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.     

Synthesis of thiadiazole, dithietane, and imine derivatives of the [1,2]dithiolo[1,4]thiazine ring system

We report the synthesis of some new polysulfur-nitrogen heterocyclics by cycloaddition reactions to the thioketo group of readily available tricyclic 1,2-dithiole-3-thiones. Thus treatment of bis[1,2]dithiolo[1,4]thiazine ketothione 1 with diaryl nitrile imines generated from hydrazonoyl chlorides 2a-g gave [1,3,4]thiadiazolylidenyl[1,2]dithiolo[1,4]thiazines 4a-g in high yield. Compounds 4a-f, bearing the same substituents in both aryl groups, were stable but the analogous 4g,h with a p-nitrophenyl group on carbon gave the bis[1,2]dithiolo[1,4]thiazine dione 9, probably by cycloreversion and hydrolysis during chromatography. Treatment of 1, the bis[1,2]dithiolopyrrole ketothione 13, and dithione 12 with ethoxycarbonyl azide 11 gave imines 12 and 15 and bisimine 16, respectively, by an alternative fragmentation of the initial cycloadduct in which the 1,2-dithiole ring is retained. Reaction of 1 with TosMIC gave the imino-1,3-dithietane 17.     

Selective synthesis of bis[1,2]dithiolo[1,4]thiazines from 4-isopropylamino-5-chloro-1,2-dithiole-3-ones

Reaction of 4-isopropylamino-5-chloro-1,2-dithiole-3-ones 3 and S₂Cl₂ in acetonitrile gave selectively 3-oxo-bis[1,2]dithiolo[1,4]thiazine-5-thiones 1 by the addition of triethylamine and bis[1,2]dithiolo[1,4]thiazine-3,5-diones 5 under the action of formic acid. 3,5-Diones 5 were also obtained by intramolecular cyclization of N,N-bis(5-chloro-3-oxo[1,2]dithiol-4-yl)amines 6 with S₂Cl₂ in the presence of Et₃N.     

Heterocycles containing nitrogen and sulfur. Part 49. Synthesis of derivatives of new heterocyclic systems: 1,2-Dioxocyclopenta(hexa)[g]oxazolidino-[3,2-f] pyrimido[4,5-b][1,4]thiazine, 1,2-dioxocyclopenta(hexa)-[g] imidazolidino[3,2-f]pyrimido[4,5-b][1,4]thiazine, and 1,2-oxazino[5,4-g]pyrimidino[4,5-b][1,4]thiazine

The reaction of 4-methoxy-5-amino-6-mercaptopyrimidine with 2-oxo-1-chlorocyclopentyl(hexyl)glyoxalate esters gave derivatives of the previously unknown tetracyclic systems 1,2-dioxocyclopenta (hexa)[g]oxazolidino[3,2-f]pyrimido[4,5-b][1,4]thiazines, which are transformed by ammonium acetate into derivatives of 1,2-dioxocyclopenta(hexa) [g]imidazolidino[3,2-f]pyrimido[4,5-b]-[1,4] thiazines. Derivatives of the new tricyclic 1-oxazino [5,4-g]pyrimido[4,5-b][1,4]thiazine system were obrtained by reaction of 6-carbethoxy-7-acetylpyrimido [4,5-b] [1,4] thiazines with hydroxylamine.     

CHEMICAL BEHAVIOR OF SOME BENZ[b] INDENO[1,2-e] [1,4] THIAZINE DERIVATIVES

Abstract

The study of the chemical behavior of some benz[b] indeno[1,2-e] [1,4] thiazine derivatives was accomplished. Different reactivities were observed for 4b,5-dihydrobenz[b]-indeno[1,2-e] [1,4] thiazine-10α(11H)-ol (3) and 5-ethyl-4b,5-dihydrobenz[b] indeno[1,2-e]-[1,4] thiazine-10α(11H)-ol (5); 3 is reoxidated to benz[b] indeno[1,2-e] [1,4] thiazine-10α(11H)-ol (2), while 5 undergoes transposition and oxidation to spiro[3-ethylbenzo-thiazol-2(3H), 1′-indan-2′-one] (6). Possible pathways for these transformations are discussed.     

Tetracyclic systems: Synthesis of isoindolo[1,2-b]thieno-[2,3(3,2 or 3,4)-e][1,3]thiazocines and Isoindolo[2,1-a]thieno-[2,3(3,2 or 3,4)-f][1,4] and [1,5]diazocines

Cyclization of thioglycolic acids derivatives 3a-d gave isoindolo[1,2-b]thieno[2,3(3,2 or 3,4)-e][1,3]-thiazocines 4a-d . Isoindolo[2,1-a]thieno[2,3(3,2 or 3,4)-f][1,4] or [1,5]diazocines 10b or 11a-c were synthesized from Beckmann or Schmidt rearrangement of the ketones 7a-c .     

