Synthesis of nitrogen-containing heterocycles. 8. Preparation and ring-opening of spiro[cycloalkane-[1′,2′,4′]triazolo[1′,5′-c]pyrimidine] derivatives

Diaminomethylene- and aminomethylthiomethylenehydrazones [2] of cyclic ketones 1–8 readily reacted with ethoxymethylenemalononitrile to give spiro[cycloalkane-1,2′-[1,2′,4′]triazolo[1,5′-c]pyrimidine-8′-carbonitrile] derivatives 12–19 through the electrocyclic reaction of the initially formed condensation products 26 in moderate to high yields. The spiro[cyclopentanetriazolopyrimidine] derivatives underwent ring-opening at the cycloalkane moiety upon heating in solution to give 2-alkyl-5-substituted-[1,2,4]triazolo[1,5-c]pyrimidine-8′-carbonitriles 20–23 . When an alkyl substituent was introduced into the cyclopentane ring, cleavage of the spiro compounds occurred preferentially at the cyclopentane moiety between the spiro carbon and the more branched one. In contrast, the cyclohexane ring, especially of spiro-5-amino-triazolopyrimidines 17 and 18 strongly resisted to ring-opening under similar conditions, but those of 5-methylthiotriazolopyrimidines 14 gave up to 17 percent of cleavage after prolonged heating in hot ethanol. 2-t-Butyl-5-methylthio-2,3-dihydro[1,2,4]triazolo[1,5-c]pyrimidine-8-carbonitrile 25 [R³ = C(CH₃)₃] was highly susceptible to the cleavage even at room temperature and produced the corresponding 2-unsubstituted triazolopyrimidine 24 with loss of the t-butyl group.     

Studies on Organophosphorus Compounds: Synthesis and Reactions of Some New 5′-Cyano-2′-(4-methoxyphenyl)spiro[cycloalkane-1,6′-[1,3,2]thiazaphosphixane]-2′,4′-disulfide Derivatives

2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson's Reagent, LR, 1 ) reacts with cycloalkylidenecyanothioacetamides ( 2 and 3 ) to give 5'-cyano-2'-(4-methoxyphenyl)spiro [cyclopentane(cyclohexane)-1,6'-perhydro-[1,3,2]thiazaphosphixane]-2',4'-disulfide ( 4 and 5 ). The reaction of compounds 4 and 5 with f -halo compounds led to the formation of the substituted thio-compounds 6a-e and 7a-e , respectively, these compounds, upon treatment with sodium ethoxide, produce the corresponding thienothiazaphosphixine derivatives 8a-e and 9a-e respectively. Compounds 8a-e and 9a-e react with LR under different reaction conditions to give polyfused heterocyclic compounds 10a-d and 11a-d respectively. Treatment of compounds 8b and 9b with CS 2 and (CH 3 ) 2 SO 4 gave the corresponding dithiocarbamate methyl ester derivatives 12 and 13 , respectively, which on treating with hydrazine hydrate yielded compounds 14 and 15 respectively. Compounds 14 and 15 reacted with LR to yield compounds 16a , b and 17a , b respectively.     

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.     

SYNTHESIS AND REACTVITY OF N-[N-PHOSPHORAMIDO-1H-BENZIMIDAZOL-2-YL] IMIDATES

N-(-1H-Benzimidazol-2-yl) imidates 1a–c react with chlorophosphoramide to give the N-[-1-N,N,N′,N′-tetramethylphosphoramidoyl-1H-benzimidazol-2-yl]-imidates 2a–c or with dichlorophosphoramide to yield the bis[(N-1-benzimidazol-2-yl)-imidate] phosphoramide derivatives 3a–b. The reaction of compounds 2a–c toward primary amines is studied. The obtained amidine derivatives 4a–b were unambiguously characterized by different spectroscopic techniques (IR, ¹H, ¹³C, and ³¹P NMR, and in some cases MS).     

