Synthesis, Analgesic, and Antiparkinsonian Profiles of Some Pyridine, Pyrazoline, and Thiopyrimidine Derivatives

Summary. A series of substituted pyridine, pyrazoline, and thiopyrimidine derivatives were synthesized from 3-acetylpyridine, which was prepared from nicotinic acid as a naturally starting material. 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 assignment of the new compounds is based on chemical and spectroscopic evidence. The detailed synthesis, spectroscopic data, and pharmacological properties for synthesized compounds are reported.     

Straightforward synthesis,antiproliferative screening,and density functional theory study of some pyrazolylpyrimidine derivatives

Tetrahydropyrimidinone derivative was synthesized through one-pot three components condensation of 1,3-diphenylpyrazole-4-carbaldehyde with pentan-2,4-dione and urea under Biginelli reaction conditions. The corresponding chloro- and hydrazino derivatives were synthesized and utilized for the construction of some valuable N-heterocycles encompassing both pyrazole and pyrimidine cores, such as triazolopyrimidine, tetrazolopyrimidine, pyrazole, and pyrazolone derivatives through condensation with nitrogen nucleophiles and carbon electrophiles. The antiproliferative activity evaluation of the synthesized compounds against four human carcinoma cell lines namely, liver carcinoma (HepG2), breast adenocarcinoma (MCF7), prostate cancer (PC3), and colon cancer (HCT-116) cell lines revealed that some of them provided significant potency, as well as the density-functional theory (DFT) was studied. The permeability of various hydrophilic and hydrophobic synthesized compounds across both normal and cancer cells is confirmed via DFT simulation in which the much higher permeability through aquaporin channels revealed the selective cytotoxicity toward cancer cells.     

Design,Synthesis, In Vitro Antimicrobial,Antioxidant Evaluation,and Molecular Docking Study of Novel Benzimidazole and Benzoxazole Derivatives

A series of novel 2‐substituted benzimidazole and benzoxazole derivatives as a potential antimicrobial and antioxidant agent were synthesized via coupling of N‐methyl‐o‐phenylenediamine or 2‐amino‐phenol with aromatic aldehyde and acid in the presence of polyphosphoric acid as an efficient catalyst as well as solvent by conventional method in short reaction times with excellent yield. The newly synthesized benzimidazole and benzoxazole derivatives were evaluated for antimicrobial and antioxidant activity and exhibited excellent to good activities compared to the standard drugs. Furthermore, the theoretical predictions based on molecular docking against microbial DNA gyrase could provide an insight into the plausible mechanism of action and establish a link between the observed antimicrobial activity and the binding affinity shedding light on specific thermodynamic (bonded and nonbonded) interactions governing the activity. Furthermore, the synthesized compounds were analyzed for absorption, distribution, metabolism, and excretion properties and exhibited potential properties to build up as good oral drug candidates.     

Design,Synthesis, and Antimicrobial Evaluation of Novel Thienopyrimidines and Triazolothienopyrimidines

2-Cyanoacetohydrazide and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene derivatives were exploited as starting materials for the syntheses of novel thienopyrimidines and triazolothienopyrimidines. The proclivity of these compounds toward one-carbon donor reagents such as carbon disulfide, phenyl isothiocyanate, and aromatic aldehydes was investigated. The structures of all synthesized compounds were ascertained by spectral and analytical data. The antimicrobial activity of the target synthesized compounds was tested against various microorganisms.     

Synthesis,Characterization, and Biological Evaluation of 10H‐Phenothiazines,Their Sulfones and Ribofuranosides

10H‐phenothiazines are synthesized via Smiles rearrangement. These prepared phenothiazines act as a base to prepare ribofuranosides by treating them with b‐D ‐ribofuranosyl‐1‐acetate‐2,3,5‐tribenzoate. 10H‐phenothiazines on refluxing with hydrogen peroxide in glacial acetic acid gave 10H‐phenothiazine‐5,5‐dioxides. The synthesized compounds were evaluated for their antioxidative properties through in vitro studies, and they are also screened for their antimicrobial activity. The structure of the synthesized compounds has been established by elemental analysis and spectroscopic data.     

