Synthesis,Reactions, and Pharmacological Activities of Some Pyrimidines Using (<Emphasis Type="Italic">N</Emphasis>-Methylindolyl)acetic Acid as Synthon

Summary. A series of pyrimidinones, thienopyrimidines, and their derivatives were synthesized using N-methylindolyl acetic acid as a starting material. Sixteen new heterocyclics containing a pyrimidine ring were thus prepared. The pharmacological screening showed that many of these compounds have good analgesic and antiparkinsonian activities comparable to Voltarene^? and Benzatropine^? as reference drugs. The structure assignments of the new compounds based on chemical and spectroscopic evidence. The detailed synthesis, spectroscopic data, and pharmacological properties are reported.     

Synthesis and Some Pharmacological Studies of New Benzenesulfonamide Derivatives

Summary.  New benzenesulfonamide derivatives containing pyrazole and oxadiazole moieties were prepared starting from sodium saccharin. The structures of the novel compounds were characterized by elemental analyses and spectroscopic methods. The new compounds are structurally related to the COX-2 inhibitor celecoxib (Celebrex^?). A pharmacological study of the pyrazoles revealed that several compounds possess higher analgesic and antiinflammatory activities than celecoxib, particularly 11 and 17. Most of the pyrazoles showed a significant increase in the sleeping time of thiopentone anaesthesized mice and also protected mice against the convulsive and lethal effects of pentylenetetrazole. Moreover, the ulcerogenic activity of those compounds showing a pronounced antiinflammatory effect was also studied. Received August 20, 2001. Accepted (revised) November 19, 2001     

Synthesis,characterization and pharmacological investigations of some novel heterocyclic derivatives incorporating pyrene and sugar moieties

A series of substituted pyrene derivatives 2–15 incorporated heterocyclic and sugar moieties were synthesized and evaluated as antiviral activities using 1-acetylpyrene as a starting material. The structure assignment of the new compounds was based on chemical and spectroscopic evidence. The detailed synthesis, spectroscopic data and pharmacological activities of the synthesized compounds were reported.     

Preparation of Pseudohalidoheptasulfur(+1) Hexafluorometallates S7X+MF−6 (X = CN,OCN, SeCN; M = As,Sb)

The preparation and spectroscopic characterization of S₇X⁺MF^?₆ (X = CN, OCN, SCN, SeCN; M = As, Sb) is reported. The new compounds are formed in analogy to the preparation of halidocycloheptrasulfur(+1) cations from S²⁺₈(MF^?₆)₂ and alkali pseudohalides in So₂ as solvent. Their thermal stabilities decrease with the increasing Pearson hardness of the pseudohalide ligands.     

Triazole‐Substituted Nitroarene Derivatives: Synthesis,Characterization, and Energetic Studies

A series of dense and energetic polynitroaryl‐1,2,4‐triazoles were synthesized through the nitration of aryl‐1,2,4‐triazoles. The Cu‐catalyzed/base‐mediated coupling reactions of haloarenes with 1,2,4‐triazoles delivered N‐aryl‐1,2,4‐triazoles. These new nitro‐rich‐aryltriazoles were characterized by analytical and spectroscopic methods. The solid‐state structures of most of these compounds were established by X‐ray diffraction analysis. Their thermal properties were determined by differential scanning calorimetry–thermogravimetric analysis. Their heats of formation (HOFs) and crystal densities were also calculated. The densities of the synthesized compounds ranged from 1.40 to 1.85 g cm^?3. Some of these newly synthesized compounds exhibited high positive HOFs, good thermal stabilities, high densities, and reasonable detonation velocities and pressures.     

Synthesis and characterization of copper(II) complexes incorporating pyrazolyl-derived N,S-donor bidentate ligands

The novel bidentate N,S-donor anionic ligands [PhNCSIndz]^?, [PhNCSImz]^?, [PhNCSPz^Me3]^?, and [EtNCSPz]^?, where Indz?=?indazole, Imz?=?imidazole, Pz^Me3?=?3,4,5-trimethylpyrazole, and Pz?=?pyrazole, were synthesized and used to prepare Cu(II) complexes of general formula [Cu(N^S)₂]. The ligands were synthesized via direct addition of phenylisothiocyanate or ethylisothiocyanate into THF suspensions of the corresponding sodium-pyrazolate salts. All of the synthesized compounds, including the ligands and the complexes, were characterized by physico-chemical and spectroscopic methods, and crystal structures of [Cu(EtNCSPz)₂] and [Cu(PhNCSPz^Me2)₂] were determined by X-ray diffraction analysis, showing a trans-square planar geometry for [Cu(EtNCSPz)₂] and a distorted tetrahedral geometry for [Cu(PhNCSPz^Me2)₂].     