Liquid-crystalline 1,4-disubstituted cycloheptanes

Abstract

A new series of liquid-crystalline alicyclic compounds, the 1,4-disubstituted cycloheptane derivatives, have been synthesized. The physicochemical and electrooptical characteristics of the new mesogens have been compared with those of analogues in the cyclopentane and cyclohexane series, including cyclohexanes having a side methyl group.     

Synthesis and molecular structure of 2,4,8a-triaryl-6-methylperhydro[1,3,2]dioxaborinino[5,4-c]pyridines

Condensation of arylboronic acids with 4-hydroxy-3-(-hydroxybenzyl)-1-methyl-4-phenylpiperidine afforded 2,4,8a-triarylperhydro[1,3,2]dioxaborinino[5,4-c]pyridines. The molecular structure of 6-methyl-2,4,8a-triphenylperhydro[1,3,2]dioxaborinino[5,4-c]pyridine was established by X-ray diffraction analysis.     

1,3-Disubstitutedpyrazole-4-caboxaldehyde in Heterocyclic Synthesis: A Novel Synthesis of Pyridine-2(1H)-thione and Fused Nitrogen and/or Sulfur Heterocyclic Derivatives

Pyridine-2(1H)-thione 5 was synthesized from the reaction of 3-[3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl]-1-phenylpropenone (3) and cynothioacetamide (4). Compound 5 reacted with halogented compounds 6a–e to give 2-S-alkylpyridine derivatives 7a–e, which could be in turn cyclized into the corresponding thieno[2,3-b]-pyridine derivatives 8a–e. Compound 8a reacted with hydrazine hydrate to give 9. The latter compound reacted with acetic anhydride (10a), formic acid (10b), acetic acid, ethyl acetoacetate, and pentane-2,4-dione to give the corresponding pyrido[3′,2′:4,5]thieno-[3,2-d]pyrimidine 13a,b, pyrazolo[3′,4′:4,5]thieno[3,2-d]pyridine 14 and thieno[2,3-b]-pyridine derivatives 18 and 20, respectively. Alternatively, 8c reacted with 10a,b and nitrous acid to afford the corresponding pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine 24a,b and pyrido[3′,2′:4,5]thieno[3,2-d][1,2,3]triazine 26 derivatives, respectively. Finally compound 5 reacted with methyl iodide to give 2-methylthiopyridine derivative 27, which could be reacted with hydrazine hydrate to yield the corresponding pyrazolo[3,4-b]-pyridine derivative 29.     

2,4,8,10-TETRASUBSTITUTED DIBENZO[d,f][1,3,2]DIOXAPHOSPHEPINS

Abstract

The synthesis of the dibenzo[d,f][1,3,2]dioxaphosphepin ring system from substituted biphenyl-2,2′-diols and alkylphosphonous dichlorides is described. The NMR spectral data are consistent with either rapidly interconverting ring conformers or a static non-planar ring conformation.     

Synthesis of 5-glycopyranosylamino-pyrano[2,3-d]pyrimidin-2-one derivatives

Summary Three series of 3-substituted 5-glycopyranosylamino pyrano[2,3-d]pyrimidin-2-one derivatives,3 a–c,4 a–c, and5 a–c have been prepared by treatment of the corresponding 1,4-dihydro-6-glycopyranosylamino pyrimidin-4-ones1 a–c with malonic, methyl malonic and ethyl malonic acids, respectively.

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Synthese von Derivaten des 5-Glucopyranosylaminopyrano[2,3-d]pyrimidin-2-on

Zusammenfassung Es wurden drei Serien von 3-substituierten 5-Glucopyranosylaminopyrano[2,3-d]pyrimidin-2-onen (3 a–c,4 a–c und5 a–c) mittels Behandlung der entsprechenden 1,4-Dihydro-6-glucopyranosylamino-pyrimidin-4-one (1 a–c) mit Malon-, Methylmalon- bzw. Ethylmalonsäure dargestellt.

