Synthesis of 3,4-di(methylene)tetrahydrothiophene-1,1-dioxide and its use in organic synthesis

A convenient reaction scheme has been developed for obtaining 3,4-di(methylene)tetrahydrothiophene-1,2-dioxide from the readily available 3,4-dimethyl-2,4-dihydrothiophene-1,1-dioxide through 3,4-di(bromomethyl)-2,5-dihydrothiophene-1,1-dioxide. A feasibility study has been made of the use of the butadiene fragment of the heterocycle in a Dieb—Alder reaction with maleic acid derivatives, and the corresponding adducts have been obtained.DeceasedTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 173–175, February, 1992.     

Synthesis and configuration of 4-alkyl-2-methyl-3,4-diphenyl-1,2-thiazetidine 1,1-dioxide

4-Alkyl-2-methyl-3,4-diphenyl-1,2-thiazetidine 1,1-dioxide 5, 6 and 7 were obtained from 2-methyl-3,4-diphenyl-1,2-thiazetidine 1,1-dioxide 1 by reaction of its anion 4 with alkyl halides. cis- and trans-Configuration of the 4-alkylated products were determined by ¹H-nmr and NOE difference spectro-scopy studies.     

Sulfur-containing derivatives of five-membered cyclic sulfones. 2. Intramolecular cyclization of isothioureidothiolene 1,1-dioxide salts

cis-2-Imino-4,6,7,8-tetrahydrothieno[3,4-d]thiazole 5,5-dioxides were obtained by intramolecular cyclization of 4-isothioureido-2-thiolene 1,1-dioxide salts. The reaction of N-substituted thioureas with 4-bromo-2-thiolene 1,1-dioxide leads to 3-substituted cis-2-imino-4,6,7,8-tetrahydrothieno[3,4-d]thiazole 5,5-dioxides.See [1] for Communication 1.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 110–113, January, 1988.     

Synthesis of purine-like ring systems derived from 1,2,6-thiadiazine 1,1-dioxide

7-Amino-1H,4H-imidazo[2,3-c][1,2,6]thiadiazine 5,5-dioxide was prepared by a multi-step reaction sequence form 3,5-diamino-4H-1,2,6-thiadiazine 1,1-dioxide. 7-Amino-4H-furazano-[3,4-c][1,2,6]thiadiazine 5,5-dioxide was obtained by lead tetraacetate oxidation of 3,5-diamino-4-hydroxyimino-4H-1,2,6-thiadiazine 1,1-dioxide.     

Condensed thiolane 1,1-dioxide systems. 2. Brominated cis-perhydrothieno[3,4-d]oxazoles and imidazoles

Bromocyclization of 2-bromo-4-ureido-2-thiolene 1,1-dioxide has given perhydrothieno[3,4-d]oxazol-2-imino 5,5-dioxide, in which hydrogen atoms are absent from one of the -methylene groups. In weakly basic media, this undergoes conversion into the corresponding aminooxazoline. Treatment of an aqueous solution of 2-bromo-4-ureido-2-thiolene 1,1-dioxide with bases gives a mixture of perhydrothieno[3,4-d]imidazol-2-one 5,5-dioxides in which the bromine atoms have the exo- and endo-orientations. In all the bicyclic compounds, the two rings are cis-fused.For Communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1264–1268, September, 1988.     

Condensation of O-phenylhydroxylamine with some unsymmetrical heterocyclic ketones

2-Methyl-1,2,3,4-tetrahydrobenzofuro[2,3-c]pyridine, 3,4-dihydro-1H-thiopyrano[3,4-b]benzofuran, 2,3-dihydro-4H-thiopyrano[3,2-b]benzofuran 1,1-dioxide, and 1,3,4,5-tetrahydrothiepino[4,3-b]benzofuran 2,2-dioxide, respectively, were synthesized by condensation of O-phenylhydroxylamine with N-methyl-3-piperidone, tetrahydro-3-thiopyrone, tetrahydro-3-thiopyrone S,S-dioxide, and 4-thiepanone S,S-dioxide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 315–318, March, 1973.     