Synthesis and properties of some derivatives of 2-thionoindeno [1,2-d]-pyrimidine and indeno [1,2-d] [3,1] thiazine

Derivatives of 2-thiono-5-oxo-2,3,4,5-tetrahydroindeno[1,2-d] pyrimidine and 5-oxo-1,2,4,5-tetrahydroindeno [1,2-d] [3,1] thiazine are formed in the cyclocondensation of 2-arylideneindan-1,3-diones with thiourea and N-monomethylthiourea, while only derivatives of indeno [1,2-d]-pyrimidine are formed in the reaction with N,N-di-methylthiourea. S- and N(₃)-Alkylation occur in the alkylation of 2-thiono-4-pheny1-5-oxo-2,3,4,5-tetrahydroindeno[1,2-d]pyrimidine, while only the N-methyl derivative is formed in the alkylation of 2,5-dioxo-4-phenyl-1,2,4,5-tetrahydroindeno [1,2-d] [3,1]thiazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1136–1141, August, 1988.     

A one-pot synthesis and 1,3-dipolar cycloaddition of [1,2]dithiolo[4,3-b]indole-3(4H)-thiones

Treatment of N-substituted 2-methyl-1H-indoles 1 with S₂Cl₂ and DABCO in chloroform gave the corresponding [1,2]dithiolo[4,3-b]indole-3(4H)-thiones 5 by the addition of triethylamine in high yield. 1,2-Dithiole-3-thiones 5 underwent cycloaddition with one or two DMAD equivalents to afford either 2-(3-thioxo-1,3-dihydro-2H-indol-2-ylidene)-1,3-dithioles 10 or fused 4,5-dihydrothiopyrano[3,2-b]indoles 9.     

Syntheses of optically active tetrahydro-1H-pyrrolo[1,2-a]imidazol-2-ones and hexahydroimidazo[1,2-a]pyridin-2(3H)-ones

The reactions of (2S)-2-amino-2-substituted-N-(4-nitrophenyl)acetamides 16a-c, succindialdehyde (13), and benzotriazole afforded enantiopure (3S,5R,7aR)-5-(1H-1,2,3-benzotriazol-1-yl)-3-substituted-1-(4-nitrophenyl)tetrahydro-1H-pyrrolo[1,2-a]imidazol-2-ones 17a-c, which were converted by sodium borohydride into (3S,7aR)-3-substituted-1-(4-nitrophenyl)tetrahydro-1H-pyrrolo[1,2-a]imidazol-2-ones 18a-c. Chiral (2S)-2-amino-2-substituted-N-(4-methylphenyl)acetamides 12a-d, easily prepared in two steps from N-Boc-alpha-amino acids 10a-d, similarly reacted with glutaraldehyde (20) and benzotriazole to generate 5-benzotriazolyl-3-substituted-hexahydroimidazo[1,2-a]pyridin-2(3H)-ones 21a-d, which were converted by sodium borohydride directly into optically active 3-substituted-hexahydroimidazo[1,2-a]pyridin-2(3H)-ones 22a-d.     

Novel heterocyclic systems based on 8-R-4,5-dihydro-4,4-dimethyl-[1,2]dithiolo[3,4-c]quinoline-1-thiones

Based on the reaction of 8-R-4,5-dihydro-4,4-dimethyl[1,2]dithiolo[3,4-c]quinoline-1-thiones with oxalyl chloride followed by the reactions of 1,3-dipolar cycloaddition and diene synthesis with participation of acetylenedicarboxylic acid dimethyl ester, we have developed approaches to synthesis of novel polycondensed heterocyclic systems: [1,2]dithiolo[3,4-c]pyrrolo[3,2,1-ij]quinoline-4,5-dione, 6-(1,3-dithiol-2-ylidene)-1,2-dioxo-5-thioxo-7H-pyrrolo[3,2,1-ij]quinoline and 4,5-dioxospiro(pyrrolo)-[3,2,1-ij]thiopyrano[2,3-c]quinoline-11,2′-[1,3]dithiole. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 610–615, April, 2006.     