     

SOME ASPECTS ON ACYCLO- 4-[QUINAZOLIN-3-YL]BENZENESULFONAMIDE NON-NUCLEOSIDES SYNTHESIS

The reaction of 4-[1,2,3,4-tetrahydroquinazolin-2,4-dion-3-yl]benze-nesulfonamide 4 and 4-[2-thioxo-1,2,3,4 tetrahydroquniazolin-4-on-3-yl]benznesulfonamide 5 with chloromethylethyl ether, chloromethylbenzyl ether, and (2-acetoxyethoxy)methyl bromide afforded compounds 7a–c, 8a,b, and 13 which are analogues to MKC-442, TNK 561, and HEPT.     

ISOQUINO[2,1-c][1,3,2] BENZODIAZAPHOSPHORINE DERIVATIVES: NEW POTENTIAL AGENTS FOR CANCER CHEMOTHERAPY

Abstract

Three derivatives of 2-chloro-5,8,9,13b-tetrahydro-5-methyl-6H-Isoquino[2,1 -GI[1,3,2]benzodiazaphosphorine 6-oxides as well as its sulphides were synthesized with the aim of evaluating their antitumor properties. Three of the twenty one compounds were found to be significantly active (inhibition of tumor growth > 80%) in the Ehrlich ascites carcinoma screen. Several structure-activity relationships were indicated for antitumor activity in this screen. An aziridinyl substituted derivative, bis-(2-chloroethyl)amino substitution (3) also exhibited significant activity against the growth of P-388 lymphocytic Leukemia cells in male BDF, mice (% T/C = 147; % T/C > 125 is considered significant). The reference for activity comparison is cyclophosphamide or cytoxan i.e. [bis(2-chloroethyl)aino]-5,6-dihydro-2H-1,3,2-oxazaphosphorinane 2-oxide [having TIC × 100 = 339 at a dose of 65 mg/kg]     

Synthesis and Reactions of Some New Heterocyclic Compounds Related to Pyrrolylthieno[2,3-d]pyrimidines and Thieno[2,3-d][4,5-d]dipyrimidines

Abstract

Condensation of ethyl-5-amino-2,4-diphenylthieno[2,3-d]pyrimidine-6-carboxylate (3a) with 2,5-dimethoxy tetrahydrofurane in acetic acid gives the corresponding 5-pyrrolyl derivative4, which in turn could be easily reacted with hydrazine hydrate in ethanol yielding the carbohydrazide derivative5. Reaction of5 with aromatic aldehydes, acetylacetone, carbon disulfide or phenylisothiocyanate gave pyrrolyl derivatives6,7,8,9 respectively. On the other hand, condensation of 5-(1-pyrrolyl)-6-acetyl-2,4-diphenylthieno[2,3-d]pyrimidine11 with benzaldehyde afforded the corresponding chalcone12, which on treatment with hydrazine hydrate, phenyl hydrazine, or thiourea gave the pyrazolinyl derivatives13,14 and pyrimidinyl derivative15, respectively. Furthermore some new pyrimidothienopyrimidne16,17a–d,19,20a–c were obtained using 5-amino-carboxamide3c as starting material.     

L-Proline catalyzed three component synthesis of pyrano[2,3-c]pyrazole-5-carbonitrile derivatives and in vitro antimalarial evaluation

An efficient one-pot synthesis of 6-amino-4-(2-chloroquinolin-3-yl)-3-methyl-2, 4-dihydro-pyrano[2,3-c]pyrazole-5-carbonitrile derivatives (4a–f)(5a–f) by three component reactions of 2-chloroquinolin-3-carbaldehyde derivatives, malanonitrile, and 3-methyl pyrazolin-5-one derivatives catalyzed by L-proline in ethanol medium under mild conditions is established. The synthesized compounds were evaluated for antimalarial activity and the LC₅₀/LC₉₀ values were described. Compounds 4d, 5d, and 5f exhibits good antimalarial activity when compared to other pyrano[2,3-c]pyrazole scaffolds.     