Synthesis, Reactions, and Anti-inflammatory Activity of Heterocyclic Systems Fused to a Thiophene Moiety Using Citrazinic Acid As Synthon

Summary. A series of pyridines, pyrimidinones, and oxazinones were synthesized as anti-inflammatory agents using citrazinic acid (2,6-dihydroxyisonicotinic acid) as a starting material. Acryloyl pyridine was treated with cyanothioacetamide to give cyano pyridine-thione, which was reacted with ethyl chloroacetate to yield the corresponding amino ester. The ester was hydrolysed to the sodium salt, which was treated with acetic anhydride to afford 2-methyloxazinone, which was treated with ammonium acetate to afford 2-methylpyrimidinone followed by methylation with methyl iodide to yield 2,3-dimethylpyrimidinone. In addition, the oxazinone derivative was reacted with aniline or hydrazine hydrate to give 3-phenyl- or 3-aminopyrimidinones. The latter reacted with thiophene-2-carboxaldehyde or phenylisothiocyanate to afford Schiff’s bases or thiosemicarbazides. 3-Aminopyrimidinone was treated with phthalic anhydride or 1,2,4,5-benzenetetracarboxylic acid dianhydride or toluene-3,5-diisocyanate to afford the corresponding imide, bis-imide, and bis-semicarbazide derivatives. The pharmacological screening showed that many of these compounds have good anti-inflammatory activity comparable to Prednisolone^? as reference drug.     

Reaction of K[(π-C5H5)Fe(CO)(CN)2] with boranes and AlCl3: Preparation and investigation of iron(II) complexes containing isocyanoborate ligands

Iron(II) complexes containing CNBX^?₃ or CNBX₂NC^? ligands were prepared from the reaction of K[(π-C₅H₅)Fe(CO)(CN)₂] with boranes (BX₃; X = F, Cl, Br H, Ph). Stable, twelve-membered ring compounds containing Fe, C, N, and B atoms were formed involving CNBF₂NC^? and CNBBr₂NC^? ligands. The reaction of K[(π-C₅H₅)Fe(CO)(CN)₂] with AlCl₃ gave a four-center complex with two Fe and two Al atoms. The compounds were studied by infrared and mass spectroscopic methods.     

Preparation,structure elucidation,and antioxidant activity of new bis(thiosemicarbazone) derivatives

Schiff-base–bearing new bis(thiosemicarbazone) derivatives were prepared from terephthalaldehyde and various thiosemicarbazides. FT–IR, ¹H NMR, ¹³C NMR, and UV–Vis spectroscopic methods and elemental analysis were used to elucidate the identification of the synthesized molecules. The in vitro antioxidant activity of the synthesized compounds was analysed with the 1,1-diphenyl-2-picryl hydrazyl free-radical–trapping process. The synthesized compounds exhibited lower antioxidant activity than the standard ascorbic acid. IC₅₀ values of the synthesized molecules measured from 3.81 ± 0.01 to 29.05 ± 0.11 μM. Among the synthesized compounds, compound 3 had the best antioxidant activity. Moreover, this study explained the structure–activity relationship of the synthesized molecules with different substituents in radical trapping reactions.     

Synthesis of Amino,Azido, Nitro,and Nitrogen‐Rich Azole‐Substituted Derivatives of 1H‐Benzotriazole for High‐Energy Materials Applications

The amino, azido, nitro, and nitrogen‐rich azole substituted derivatives of 1H‐benzotriazole have been synthesized for energetic material applications. The synthesized compounds were fully characterized by ¹H and ¹³C NMR spectroscopy, IR, MS, and elemental analysis. 5‐Chloro‐4‐nitro‐1H‐benzo[1,2,3]triazole ( 2 ) and 5‐azido‐4,6‐dinitro‐1H‐benzo[1,2,3]triazole ( 7 ) crystallize in the Pca2₁ (orthorhombic) and P2₁/c (monoclinic) space group, respectively, as determined by single‐crystal X‐ray diffraction. Their densities are 1.71 and 1.77 g cm^?3, respectively. The calculated densities of the other compounds range between 1.61 and 1.98 g cm^?3. The detonation velocity (D) values calculated for these synthesized compounds range from 5.45 to 8.06 km s^?1, and the detonation pressure (P) ranges from 12.35 to 28 GPa.     