Crystal structure analysis of 3,4-dimethyl-2,5-dihydrothiophen-1,1-dioxide

The geometry of 3,4-dimethyl-2,5-dihydrothiophen-1,1-dioxide was determined by X-ray diffraction: cell dimensions are reported together with bond lengths and bond angles. While bond lengths are smaller than those for the homologue 3-methyl-2,5-dihydrothiophen-1,1-dioxide, bond angles are similar. TheMe-C₃-C₄-Me torsion angle is 5.1±0.5°. These results are consistent with its relatively slow rate of decomposition.

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Kristallstrukturanalyse von 3,4-Dimethyl-2,5-dihydrothiophen-1,1-dioxid

Zusammenfassung Die Geometrie von 3,4-Dimethyl-2,5-dihydrothiophen-1,1-dioxid wurde mittels Röntgendiffraktion bestimmt. Es werden die Dimensionen der Einheitszelle zusammen mit Bindungslängen und Bindungswinkeln berichtet. Die Bindungswinkel sind sehr ähnlich denen des homologen 3-Methyl-2,5-dihydrothiophen-1,1-dioxids, die Bindungslängen sind jedoch kürzer. DerMe-C 3-C 4-Me Torsionswinkel ist 5.1±0.5°. Diese Ergebnisse sind mit der relativ langsamen Zersetzungsgeschwindigkeit im Einklang.

     

Spiro[(2,3-dihydro-2-oxo-imidazo[1,2-a]pyridine)-3,3-(3,4-dihydro-2-methyl-4-oxo-2H-1,2-benzothiazine 1,1-dioxide)]-A novel product derived from piroxicam

A novel compound, spiro[(2,3-dihydro-2-oxo-imidazo[1,2-a]pyridine)-3,3-(3,4-dihydro-2-methyl-4-oxo-2H-1,2-benzothiazine 1,1-dioxide)] (3) , was isolated during an attempt to convert 4-hydroxy-2-methyl-N-(2-pyridinyl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide ( 1 ) (Piroxicam) to an O-trifluoromethanesulfonyl ester. A possible mechanism is offered to explain this unusual transformation.     

Differentiation of Constitutional Isomer of 2,2a,3,4-Tetrahydro- 4-methyl-2a-phenyl-2-(thiophen-2-yl)-1H-azeto[2,1-d][1,5] benzothiazepin-1-one-5-oxide and Fragmentations of 2,3-Dihydro- 2,4-diphenyl-1,5-benzothiazepine-1-oxide/-1,1-dioxide

Introduction Mostimportantantibioticspossessarepresen- tativestructureofaβ-lactamfusedfive-orsix- memberedheterocyclicringcontainingnitrogenand sulfuratoms.Forinstance,theeffectiveantibi- otics,penicillin,penamandpenem,havefusedthi- azolidine-β-lactam,andtheeffectiveantibiotics, cephalosporinandcephem,arefuseddihydroth- iazine-β-lactams[1].Recently,someβ-lactam derivativeshavealsobeenrecognizedasthein- hibitorsofhumanleukocytaseelastase[2]andserine protease[3].Thesynthesisofbicyclicβ-lact…     

Formation and Ring Contraction of Benzo[f][1,2]Thiazepine-1,1-Dioxides from and to Benzo[e][1,2]Thiazine-1,1-Dioxides

Alkoxide-promoted ring expansion of the novel ethyl 2-(6,7-dimethoxy-3-oxo-3,4-dihydrobenzo[e][1,2]thiazine-1,1-dioxide-2-yl)acetate 3a and analogous 4,4-diethyl derivative 3b and cyclization of methyl 2-[2-(phenylaminocarbonylmethyl sulfamoyl)-4,5-dimethoxyphenyl] acetate 9 to the corresponding new 3-carboxylates and 3-carboxanilide of 7,8-dimethoxy-4-hydroxy-2,5-dihydrobenzo[f][1,2]thiazepine-1,1-dioxide (5a,b and 10 respectively) is described. Compound 5a was deacylated upon treatment with sodium hydroxide followed by hydrochloric acid to give 7,8-dimethoxy-2,3-dihydrobenzo[f][1,2]thiazepine-1,1-dioxide-4 (5H)-one 8 and its N-ethyl derivative transferred to 6,7-dimethoxy-2-ethyl-3-oxo-3,4-dihydrobenzo[e][1,2]thiazine-1,1-dioxide 7 by the reaction with ethyl methyl ketone in the presence of pyrrolidine.     