Specific Features of Reaction of 2-R-Benzo[e][1,3,2]dioxaphosphinin-4-ones with Perfluorodiacetyl. Synthesis and Steric Structure of 4′,5′-Bis(trifluoromethyl)-4-oxo-2-(2,2,3,3-tetrafluoropropoxy)-2λ 5-spiro[benzo[e][1,3,2]dioxaphosphinine-2,2′-[1,3,2]dioxaphosphole]

2-R-benzo[e][1,3,2]dioxaphosphinin-4-ones react with perfluorodiacetyl under mild conditions to form relatively labile spirophosphoranes containing a 1,3,2-dioxaphosphole ring. These compounds gradually convert to more stable 2-R-4,5-bis(trifluoromethyl)-1,3,2λ⁵-dioxaphosphole 2-oxides and diastereometic 2-R-4-(trifluoroacetyl)-4-(trifluoromethyl)benzo[f][1,3,2λ⁵]dioxaphosphepine 2-oxides, whose structure was confirmed by means of NMR and IR spectroscopy. The structure of 4′,5′ -bis(trifluoromethyl)-4-oxo-2-(2,2,3,3-tetrafluoropropoxy)-2λ ⁵-spiro[benzo[e][1,3,2]dioxaphosphinine-2,2′-[1,3,2]dioxaphosphole] was confirmed by X-ray diffraction analysis.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 587–599.Original Russian Text Copyright © 2005 by Konovalova, Mironov, Ivkova, Zagidullina, Gubaidullin, Litvinov, Kurykin.     

Preparation and crystal structure of 1,1-tetramethylethylenedioxy-3,4-diphenyl-6-trichloromethyl-2,5,7,1-trioxaphosphabicyclo[2.2.1<Superscript>1,4</Superscript>]heptane and 2-(1-hydroxy-2,2,2-trichloroethoxy)-4,4,5,5-tetramethyl- 2-oxo-1,3,2-dioxaphospholane

The state of the art of chloral applications in the chemistry of tricoordinate phosphorus derivatives has been analyzed. The highly stereoselective reaction of 4,4,5,5-tetramethyl-2-(2-oxo-1,2-diphenylethoxy)-1,3,2-dioxaphospholane with chloral has been shown to afford a caged phosphorane with the phosphorus–carbon bond, 1,1-tetramethylethylenedioxy-3,4-diphenyl-6-trichloromethyl-2,5,7,1-trioxaphosphabicyclo- [2.2.1^1,4]heptane. Structure of the phosphorane and its hydrolysis product, 2-(1-hydroxy-2,2,2-trichloroethoxy)- 4,4,5,5-tetramethyl-2-oxo-1,3,2-dioxaphospholane, has been elucidated by X-ray diffraction analysis.     

Synthesis of fluorinated 2,6-heptanediones and 2-oxa-6- azabicyclo[2.2.2]octanes from 1,4-dihydropyridines

Electrophilic fluorination of Hantzsch-type 1,4-dihydropyridines with Selectfluor^® led to the formation of new fluorinated 2,6-heptanediones - dialkyl 2,4-diacetyl-2,4-difluoro-3-phenylpentanedioates. Novel 2,6-heptanedione derivatives in reaction with hydrazine hydrate easily form 6-amino-4,7-difluoro-3-hydroxy-1,3-dimethyl-5-oxo-8-phenyl-2-oxa-6-azabicyclo[2.2.2]octanes instead of the corresponding diazepine derivatives. The obtained 2-оxa-6-azabicyclo[2,2,2]octanes are thermally stable at the temperatures below 50°С. At higher temperatures rearrangement of 2-oxa-6-azabicyclo[2,2,2]octanes offers new fluorine-containing pyrazolinone derivatives - alkyl esters of 2-fluoro-2-((4-fluoro-3-methyl-5-oxo-4,5-dihydro-1H-pyrazol-4-yl)(phenyl)methyl)-3-oxobutanoates.     

