 2,9-substituted 3-acetylimidazo[1,2-a]benzimidazoles on prolonged heating with acetic anhydride.See [1] for communication V.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 111–114, January, 1973.     

Synthesis of benzo[g]quinoline derivatives

A method for the synthesis of 3-substituted benzo[g]quinolin-4-ones by the condensation of 1,2,3,4-tetrahydrobenzo[g]quinolin-4-one with aromatic aldehydes in an alkaline medium has been developed. It has been found that the first stage of the reaction is the formation of the corresponding benzylidene derivative, which then isomerizes into the more stable benzyl derivative. The structure of the 3-substituted benzo[g]quinolin-4-ones obtained, as existing in the tautomeric oxo form, is confirmed by their IR and UV spectra.For Communication VI, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinii, Vol. 6, No. 6, pp. 798–801, June, 1970.     

Synthesis of benzo[g]quinoline derivatives

The electronic spectra of linear benzo[g]quinoline, its 4-substituted derivatives, and some hydrogenated derivatives are examined and discussed.See [1] for communication IX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 662–665, May, 1972.