Keggin-type cesium salt of first series transition metal-substituted phosphomolybdates: one-pot easy synthesis,structural, and spectral analysis

The Keggin-type cesium salt of transition metal-substituted phosphomolybdates, Cs₅[PCo(H₂O)Mo₁₁O₃₉]?·?6H₂O (1) and Cs₅[PMn(H₂O)Mo₁₁O₃₉]?·?6H₂O (2), were synthesized from commercially available H₃PMo₁₂O₄₀. The compounds were characterized by thermal, structural, and spectroscopic techniques. X-ray structural analysis reveals that, in these isostructural disordered compounds, the transition metal (Co/Mn) and Mo atoms are distributed over 12 positions. The presence of Co/Mn atoms was confirmed by powder XRD, FT-IR, DR-UV-Vis, ESR, and ³¹P NMR studies.     

A new family of heavy transition metal coordination compounds and its application,I. Design,synthesis and characterization of volatile organohafnium precursors

The first three representatives of a new family of volatile organohafnium compounds suitable as metallo-organic chemical vapour deposition precursors were synthesized. A combination of cyclopentadienyl and alkoxo-ligands with a bicyclo[2.2.1]heptanc framework was used. Volatility at relatively low temperatures for hafnium compounds was found and the precursors were characterized by elemental analysis and spectroscopic methods (IR, ¹H and ¹³C NMR, mass spectrometry and mass-analysed ion kinetic energy spectroscopy). The outlook for use in hafnium functional materials synthesis was derived from the fragmentation data.     

Synthesis,spectral characterization and antitumor activity of phenothiazine derivatives

Different types of phenothiazine derivatives were synthesized by reactions of 10-alkyl-10H-phenothiazine-3-carbaldehydes. Structures of the prepared compounds were confirmed through spectroscopic techniques such as IR, ¹H NMR, ¹³C NMR and mass spectroscopy. All the compounds were studied for their antitumor activities.     

Design,synthesis and cytotoxic activity of vitamin E bearing selenium compounds against human breast cancer cell line (MCF-7)

A new series of vitamin E/selenated pyridine, vitamin E/selenated pyridazine, vitamin E/selenated coumarine and vitamin E/selenated nicotine moieties were synthesized and their cytotoxic activity is investigated using the human breast cancer cell line. The newly synthesized compounds were characterized using spectroscopic tools (IR, ¹H NMR, ¹³C NMR, and mass spectroscopy) as well as microanalysis. Our study reveals that compound vitamin E/selenated nicotine moiety has the highest cytotoxic effect than the other synthesized compounds.     

Synthesis,Characterization, and Antimicrobial Properties of New 1,3,4‐Thiadiazoles Derived from Azo Dyes

Some new 1,3,4‐thiadiazoles derived from azo dyes were synthesized. Two different synthesis methods were used for these compounds: Esters pertaining to the azo dyes were converted into 1,3,4‐thiadiazoles, or benzothiazole ester derivatives were converted to 1,3,4‐thiadiazoles followed by the synthesis of azo dye derivatives. The desired products were successfully obtained using the latter method. The molecular structures of these compounds were characterized using spectroscopic methods such as FTIR, ¹H NMR, ¹³C NMR, and elemental analysis. Furthermore, antimicrobial activity was studied for the synthesized compounds. Compound 3e exhibited antimicrobial activity against three different microorganisms. Compounds 3a , 3b , and 3d had activity against two different microorganisms, while compound 3c showed activity against only one microorganism.     

Esr studies on the reactive character of the radical anions,so−2, so−3 and so−4 in aqueous solution

The reactive characteristics of the oxy anion radicals of sulphur, SO^?₂, SO^?₃ and SO^?₄ were investigated by use of the rapid-mixing flow technique coupled with electron spin resonance (ESR) which can detect the radicals having a lifetime of 5–100 msec. The SO^?₂ reduced the aromatic nitro compounds to the corresponding anion radicals, but did not abstract the hydrogen from the saturated compounds nor add to the unsaturated compounds. The SO^?₃ could add to the compounds having CC bond, but did not abstract the hydrogen from the saturated compounds nor reduce the aromatic nitro compounds. The SO^?₄ could abstract the hydrogen from the saturated compounds and also add to the unsaturated compounds having CC bond, but did not reduce the aromatic nitro compounds. These differences of the reactivity towards the organic substrates were discussed on the basis of the difference in the distribution of the unpaired electron density of each radical anion.     