Activated Nitriles in Heterocyclic:Synthesis Novel Syntheses of Imidazo[2,1-b]-1,3-Thiazine Derivatives

Abstract

Several new imidazo[2,1-b]-1,3-thiazine derivatives 4a–c, 8a–c, and 11a–c were synthesised via the reaction of 5,5-diphenyl-2-thiohydantoin (1) with αβ -unsaturated nitriles 2a–c, 5a–c, and 9a–c. The structures of the products were established on the basis of elemental analyses, IR, and ¹H-NMR spectral data.     

Reaction of 2-R-benzo[<Emphasis Type="Italic">d</Emphasis>]-1,3,2-oxazophosphorin-8-one with hexafluoroacetone. Synthesis and steric structure of 3-phenyl-9,9-bis(trifluoromethyl)-2-ethoxybenzo[<Emphasis Type="Italic">d</Emphasis>]-1,3,2-oxazaphosphepine-2,8-dione

Reaction of hexafluoroacetone with 2-R-benzo[d]-1,3,2-oxazophosphorin-8-ones leads to the formation of seven-membered nitrogen-containing heterocycles, the derivatives of 3-phenyl-9,9-bis (trifluoromethyl)benzo[d]-1,3,2-oxaza-phosphepine-2,8-diones. Steric structure of 2,3-diphenyl-9,9-bis (trifluoromethyl)-benzo[d]-1,3,2-oxazaphosphepine-2,8-di-one was established by X-ray structural analysis. By hydrolysis of the phosphepines a functionally substituted fluorinated ketone, 2-hydroxy-1-(2′-phenylamino)phenyl-2-trifluoromethyl-3,3,3-trifluoro)propan-1-one, was obtained.     

A Convenient Route to 1,3,4-Thiadiazoles,Thiazolidinone, Thiazoles,Pyridones, Coumarins,Triazolo[5,1-c]triazines,and Pyrazolo[5,1-c]triazines Incorporating Pyrazolone Moiety and Their Use as Antimicrobial Agents

Condensation of 4-acetyl-5-methyl-2-phenyl-2,4-dihydropyrazol-3-one (1) with hydrazine derivatives (2a–d) afforded hydrazone derivatives (3a–d), which reacted with alkyl halides 4a–c to give bis(alkylthio)methylene derivatives (5a–e). Also, 3a,b reacted with hydrazonyl halides 6a–d to give 1,3,4-thiadiazole (7a–d). Cyclization of 3c with ethyl bromoacetate and haloketones gave thiazolidinone and thiazole derivatives (8, 10a,b) respectively. Treatment of hydrazone (3d) with benzylidine malononitrile 13a,b gave pyridine (14a,b). In addition, cyclocondensation of 3d with phenolic aldehydes furnished coumarin derivatives (16a–c). Coupling of 3d with heterocyclic diazonium salts gave triazol[5,1-c]triazine (20) and pyrazolo[5,1-c]triazine (22). Some of the prepared products showed potent antimicrobial activity.     

Syntheses of 1,5-Benzothiazepines-Part XXXI: Syntheses and Antimicrobial Studies of 10-Substituted-7- (monochlorophenyl/dichlorophenyl)-6H-6a,7-dihydro-6-phenyl[1]benzopyrano[3,4-c]-[1,5]benzothiazepines

Abstract

Two flavindogenides, 3-(2-chlorobenzylidene)-flavanone and 3-(2,4-dichloro- benzylidene)-flavanone reacted with six 5-substituted-2-aminobenzenethiols, the substituents being fluoro, chloro, bromo, methyl, methoxyl, and ethoxyl, to give respective 12 new compounds, 10-substituted-7-(2-chlorophenyl/2,4-dichlorophenyl)- 6H-6a,7-dihydro-6-phenyl[1]benzopyrano[3,4?c][1,5]benzothiazepines (5a–l) in 60–70% yields. The products were characterized on the basis of microanalytical data for elements and IR, ¹ H, and ¹³ C NMR and mass spectral studies. All the synthesized compounds were evaluated for their antimicrobial activity against the bacteria,Escherichia coli and GFC,and the fungi,Aspergillus niger, Aspergillus flavus,and Curvularia lunata.