Showing papers in "Phosphorus Sulfur and Silicon and The Related Elements in 2007"

A Novel Synthesis of Some New Pyrimidine and Thiazolopyrimidine Derivatives for Anticancer Evaluation

Abstract: Diaryl-oxiran-2-yl methanones ( 2 ) were prepared and reacted with thiourea to give 2-thioxo-tetrahydro-pyrimidine-5(2H)-ones ( 3 ).The latter compounds reacted with bromoacetic acid to afford the title compounds ( 4 ). Also some new derivatives were prepared from the reaction of compounds ( 3 ) and ( 4 ) with different reagents. Compounds ( 3 ) were glycosidated with 2,3,4,6-tetra-O-acetyl-α -D-glucopyranosylbromide (α -ABG) to afford the corresponding nucleosides.

Silica-Gel Catalyzed Stereoselective Conversion of Stabilized Phosphorus Ylides to Dialkyl ( Z )-2-(2-Methoxycarbonyl-phenoxy)-2-butenedioates in Solvent-Free Conditions

Abstract: Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by methyl salisylate leads to vinyltriphenylphosphonium salts, which undergo a Michael addition reaction with a conjugate base to produce dialkyl 2-(2-methoxycarbonyl-phenoxy)-3-(triphenylphosphoranylidene)butanedioates. Silica-gel powder was found to catalyze the stereoselective conversion of dialkyl 2-(2-methoxycarbonyl-phenoxy)-3-(triphenylphosphoranylidene)butanedioates to dialkyl (Z)−2−(2−methoxycarbonyl−phenoxy)−2−butenedioates in solvent−free conditions under microwave (0.5 KW, 3 min) and thermal (90°C, 90 min) conditions.

A Novel and Effective Synthetic Approach to 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) Derivatives

Abstract: DOPO and its derivatives generally exhibit an outstanding performance as flame retardants in various polymers. Starting from trivalent 10-alkoxy-10H-9-oxa-10-phosphaphenanthrenes, a broad range of DOPO derivatives was synthesized via transesterification with aliphatic alcohols and subsequent Michaelis-Arbuzov rearrangement using catalytic amounts of p-toluenesulfonic acid methylester. Due to the considerable differences in the nature of the alcohols employed, several procedures for processing them are presented.

Dipotassium Hydrogen Phosphate-Catalyzed Synthesis of Dialkyl 2-(4-Fluoro-Phenoxy)-2-Butendioates From Stabilized Phosphorus Ylides in Solvent-Free Conditions

Abstract: Protonation of the highly reactive 1:1 intermediates, produced in a reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by 4-fluorophenol leads to vinyltriphenylphosphonium salts, which undergo a Michael addition reaction with a conjugate base to produce dialkyl 2-(4-fluoro-phenoxy)-3-(triphenylphosphoranylidene)butanedioates. Dipotassium hydrogen phosphate powder was found to catalyze the conversion of dialkyl 2-(4-fluoro-phenoxy)-3-(triphenylphosphoranylidene)butanedioates to dialkyl 2-(4-fluoro-phenoxy)-2-butenedioates in solvent-free conditions under microwave (0.5 KW, 3 min) and thermal (90°C, 60 min) conditions.

Synthesis of Ursolic Phosphonate Derivatives as Potential Anti-HIV Agents

Abstract: In order to search for new anti-tumor and anti-viral agents, a series of α-aminophosphonate conjugates of 3-O-β-acetyl ursolic acid were prepared. Their biological activities as cytotoxic and anti-HIV agents were evaluated. The preliminary bioassays indicate that synthesized compounds 7a–j have anti-HIV activity (targeting HIV-1 gp120 and CD4) and no cytotoxicity on HT-29 cells (human colon adenocarcinoma cell line).

Synthesis and Fungicidal Activity of Some New 4H-Chromen-4-ones Containing Some 1,3-Thiazole, 1,3-Thiazine, 1,2,4-Triazole and 1,2,4-Triazine Moieties

Abstract: The potassium salt of carbamodithioic acid derivative 3 reacted with some electrophiles reagents to afford the 2-thioxo-1,3-thiazoles 4–5 and 2-thioxo-1,3-thiazines 6–7 derivatives. Heterocyclization of compound 3 with amino-mercapto compounds 8–9 and/or hydrazine derivatives 12–13 yielded 3-thioxo-1,2,4-triazoles 10–11 and 3-thioxo-1,2,4-triazines 14–15 , respectively. Structures of the products have been determined by elemental and spectral methods. All the new compounds have been screened for their fungicidal activity.