Differentiation of Constitutional Isomer of 2,2a,3,4-Tetrahydro- 4-methyl-2a-phenyl-2- （thiophen-2-yl）- 1H-azeto [-2,1-d] [- 1,51benzothiazepin-1-one-5-oxide and Fragmentations of 2,3-Dihydro-2,4-diphenyl-1,5-benzothiazepine-l-oxide／- 1,1-d

Mass spectrometric behaviour of 2,2a, 3,4-tetrahydro-4-methyl-2a-phenyl-2- (thiophen-2-yl)- 1H-azeto [-2,1-d-J1-1,5-]benzothiazepin-l-one-5-oxide and 2,3-dihydro-2,4-diphenyl-1,5-benzothiazepine-l-oxide/-1,1-dioxide have been studied with the aid of mass-analyzed ion kinetic energy spectrometry and accurate mass measurements under electron impact ionization. The monooxide derivatives showed a tendency to eliminate an alkene or an oxygen atom. 1H-Azeto[-2,1-d][1,5]benzothiazepin-1-one-5-oxide could also eliminate the thiophen- 2-ylketene molecule via a reverse [-2 q- 2 ~ cycloaddition. 2,3-Dihydro-2,4-diphenyl- 1,5-benzothiazepine-1-oxide/-1, 1-dioxide could eliminate SO2 or SO, respectively. The structure of 2,2a, 3, 4-tetrahydro-4-methyl-2a-phenyl-2- (thiophen-2-yl)-1H-azeto 1-2,1-d-] [1,5 -] benzothiazepin-1-one-5-oxide was identified on the basis of its fragmentation. The identification was supported by the fragmentations of model compound, 2,3-dihydro-2,4-diphenyl-1,5-benzothiazepine-1-oxide/-1,1-dioxide.     

Azomethyne derivatives of 1,3-benzothiazine 1,1-dioxide

The Schiff's bases 2-alkyl-4-oxo-3,4-dihydro-2H-1,2-benzothiazine 1,1-dioxides have been synthesized for the first time, their structures in solution and in the crystalline state and their ability to form complexes have been investigated. The unusual condensation reaction of 1,2-benzothiazine 1,1-dioxide with ethyl orthoformate and 4-aminoantipyrine has been observed.     

Generation of strong, homochiral bases by electrochemical reduction of phenazine derivatives

Electrochemical reduction of enantiomerically pure amino- and alkoxy-phenazine derivatives forms strongly basic radical anions which give asymmetric induction in the conversion of 3,4-epoxytetrahydrothiophene-1,1-dioxide into the allylic ester with facile regeneration of the phenazine.     

Synthesis of 1-aryl-3,4-dimethylenepyrrolidines by the thermal elimination of sulfur dioxide

The reaction of 3,4-bis(bromomethyl)-2,5-dihydrothiophene 1,1-dioxide with arylamines to produce 5-aryl-1,3,4,6-tetrahydrothieno[3,4-c]pyrrole 2,2-dioxides was investigated. It was found that the bicyclic compound was obtained in good yields for arylamines with substituent groups with Hammett σ values of less than 0.40. These bicyclic compounds were thermally decomposed to produce the corresponding 1-aryl-3,4-dimethylenepyrrolidines in good yields. Several accompanying products of both of the above reactions were isolated and characterized.     

Synthesis of 2-S-dioxo isosteres of purine and pyrimidine nucleosides. II

The preparation of glucosyl and ribosyl derivatives of 3,4,5-triamino-2H-1,2,6-thiadiazine 1,1-dioxide ( 2 ), 7-amino-4H-furazano[3,4-c]- and 7-amino-1H, 4H-imidazo[2,3-c][1,2,6]thiadiazine 5,5-dioxide ( 3 and 4 respectively) is described. Different synthetic approaches have been used.     