N‐Heterocyclic Carbene Formation Induced Fluorescent and Colorimetric Sensing of Fluoride Using Perimidinium Derivatives

In this study, two perimidinium derivatives ( 1 and 2 ) were designed, synthesized, and developed as efficient fluorescent and colorimetric chemodosisensors for F^? in DMSO or more competitive media (DMSO containing 10 % water). In the presence of F^?, the yellow and non‐fluorescent solution of 1/2 became colourless and exhibited strong blue fluorescence. This unique spectroscopic behaviour of 1/2 towards F^? was attributed to the formation of N‐heterocyclic carbene deprotonated by F^?, which immediately reacted with water to give a colourless and fluorescent carbinol. Interestingly, it was found that this carbinol intermediate was unstable and further underwent a redox disproportionation to generate two other optically changed compounds. All the proposed mechanisms for the sensing process have been carefully confirmed by experiments.     

Synthesis,characterization, and photophysical properties of paraben substituted cyclotriphosphazenes with hydrophilic side groups

Abstract

In this study, five new paraben substituted cyclotriphosphazene compounds containing hydrophilic glycol groups were successfully synthesized. All synthesized cyclotriphosphazene compounds 1-10 were fully characterized via general spectroscopic techniques such as ¹H, ³¹P NMR and MALDI-TOF mass spectrometry. In addition, the investigations of the UV-vis absorption and fluorescence emission properties of the 1-10 carried out via absorption and fluorescence spectroscopies in different solvents. The absorbance bands of the all synthesized compounds 1-10 were observed at about 230–300?nm in all solvents studied. Furthermore, the highest fluorescence emission intensity of the compounds 1-10 was observed in tetrahydrofuran at about 312?nm and the lowest emission intensity was observed in chloroform. The synthesized molecules can be used as custom designed molecules to investigate the DNA binding properties in automatic biosensor device in our laboratories, since they carry hydrophilic glycol units for water solubility and paraben derivatives for DNA effecting properties.     

Synthesis, Reactions, and Pharmacological Screening of Heterocyclic Derivatives Using Nicotinic Acid as a Natural Synthon

Summary. A series of substituted pyridine derivatives were prepared from 3-acetylpyridine, which was prepared from the corresponding nicotinic acid as a natural starting material. Reaction of 3-acetylpyridine with indole-3-carboxaldehyde afforded the corresponding 3-β-(3-indolyl)acryloylpyridine, which was reacted with hydroxylamine hydrochloride in pyridine or acetic acid in the presence of sodium acetate to afford 3-β-(3-indolyl)acryloylpyridine oxime and oxazole derivatives. The oxime was treated with ethyl isothiocyanate or toluene-3,5-diisocyanate in refluxing dioxane to give the corresponding ethyl thiosemicarbazide and 3,5-bissemicarbazide derivative. 3-β-(3-Indolyl)acryloylpyridine was condensed with malononitrile in refluxing ethanol in the presence of piperidine as a catalyst to give cyanoaminopyrane, while it was condensed with ethyl cyanoacetate or malononitrile in the presence of ammonium acetate to yield cyanopyridone and cyanoaminopyridine derivatives. Cyclization of acryloylpyridine with o-phenylenediamine in refluxing butanol led to the formation of the corresponding benzodiazipine via the intermediate A. Finally, cycloaddition reaction of acryloylpyridine with thiourea yielded thioxopyrimidine, which was treated with chloroacetic acid to yield thiazolopyrimidine. An arylmethylene derivative was prepared by reacting thiazolopyrimidine with indole-3-carboxaldehyde or by reacting thioxopyrimidine with indole-3-carboxaldehyde and chloroacetic acid in one step. The pharmacological screening showed that many of these obtained compounds have good analgesic and anticonvulsant activities comparable to Valdecoxib^? and Carbamazepine^? as reference drugs.     

Novel Cyclic Sulfonium‐Based Ionic Liquids: Synthesis,Characterization, and Physicochemical Properties

A new series of ionic liquids composed of three cyclic sulfonium cations and four anions has been synthesized and characterized. Their physicochemical properties, including their spectroscopic characteristics, ion cluster behavior, surface properties, phase transitions, thermal stability, density, viscosity, refractive index, tribological properties, ion conductivity, and electrochemical window have been comprehensively studied. Eight of these salts are liquids at room temperature, at which some salts based on [NO₃]^? and [NTf₂]^? ions exhibit organic plastic crystal behaviors, and all the saccharin‐based salts display relatively high refractive indices (1.442–1.594). In addition, some ionic liquids with the [NTf₂]^? ion exhibit peculiar spectroscopic characteristics in FTIR and UV/Vis regions, whilst those salts based on the [DCA]^? ion show lower viscosities (34.2–62.6 mPa s at 20 °C) and much higher conductivities (7.6–17.6 mS cm^?1 at 20 °C) than most traditional 1,3‐dialkylimidazolium salts.