Synthesis,Spectral, and Coordination Properties of Halogen-Substituted Tetraarylporphyrins

2,3,7,8,12,13,17,18-Ocatbromo-5,10,15,20-tetra-(4-chloroprienyl)porphyrin and 2,3,7,8,12,13,17,18-octachloro-5,10,15,20-tetra-(4-bromophenyl)porphyrin have been synthesized. The obtained compounds have been identified by electronic absorption and ¹H NMR spectroscopy as well as mass spectrometry. The complex-forming properties of the synthesized porphyrins in the zinc acetate (II)-acetonitrile system at 278–298 K have been studied. Kinetic parameters of the formation of the corresponding zinc complexes in acetonitrile have been determined.

     

Amphiphilic poly-n-vinyl-2-pyrrolidone: Synthesis,properties, nanoparticles

Water-soluble amphiphilic polymers based on N-vinyl-2-pyrrolidone (Amph-PVP) have been synthesized. Amphiphilic diblock polymers have been obtained via a single-step technique. For the synthesized amphiphilic polymers, the critical concentrations of mycelium formation (CCM) have been determined. The structure of the polymers obtained was confirmed by IR and NMR spectroscopy. The critical concentration of micelle formation (CCM) for the synthesized polymers has been found to be in the micromolar range. The fluorescent dye 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (Dil) was chosen as a model substance for the synthesis of nanoparticles. Micellar particles were obtained via an ultrasonic technique followed by evaporation of the organic solvent (emulsion method).     

一种低代超支化聚醚的合成、表征及表面活性研究

以十二胺、丙烯酸甲酯和乙二胺为原料,甲醇为溶剂,采用发散合成法合成一种低代超支化分子骨架.采用1H NMR对分子骨架的结构进行了表征.在此基础上,以低代骨架为起始剂,分别与环氧乙烷、环氧丙烷加成制备了一种超支化聚醚,测定了它的表面张力、浊点,同时计算出了它的HLB值.结果表明:骨架的分子结构与所设计的结构相符,合成的聚醚具有典型表面活性剂的性质.     

Synthesis, characterization, and antimicrobial evaluation of oxadiazole congeners

A series of 1,3-oxazole, 1,3-thiazole, isomeric 1,2,4-oxadiazole, 1,3,4-oxadiazole, and 1,2,3,4-tetrazole heterocycles was synthesized. All the compounds shared as a common feature the presence of a 4-hydroxyphenyl substituent. The structures of the synthesized compounds were confirmed by MS, 1H-NMR, and elemental analysis. In vitro antimicrobial activity for all the newly synthesized compounds at concentrations of 200-25 μg/mL was evaluated against Gram+ve organisms such as methicillin-resistant Staphylococcus aureus (MRSA), Gram-ve organisms such as Escherichia coli (E. coli), and the fungal strain Aspergillus niger (A. niger) by the cup plate method. Ofloxacin and ketoconazole (10 μg/mL) were used as reference standards for antibacterial and antifungal activity, respectively. Compounds 15, 16, and 20 showed notable antibacterial and antifungal activities at higher concentrations (200 μg/mL), whereas 17-19 were found to display significant antibacterial or antifungal activity (25-50 μg/mL) against the Gram+ve, Gram-ve bacteria, or fungal cells used in the present study.     

Synthesis,Structure, Photophysical Properties,and Photostability of Benzodipyrenes

This work explores the syntheses, structures, photophysical properties, and photostability of benzodipyrenes (BDPs). BDPs were synthesized through an InCl₃-AgNTf₂-catalyzed, four-fold alkyne benzannulation reaction. The structures of BDP 4 a and its corresponding endoperoxide product were unambiguously confirmed by X-ray crystallography. The BDPs reported here can also be recognized as peri- and cata-benzannulated pentacenes with a non-functionalized central ring. Unlike the previous reported pentacene-based polycyclic aromatic hydrocarbons, the absorbances of the BDPs were blueshifted by ca. 40 nm relative to pentacene, even after extension of π-conjugation. The newly synthesized BDP products exhibit relatively good stability with half-lives as high as 4612 min in THF.     