Mass spectra of some phenyl- and chloro-substituted thianaphthenes and their sulfones

The mass spectra of 2,3-dichlorothianaphthene, 2-phenylthianaphthene, 2,3-diphenylthianaphthene, 3-chlorothianaphthene 1,1-dioxide, 2,3-dichlorothianaphthene 1,1-dioxide, 2-phenylthianaphthene 1,1-dioxide, 3-phenylthianaphthene 1,1-dioxide, and 2,3-diphenylthianaphthene 1,1-dioxide were studied. The fundamental mechanisms of fragmentation of molecules of these compounds under the influence of electron impact are examined.Translated from Khimiya Geterotsilicheskikh Soedinenii, No. 3, pp. 326–332, March, 1971.     

SYNTHESE DE NOUVEAUX DERIVES ORGANOPHOSPHORES BICYCLIQUES FONCTIONNELS

Abstract

Cycloaddition of dichlorophenylphosphine with 3,4-bis(methylene)-thiolane affords a bicyclic phospholenium salt; further reactions with water and dihydrogen sulfide give new series of bicyclic phospholenes.     

Condensed thiolane 1,1-dioxide systems. 3. Two modes of cyclization of N-substituted trans-3-chloro-4-thioureidothiolane 1,1-dioxides

Reaction of trans-3-chloro-A-aminothiolane 1,1-dioxide hydrochloride with aryl isothiocyanates gives, according to the base involved, cis-perhydrothieno[3,4-d]imidazole-2-thione 5,5-dioxides or the hitherto undescribed cis-2-aryliminoperhydrothieno 3,4-d] thiazole 5,5-dioxides.For Part 2, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1420–1423, October, 1988.     

The chemistry of 1,2,5-thiadiazoles V. Synthesis of 3,4-diamino-1,2,5-thiadiazole and [1,2,5] thiadiazolo[3,4-b]pyrazines

The o-diamine, 3,4-diamino-1,2,5-thiadiazole ( 2 ), was synthesized from 3,4-dichloro-1,2,5-thiadiazole ( 3 ) hy three methods. Aqueous glyoxal cyclized 2 into [1,2,5]thiadiazolo[3,4–6]-pyrazine ( 14 ). 3,4-Dichloro-1,2,5-thiadiazole 1,1-dioxide ( 18 ) reaeted with 2 to give 1,3-dihydro-bis[1,2,5]thiadiazolo[3,4-b:3′,4′-e]pyrazine 2,2-dioxide ( 19 ). The reaction of 2 with selenium oxyehloride led to [1,2,5]selenadiazolo[3,4-c] [1,2,5]thiadiazole ( 12 ). Ring closure of 2,3-diaminoquinoxaline ( 4 ) with thionyl chloride or selenium oxychloride gave [1,2,5]thiadiazolo-[3,4-b]quinoxaline ( 21 ) and [1,2,5]selenadiazolo[3,4-b]quinoxaline ( 22 ), respectively. Sulfurous acid reduced 21 to the 4,9-dihydro derivative 23 , which was reoxidized to 21 with chloranil. Aqueous hase hydrolyzed 21 to 4 via the hydrated intermediate 24 . Aqueous glyoxal cyclized 4 to the covalent hydrate of pyrazino[2,3-b]quinoxaline ( 26 ), 27 , which was dehydrated to 26 . Compound 26 underwent rapid addition of two alcohols in a process analogous to covalent hydration.     

Synthesis,Crystal Structure and Spectroscopic Properties of 1,2-Benzothiazine Derivatives:An Experimental and DFT Study

1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide(1) and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide(2) were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared(IR) spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory(DFT) at the 6-31G+(d) basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential(IP), Electron Affinities(EA) and coefficients of the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) of com- pounds 1 and 2 were simulated for the first time.