Synthesis of Some New Substituted 2-Mercaptoquinazoline Analogs as Potential Antimicrobial Agents

Abstract: A new series of substituted 2-mercapto-3-(4-chlorophenyl)-6-iodo-3H-quinazolin-4-ones was prepared and screened for antimicrobial activity. Compounds 11, 13, 17, and 18 showed a remarkably broad spectrum of antimicrobial activity and could be useful as templates for further development through modification or derivatization to design more potent antimicrobial agents. A detailed synthesis of new 2-mercaptoquinazolinones and their antimicrobial screening are reported.

One-Pot Synthesis of Fluorine-Containing Alkenes from In Situ-Generated Stabilized Phosphorus Ylides

Abstract: Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by 4-(trifluoromethyl)benzyl alcohol leads to vinyltriphenylphosphonium salts, which undergo a Michael addition reaction with a conjugate base to produce the corresponding fluorine-containing stabilized phosphorus ylides. An intermolecular Wittig reaction of the fluorine-containing stabilized phosphorus ylides with ninhydrin leads to the corresponding highly electron-poor fluorine-containing alkenes.

Utility of Nitriles in Synthesis of Pyrido[2,3-d]pyrimidines, Thiazolo[3,2-a]pyridines, Pyrano[2,3-b]benzopyrrole, and Pyrido[2,3-d]benzopyrroles

Abstract: 3-Aryl-2-cyanoacrylonitriles ( 1a , b ) reacted with 6-aminothiouracil, 2-ethoxy carbonylmethyl-4-oxo-Δ2-thiazoline, 2-cyanomethyl-4-oxo-Δ2-thiazoline and indan-2-one to give pyrido[2,3-d]pyrimidines, thiazolo[3,2-a]pyridines, pyrano [2,3-b]benzopyrrole and pyrido[2,3-b]benzopyrrole, respectively. The IR, MS and 1H-NMR of the synthesized compounds were discussed. The antimicrobial activity of some of the synthesized compounds was tested.

Synthesis of Some New Pyrimidine Derivatives of Expected Antimicrobial Activity

Abstract: 2-(2-Arylvinyl)-6-methyl-4-mercapto-5-acetylpyrimidine derivatives 3 a − d , were synthesized form the reaction of the appropriate isothiocyanate derivatives 1 with α, β -unsaturated aminoketone 2 . Compound 3 was alkylated with methyl iodide, ethyl chloroacetate and/or bromosugar to afford 6 , 9 , and 22 a − c respectively. Cyanoethylation of 3 b afforded 6 b which upon cyclization with hydrazine hydrate gave pyrazolopyrimidine 7 . Bromination of 6 b gave dibromo compound 8 . Thieno[2,3-d]pyrimidines 10 and 12 were obtained by ring closure of the alkylated product 9 with TEA/EtOH and/or through cyclization of the hydrazide 11 with NaOEt/EtOH. While, Thieno[2,3-d]pyrimidine 14 was obtained directly by alkylation of 3 b with chloroacetone in both TEA/EtOH and Na2CO3 solution. The cycloaddition products 15 and 16 were obtained by reaction of 3b with diethylmaleate and/or maleic anhydride. Formation of 1,3,4-oxadiazole 17 , pyrazoles 18 and 19 where obtained by treating the hydrazide 11 with carbon disulphid...

Synthesis, Structure Elucidation, and Biological Evaluation of Some Fused and/or Pendant Thiophene, Pyrazole, Imidazole, Thiazole, Triazole, Triazine, and Coumarin Systems Based on Cyanoacetic 2-[(Benzoylamino)thioxomethyl] Hydrazide

Abstract: Aiming to produce cyclized systems with potential bioactivity, a variety of fused and/or pendant thiophene, pyrazole, imidazole, thiazole, triazole, triazine, and coumarin systems were synthesized based on a cyanoacetic 2-[(benzoylamino)thi- oxomethyl] hydrazide precursor. The structure of the synthesized compounds was established based on elemental analysis and spectral data. The antibacterial and antifungal activities of the compounds are discussed and evaluated.