Sulfation of deoxynivalenol,its acetylated derivatives,and T2-toxin

The synthesis of several sulfates of trichothecene mycotoxins is presented. Deoxynivalenol (DON) and its acetylated derivatives were synthesized from 3-acetyldeoxynivalenol (3ADON) and used as substrate for sulfation in order to reach a series of five different DON-based sulfates as well as T2-toxin-3-sulfate. These substances are suspected to be formed during phase-II metabolism in plants and humans. The sulfation was performed using a sulfuryl imidazolium salt, which was synthesized prior to use. All protected intermediates and final products were characterized via NMR and will serve as reference materials for further investigations in the fields of toxicology and bioanalytics of mycotoxins.     

Hydrazyl,Nitronyl-, and imino-nitroxides: Synthesis,properties and reaction with nitric oxide and nitrogen dioxide

Ten novel and stable free radicals of nitronyl-, imino-nitroxide and hydrazyl type compounds were synthesized and their physico-chemical properties investigated. UV-Vis and ESR spectroscopic data, as well as the lipophilicities and specific hydrophobic areas of the compounds are compiled. The reaction of these radical compounds with nitric oxide and nitrogen dioxide was also investigated. The radicals synthesized, show selectivity in their reaction with these nitric oxides, depending on their structure (nitronyl-nitroxide radicals react with NO, while hydrazyl radicals react with NO₂). The processes are easily monitored by UV-Vis or ESR spectroscopy.     

Synthesis and Antioxidant Evaluation of Some Novel Thiophene,Pyrazole, Chromene,Pyrazolotriazine Derivatives Bearing Sulfonamide Moiety

As a part of ongoing studies in developing new potent antioxidant agents, N‐[4‐(aminosulfonyl)phenyl]‐2‐cyanoacetamide ( 3 ) was utilized as key intermediate for the synthesis of some new thiophene, chromene, and pyrazolotriazine pyridine derivatives. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, ¹H‐NMR, and mass spectral data. Representative compounds of the synthesized products were tested and evaluated as antioxidant. Compounds 7 and 30 are promising compounds.     

Design,synthesis, characterization,photophysical and pH chemosensor studies of novel 2,4,6-trisubstituted pyridines

For the application in organic electronics as well as pH meters, a series of novel 2,4,6-trisubstituted pyridines have been synthesized by the reaction of substituted aromatic aldehydes and substituted 3-acetylcoumarin with ammonium acetate. The structures of all the new compounds were characterized by IR, NMR, and GC–MS analysis. The important photo physical prerequisites for organoelectronic such as optical absorption and thermal stability were determined for the synthesized molecules. Optical properties were studied by UV–visible absorption and fluorescence spectroscopy. Optical band gaps of the 2,4,6-trisubstituted pyridines were found to be around 3.01–3.06?eV as calculated from their onset absorption edge. The pH-dependent changes in the fluorescence intensity suggest that 2,4,6-trisubstituted pyridines are useful applicants in intracellular pH meters.     