From cyclopentanone oximes to bis[1,2,3]dithiazolo-s-indacenes, cyclopenta[c][1,2]thiazine, pentathiepino-, tetrathiino-, and thienocyclopenta[1,2,3]dithiazoles as a rich source of new materials

[Structure: see text]. The 1,5- and 1,7-s-hydrindacenedione dioximes reacted with S2Cl2 and iBu3N to give the first examples of bis[1,2,3]dithiazolo-s-indacenes; one of them was a near-infrared dye. In contrast, the silylated bicyclo[3.3.0]octan-2,6-dione dioxime reacted with S2Cl2 and Et3N to give a bicyclic 4-cyanoethylcyclopenta[1,2,3]dithiazole or, after addition of Li2S, a tricyclic 4-cyanoethyl-5,6-pentathiepinocyclopenta[1,2,3]dithiazole, also obtained from 2-cyanoethylcyclopentanone oxime, S2Cl2, and Hünig's base. In related reactions, 2-oxocyclopentylpropionate oxime gave the expected cyclopenta[1,2,3]dithiazole, in addition to an unexpected cyclopenta[c][1,2]thiazine that showed a reversible reduction wave in its CV at -0.95 V. Ethyl 2-oxocyclopentanecarboxylate oxime reacted with S2Cl2, Hünig's base, and Li2S to give a 5,6-tetrathiinocyclopenta[1,2,3]dithiazole derivative. Cyclopentathiophen-4-one oximes reacted with S2Cl2 and iBu3N to give thienocyclopenta[1,2,3]dithiazoles that showed UV-vis spectral bands that depended on the positions of the ring fusion.     

Research on imidazo[1,2-a]benzimidazole derivatives.

3-Alkoxycarbonyl-2-arylimidazo[1,2-a]benzimidazoles were synthesized by alkaline cleavage of 3-trichloromethyl ketones of the imidazo[1,2-a]benzimidazole series, which are formed by acylation of this three-ring system with trichloroacetyl chloride. The same compounds were also obtained by esterification of the corresponding 3-carboxylic acid. The haloform reaction with 3-acetyl-2-phenylimidazo[1,2-a]benzimidazole proceeds anomalously and leads to bis(9-methy1-2-phenylimidazo[1,2-a]benzimidazo1-3-yl)-2-buten-1,4-dione, the structure of which was confirmed by independent synthesis.See [1] for communication XV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 522–525, April, 1978.     

Reaction of dichloroketene and sulfenc with N,N-disubstituted 2-aminomethylene-1 -indanones. Synthesis of indeno[ 1,2-b ] pyran and lndeno[2,l-e] -1,2-oxathiin derivatives

The 1,4-cycloaddition of dichloroketene to N,N-disubstituted 2-aminomethylcnc-l-indanones afforded N,N-disubstituted 4-ainino-3,3-dichloro-3,4-dihydro-2-oxoindeno[1,2-b ]pyrans only in the case of full or partial aromatic N-substitution. The diphenylamino adduct gave 3-chloro-4-diphenylamino-2-oxoindeno[ 1,2-b]pyran by dehydrochlorination with DBN. The 1,4-cycloaddition with sulfene occurred only in the case of 2-diethylaininomethylene-1-indanone to give 4-diethylamino-3,4-dihydroindeno[2, 1-e]-1,2-oxathiin 2,2-dioxide, a derivative of a new hetero-cyclic system.     

Cyanine dyes from naphtho [1,2-6]thiazolo[3,2-d][1,4]thiazine

Deeply colored cyanine dyes have been synthesized from the previously unknown 3-methyl-12H-naphtho[1,2-b]thiazolo[3,2-d][1,4]thiazinium salts. It is assumed that the deep color of the new cyanines is connected with the conversion of the nonaromatic 1,4-thiazine ring in the dye molecule into an aromatic thiazine ring with three double bonds in a six-membered ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1282–1284, September, 1973.     

Pyridyl-substituted [1,3]Dithiolo-[4,5-<Emphasis Type="Italic">b</Emphasis>][1,4]dithiine-2-thiones

We have obtained 5-(2-pyridyl)[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione for the first time by cycloaddition of 2-ethynylpyridine to 4,5-dihydro-1,3-dithioltrithione (isotrithionedithiol). We have studied this thione, 5-(2-pyridyl)- and 5-(4-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thiones by mass spectroscopy and also IR, UV, ¹H and ¹³C NMR spectra. We have determined the crystal and molecular structure of 5-(2-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 429–434, March, 2005.     

Diazepines. III. Synthesis of 4H-Pyrrolo[1,2-a] thieno[3,2-f] [1,4] diazepines

The synthesis of 4H-pyrrolo[1,2-a]thieno[3,2-f] [1,4]diazepines ( 8 ) is described. Phthal-imidomethylfurans 1 were treated with bromine-methanol to give the dihydrofurans 2 , which were hydrolyzed and then liydrogenated over Raney nickel or with zinc-acetic acid to afford the 1,4-diketones 5 . Condensation of 2-amino-3-benzoylthiophenes 6 with 5 gave 3-benzoyl-2-pyrrolylthiopenes 7 . The removal of the phthaloyl group from 7 with hydrazine hydrate and ring closure to the diazepine ring yielded the new heterocycles 8 .     