Synthesis of Novel Arylthio Derivatives of Mucochloric Acid

Abstract: Stable reaction products of mucochloric acid with aromatic and heterocyclic thiols were synthesized and characterized. Under basic conditions the reactions proceeded with the substitution of the chlorine atom(s) by arylthiogroup(s), while in an acidic medium the hydroxy group at C 5 was substituted. Different types of new sulfur-containing products of di- and trisubstitution on the basis of mucochloric acid were obtained. In one case a new acyclic product—di-p-tolyl-2,3-bis-(p-tolylthio)butanedithioate—was isolated. The structure of all synthesized compounds was confirmed by IR, 1 H, and 13 C NMR spectroscopy; three compounds were characterized by single crystal X-ray diffraction.

One Pot Synthesis of Biodynamic Bisamidothiophosphonates Incorporating Asymmetric Phosphorus Atom

Abstract: N-alkyl-2-pyridinylidenamido(phenyl)chlorothiophosphonates have been generated in situ by oxidative phosphorylation of N-alkyl-2-aminopyridinium halides through the intermediacy of functionalized halophosphines. As evident from the proton NMR spectroscopy, the generated chiral system had induced diastereotopicity in the geminal protons attached to a prochiral carbon atom. Due to the presence of an active chlorine atom, they have been used as precursors for the synthesis of novel bisamidothiophosphonates. The bioactive nature of these compounds has been established after bioassay against the fungi Alternaria alternata, Aspergillus flavus, Aspergillus niger, and Fusarium oxysporum and the insect Holotrichea Consanguinea.

Synthesis, Anti–HIV, and Antifungal Activity of New Benzensulfonamides Bearing the 2,5-Disubstituted-1,3,4-Oxadiazole Moiety

Abstract: A series of novel chiral and achiral N-[1-(1,3,4-oxadiazol-2ylthio)alkyl]-4-methyl/chloro/methoxybenzenesulfonamides 5a–l were prepared by the reaction of 4-(4-methyl, chloro, methoxyphenylsulfonamido)alkyl carboxylic acid hydrazides 4a–l with CS2 and KOH. Another series of new secondary benzenesulfonamides 10a–j and bis-benzenesulfonamides 11a–j have been synthesized by a new approach using Et3N and dimethylaminopyridine. All synthesized compounds were characterized by physical, microanalytical, and spectral data. Some of the synthesized compounds were screened in vitro for their anti–HIV and antifungal activities.

Synthesis and Reactions of Some New Thiobarbituric Acid Derivatives

Abstract: A series of novel thiobarbituric acid derivatives 3a–c , 5, and 12 were synthesized via the reaction of 4-benzoyl-1-cyanoacetylthiosemicarbazide ( 1 ) or its derivatives 2a–c , 9 with malonic acid and acetyl chloride. Coupling of thiobarbituric acid derivatives 3a-c and 5 with aromatic diazonium chlorides furnished a new series of the corresponding bisarylhydrazo-thiobarbituric dyes 4a–c . The reaction of 5 with cyclohexanone and sulfur under Gewald reaction condition afforded thieno[2,3-d]pyrimidine derivative 21 , that condensed with p-anisladehyde to give 5-arylidene thiobarbituric acid derivative 22 . The reaction of 1 with phenyl isothiocyanate afforded the non-isolable adduct 23 which was used as a key intermediate for the synthesis of polyfunctionally substituted thiazolidinone and thiobarbituric ring systems.

Reaction of Hydrazonoyl Halides 511: A Facile Synthesis of 5-Arylthiazoles and Triazolino[4,3- a ]pyrimidines as Antimicrobial Agents

Abstract: [5-Substituted 2-(3-phenyl-5-substituted 2-pyrazolinyl)(1,3-thiazol-4-yl)]phenyldiazenes, triazolo[3,4-a]pyrimidines, and 2,3-dihydro-1,3,4-thiadiazoles were synthesized with good yields from reactions of hydrazonoyl halides with 5-substituted-3-phenyl-4,5-dihydropyrazole-1-carboximidothionic acid, pyrimidine-2-thione, methyl carbodithioate, respectively. All structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, and alternative synthesis methods. Newly developed compounds are capable of inhibiting the growth of bacteria (gram positive and gram negative) greatly.

Coordination Behavior of Unsymmetrical Ligand Complexes of Diorganotin and Diorganosilicon Derived From Schiff Bases

Abstract: Hexacoordinated organotin and organosilicon derivatives have been prepared and characterized by analytical and spectroscopic techniques including UV, IR, 1 H NMR, and 13 C NMR spectra. The ligands used in the present account were derived by the condensation of thiosemicarbazide and 1H-Indol-2,3-dione, 1,3-dihydro-3-[2-(4-fluorophenyl)-2-oxo-ethylidene]-2H-indol-2-one, and 1,3-dihydro-3-[2-(4-fluoro-3-methyl-phenyl)-2-oxo-ethylidene]-2H-indol-2-one under microwave irradiation as well as by conventional heating. Newly synthesized complexes with their corresponding ligands were tested for their antifungal and antibacterial activities. The aim of the present study is to synthesize some novel ecofriendly fungicides and bactericides that have important pharmacodynamic significance.

Synthesis, Reactions, and Antimicrobial Activity of Some Fused Thieno[2,3-d]pyrimidine Derivatives

Abstract: Some new indeno[1′,2′ :4,5]thieno[2,3-d]pyrimidines were prepared from the reaction of 2-aminoindeno[2,1-b]thiophene-3-carbonitrile ( 1 ) with different reagents. Also, some indeno[1′,2′ :4,5]thieno[3,2-e]tetrazolo[1,5-c]pyrimidines and indeno[1′,2′ :4,5]thieno[3,2-e][1,2,4]triazolo[4,3-c]pyrimidines and their isomeric [1,2,4]triazolo[1,5-c]pyrimidines were prepared. The antimicrobial evaluation of some prepared products showed that many of them revealed promising antimicrobial activity.

Synthesis and Characterization of O,O′-(o-, m-, or p-Ditolyl) Dithiophosphate Ligands

Abstract: O,O ′-(ortho-, meta-, or para-ditolyl) dithiophosphate ligands have been isolated as triethylammonium salts, (o-, m-or p-CH 3 C 6 H 4 O) 2 PS 2 HNEt 3 , by an auto-catalytic reaction of cresols with P 2 S 5 in the presence of Et3N in a 4:1:2 molar ratio in toluene under anhydrous conditions. These triethylammonium salts could be converted into sodium/ammonium salts, (o-, m-, or p-CH 3 C 6 H 4 O) 2 PS 2 Na/NH 4 , by their direct reaction with sodium metal in equimolar ratio or passing dry ammonia gas in toluene. These salts were characterized by elemental analyses (C, H, N, and S) and mass, IR, and NMR ( 1 H, 13 C, and 31 P) spectroscopic studies.

Synthesis and Antimicrobial Activity of Some Thiazolyl-Pyrazoline Derivatives

Abstract: Some 1-(4-aryl-2-thiazolyl)-3-(2-thienyl)-5-aryl-2-pyrazoline derivatives ( TP 1–28 ) were synthesized by reacting substituted 3-(2-thienyl)-5-aryl-1-thiocarbamoyl-2-pyrazolines ( P 1–7 ) with phenacyl bromides in ethanol. Structures of the synthesized compounds were confirmed by elemental analyses and IR, 1 H-NMR and MS-FAB+ spectral data. Their antimicrobial activities against Escherichia coli (NRRL B-3704), Staphylococcus aureus (NRLL B-767), Salmonella typhimurium (NRRL B-4420), Bacillus cereus (NRRL B-3711), Listeria monocytogenes (Ankara University, Faculty of Veterinary, Ankara, Turkey), Aeromonas hydrophila (Ankara University, Faculty of Veterinary, Ankara, Turkey), Candida albicans, and Candida glabrata (isolates obtained from Osmangazi University, Faculty of Medicine, Eskisehir Turkey) were investigated. A significant level of activity was illustrated.