Synthesis of 5,6-dihydro-4H-pyrrolo[1,2-a]thieno[2,3-f][1,4]diazepines

The reduction of 1-[3-(thienyl-2-carbonitrile)]pyrrole, formed by condensation of 3-aminothiophene-2-carbonitrile with 2,5-dimethoxytetrahydrofuran, gave 1-[3-(thienyl-2-aminomethyl)]pyrrole. This compound was found to be a convenient intermediate for the preparation of 4-aryl-5,6-dihydro-4H-pyrrolo[1,2-a]thieno-[2,3-f][1,4]diazepines which was accomplished by two different synthetic routes.     

Synthesis and some reactions of naphth[1,2-d]oxazole-5-sulfonic acids

Naphth[1,2-d]oxazole-5-sulfonic acid ( 1 ) has been prepared by the fusion of 4-amino-3-hydroxynaphthalene-1-sulfonic acid with formamide. Interaction of 1 with a number of arenesulfonyl chlorides, aryloxyacetyl chlorides, 1-naphthyloxyacetyl chloride, and chloroacetyl chloride gave 2-(arylsulfonyl)-, 2-(aryloxyacetyl)-, 2-(1-naphthyloxyacetyl)- and 2-(chloroacetyl)naphth[1,2-d]oxaxole-5-sulfonic acids ( 2, 3, 4 and 5 ), respectively. The corresponding sulfonyl chloride of 2 was condensed with amines giving the expected 2-(arylsulfonyl)-naphth[1,2-d]oxazole-5-sulfonamides ( 6 ). Interaction of 5 with hydrazine gave 2-hydrazinoacetyl and disubstituted hydrazine derivatives 7 and 8 . Condensation of 7 with aromatic aldehydes yielded substituted hydrazonoacetyl derivatives 9 . Two moles of 5 react with one mole of hydroquinone in dry acetone in the presence of anhydrous potassium carbonate and potassium iodide gave 1,4-bis[5-sulfonaphth[1,2-d]oxazol-2-ylcarbonyl-methoxy]benzene ( 10 ).     

Synthesis of cycl[3.2.2]azine and benzo[g]cycl[3.2.2]azine derivatives by use of the [2 + 8] cycloaddition reaction of indolizines and dimethyl acetylenedicarboxylate

The reaction of 1-ethoxycarbonylmethylpyridinium bromides 5a-k with nitro ketene dithioacetal, 1,1-bis-(methylthio)-2-nitroethylene ( 2 ), in the presence of triethylamine in ethanol gave the desired ethyl 2-methyl-thioindolizine-3-carboxylates 3a-k in good yields, along with ethyl 2-methylthio-1-nitroindolizine-3-carboxyl-ates 4a-d . Deesterification of 3 using sodium hydroxide in methanol followed by treatment with polyphosphoric acid gave the corresponding 2-methylthioindolizines 5a-d in good yields. The desulfurization of 5 with Raney-nickel in ethanol occurs smoothly to give the 1,2,3-unsubstituted indolizines 6a-c (a , parent indolizine; b , 8-methylindolzine; c , 6,8-dimethylindolizine). Similarly, pyrrolo[2,1-a]isoquinoline ( 19 ) was also synthesized. These indolizine and pyrrolo[1,2-a]isoquinoline derivatives were allowed to react with dimethyl acetylene to give the corresponding cycl[3.2.2]azine and benzo[g]cycl[3.2.2]azine derivatives in good results.     

Synthesis and autoxidation of new tetracyclic 9H,10H-indolizino[1,2-b]indole-1-ones.

The new tetracyclic 9H,10H-indolizino[1,2-b]indole-1-one derivatives (7a-d, 7ea, 7eb) have been synthesized by modified Fischer indole synthesis from the enol ether of 2,5-dihydroxy-7-methyl-6-cyano-indolizine (3) and arylhydrazines (4a-g). Attempted N-methylation of 7a-d produced a series of autoxidized products including 10-hydroperoxy-1-methoxyindolizino[1,2-b]indole (9a-d) as the major product accompanied with methylperoxides (10a-d and 11a-d) and 2-formyl-3-(pyridine-2-yl)indole (12a, 12c) derivatives as the minor products. A plausible mechanism of the autoxidation is postulated based on the isolation of some intermediates. The reaction is thought to proceed through azaenolate/enamine intermediates following a novel type of autoxidation.