Silica-Supported 2,4,6-Trichloro-1,3,5-triazine as an Efficient Reagent for Direct Conversion of Carboxylic Acids to Amides Under Solvent-Free Conditions

Abstract: A very simple and efficient solvent-free method for the direct conversion of carboxylic acids to primary, secondary, tertiary alkyl, and aromatic amides in the presence of the corresponding ammonium salts, silica-supported 2,4,6-trichloro-1,3,5-triazine, and triethylamine is described. The reactions proceed rapidly at room temperature, and the products are obtained in moderate to excellent yields.

A New Approach to the Synthesis of Fused Pyrazoles: The Synthesis of New Pyrazolo [4,3-e][1,2,4]triazolo-[4,3-a]pyrimidine-4(5H)-imines

Abstract: A new route for the synthesis of pyrazolo[4,3-e][1,2,4]triazolo[4,3-a]pyrimidine-4(5H)-imines has been delineated through heterocyclization of suitably functionalized pyrazoles with phenylisothiocyanate followed by methylation, nucleophilic displacement with hydrazine, and finally cyclocondensation with orthoesters.

Synthesis, Characterization, and Antiviral Activities of Pyridopyrazolotriazines

Abstract: A pyrazolo[3,4-b]pyridine-5-carbonitrile derivative was diazotized to give the corresponding diazonium salt, which was used as a good synthon to synthesize pyrido[2′,3′:3,4]pyrazolo[5,1-c]triazines via its coupling with several active hydrogen-containing reagents, e.g., 2,4-pentandione, ethyl 3-oxo-butanoate, diethylmalonate, malononitrile, 2-cyanoethanethioamide, and ethyl cyanoacetate. Also, it reacted with phenylisothiocyanate to afford the corresponding pyrazolo[3,4-b]pyridin-3-ylphenylthiourea derivative, which, in turn, was used for further chemical transformations. The data of IR, 1 H NMR, mass spectra, and chemical analyses elucidated the structures of all newly synthesized heterocyclic compounds. Cytotoxicity, anti–HSV1 and anti–HAV, and MBB activities were evaluated for all newly synthesized heterocyclic compounds.

Convenient Synthesis of Some Thiadiazolotriazinones Carrying 4-Methylthiobenzyl Moieties as Possible Antimicrobial Agents

Abstract: 4-amino-6-(4-methylthiobenzyl)-3-mercapto-1,2,4-triazin-5(4H)-one was condensed with various substituted benzoic acids/aryloxyacetic acids in the presence of phosphorus oxychloride to afford a series of 7-(substituted aryl/aryloxymethyl)-3-(4-methylthiobenzyl)-4H-1,3,4-thiadiazolo[2,3-c]-1,2,4-triazin-4-ones in good yields. The structures of the newly synthesized compounds were confirmed on the basis of elemental analysis, IR, 1H NMR, and mass spectral studies. All the newly synthesized compounds were tested for their antibacterial and antifungal activity against a variety of microorganisms.

TiCl4-Catalyzed Efficient One-Pot Synthesis of α α-Amino Phosphonates

Abstract: α-Aminophosphonates are synthesized by three-component condensation of aldehydes, amines, and trimethylphosphite in acetonitrile by using TiCl4 as catalyst. Compared to conventional methods, this new method consistently has advantages, including excellent yields, short reaction times, and mild reaction conditions.

Part 7: Synthesis of Some New 1,5-Benzodiazepines Fused with Different Heterocyclic Moieties

Abstract: 3-cyano-1,11-dihydro-4,5-diphenyl-2-thioxopyrido[2,3-b](1,5)benzodiazepine 2 and 3-(2′-cyano-1′-phenyl-2′-ethanethiocarboxamide)-4-phenyl-1(H)(1,5)benzodiazepin2-one 3 were prepared via the reaction of 1,3-dihydro-4-phenyl-(1,5)benzodiazepin-2-one 1 with benzylidenecyanothioacetamide Compound 2 was treated with halo compounds to give the corresponding S-alkylated compounds 4 a−c, which underwent as intramolecular ring closure to thieno[3,25,6]pyrido[2,3-b](1,5)benzodiazepines 5 a−c under PTC conditions One-pot syntheis of compounds 5 a−c was achieved via the reaction of compound 2 with the appropriate halo compound under PTC conditions Compound 1 and 1-ethyl-4-phenyl-(1,5)benzodiazepin-2-one 9 were treated with carbon disulfide or phenylisothiocyanate and active nitriles to afford 4-thioxothiopyrano[4,3-b](1,5)benzodiazepines 8 and 10–14 Treatment of compound 10 with phenylisothiocyanate or acetic anhydride yielded oxazino-and pyrimido[4,5-b]thiopyrano-[4′,3′-b′](1,5)benzodiazepine 15 and 17 The rea

Synthesis, Reactions, and Antiviral Activity of 6′-Amino-2′-thioxo-1′,2′-dihydro-3,4′-bipyridine-3′,5′-dicarbonitrile

Abstract: Nicotinaldehyde 1 reacted with 2-cyanoethanethioamide 2to give 2-cyano-3-pyridin-3-ylprop-2-enethioamide 3, which reacted with a second mole of 2to give the corresponding 6′-amino-2′-thioxo-1′,2′-dihydro-3,4′-bipyridine-3′,5′-dicarbonitrile 6. The synthetic potentiality of compound 6 was investigated via its reaction with active halogen-containing reagents, e.g., chloroacetone, 2-chloro-3-oxobutanoate, 2-chloroacetamide, chloroaceto-nitrile, and ethyl chloroacetate, to afford the corresponding thieno[2,3-b]-pyridine derivatives. Structure elucidation of all newly synthesized heterocyclic compounds was based on the data of elemental analyses, and IR, 1 H NMR, as well as mass spectra. Cytotoxicity, anti–HSV1, anti–HAV, and MBB activities were evaluated for all newly synthesized heterocyclic compounds.

Silica Triflate as an Efficient Reagent for the Chemoselective Formylation of Alcohols

Abstract: Silica triflate, as a new and stable silica-based reagent, is prepared by a reaction of silica gel with trifluoromethane sulfonyl chloride at room temperature. This reagent can be used for the efficient and selective formylation of alcohols in the presence of phenols in a relatively short reaction time and high yields under heterogeneous reaction conditions.

Synthesis and Anti-Oxidant Activity of Novel Pyrimido[4,5-b]quinolin-4-one Derivatives With a New Ring System

Abstract: Reaction of 2-Hydrazino-derivative 6b with aliphatic acids yielded the triazolopyrido-pyrimidines 7a, b. Also, reaction of 6b with carbon disulfide or potassium thiocyanate afforded 10-mercapto/aminotriazolopyridopyrimidine (9,10), respectively. Compound 6b reacted with nitrous acid gave tetrazolopyridopyrimidine 11, the latter compound 11 reduced to 10-amino-derivative 12. Pyridopyrimidine derivatives 4b reacted with hydrazonoylchloride derivatives yielded triazolopyridopyrimidines 14a–c. Also, the reaction of 6b with aromatic aldehydes afforded the arylidines derivatives 16a–d, which were cyclized to triazolopyridopyrimidines deivatives 17a–d. Compound 6b reacted with α-haloketones to give triazines derivatives 18 with new ring systems. On the other hand, reaction of 6b with β-ketoesters afforded 10-pyrazolyl-pyridopyrimidines derivatives 19,20a–c, and 22. The latter compound was coupled with aldehydes and arylamine to give the derivatives 23,24, respectively. The antioxidant activity using ABTS reveale...

Synthesis, Spectral, and Antifungal Evaluation of Phosphorylated and Thiophosphorylated Benzothiazole Derivatives

Abstract: The phosphorylated and thiophosphorylated benzothiazole derivatives have been synthesized by the reaction of phosphorus oxychloride/phosphorus thiochloride with 2-(2′-aminophenyl)benzothiazole in 1:1, 2:1, 3:1, and 1:2 molar ratios in presence of triethylamine. Plausible structures have been proposed on the basis of elemental analysis IR, 1H NMR, 31P NMR, and mass spectral studies. The fungicidal activity of these derivatives have been evaluated against pathogenic fungi Aspergillus niger and Fusarium oxysporium. The fungicidal data reveals that these compounds are more fungitoxic than the parent 2-(2′-aminophenyl)benzothiazole compound.