Iron Oxide Nanoparticles: Biosynthesis,Magnetic Behavior,Cytotoxic Effect

Iron oxide nanoparticles have attracted much attention because of their superparamagnetic properties and their potential applications in many fields such as magnetic storage devices, catalysis, sensors, superparamagnetic relaxometry (SPMR), and high-sensitivity biomolecule magnetic resonance imaging (MRI) for medical diagnosis and therapeutics. In this study, iron oxide nanoparticles (Fe₂O₃ NPs) have been synthesized using a taranjabin (camelthorn or persian manna) aqueous solution. The synthesized Fe₂O₃ NPs were identified through powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), field energy scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX), vibrating-sample magnetometer (VSM) and Raman technics. The results show that the nanoparticles have a hexagonal structure with 20 to 60 nm in size. The cytotoxic effect of the synthesized nanoparticles has been tested upon application against lung cancer cell (A549) lines. It was found that there is no cytotoxic activity at lower concentrations of 200 μg/mL. The ability of the synthesized nanoparticles for lead removal in wastewaters was tested. Results show that highest concentration of adsorbent (50 mg/L) has maximum removal efficiency (96.73 %). So, synthesized Fe₂O₃ NPs can be a good candidate to use as heavy metals cleaner from contaminated waters.     

New Unsymmetrically Substituted Benzothiadiazole-Based Luminophores: Synthesis,Optical, Electrochemical Studies,Charge Transport,and Electroluminescent Characteristics

Three new benzothiadiazole (BTD)-containing luminophores with different configurations of aryl linkers have been prepared via Pd-catalyzed cross-coupling Suzuki and Buchwald–Hartwig reactions. Photophysical and electroluminescent properties of the compounds were investigated to estimate their potential for optoelectronic applications. All synthesized structures have sufficiently high quantum yields in film. The BTD with aryl bridged carbazole unit demonstrated the highest electrons and holes mobility in a series. OLED with light-emitting layer (EML) based on this compound exhibited the highest brightness, as well as current and luminous efficiency. The synthesized compounds are not only luminophores with a high photoluminescence quantum yield, but also active transport centers for charge carriers in EML of OLED devices.     

Partial synthesis of aromatic carotenoids,tedanin, agelaxanthin a,tethyatene, and renieratene

Aromatic carotenoids, tedanin, agelaxanthin A, and tethyatene were synthesized from 0- acetyl-6-citraurin derived from natural zeaxanthin, and tethyatene was further transformed into renieratene as the first example of aromatization of an alicyclic ring in carotenoids.     

Novel 1,4-benzothiazine derivatives: synthesis,crystal structure,and anti-bacterial properties

In order to develop relatively small molecules as pharmacologically active molecules, novel 1,4-benzothiazine derivatives with triazole and oxazolidinone were synthesized. In this study, a series of 1,2,3-triazolylmethyl-1,4-benzothiazine derivatives were developed by exploiting a click chemistry reaction using a CuI-catalyzed Huisgen [3 + 2] cycloaddition. Starting from 2-(substituted)-3,4-dihydro-2H-1,4-benzothiazi-3-one, a number of 1,4-benzothiazine derivatives were also synthesized using different alkylating agents to give a 4-(substituted)-2-(substituted)-3,4-dihydro-2H-1,4-benzothiazi-3-one in good yields. The crystal and molecular structure of compound oxazolidin-2-one in basic benzothiazine was established by single-crystal X-ray diffraction. The newly synthesized products were subjected to in vitro biological evaluation. The result indicated that the compounds show convincing antibacterial activities against different microorganisms. All structures of the synthesized compounds were elucidated on the basis of spectral analyses and chemical reactions.     

Novel selective synthesis of α-chloromethyl, α,α-dichloromethyl,and α,α,α-trichloromethyl ketones from aldehyde utilizing electroreduction as key reactions

A variety of α-chloromethyl, α,α-dichloromethyl, and α,α,α-trichloromethyl ketones were synthesized from aldehyde utilizing cathodic reduction as key reactions.     

Pyrenes,Peropyrenes, and Teropyrenes: Synthesis,Structures, and Photophysical Properties

The design of a relatively simple and efficient method to extend the π‐conjugation of readily available aromatics in one‐dimension is of significant value. In this paper, pyrenes, peropyrenes, and teropyrenes were synthesized through a double or quadruple benzannulation reaction of alkynes promoted by Brønsted acid. This novel method does not involve cyclodehydrogenation (oxidative aryl–aryl coupling) to arrive at the newly incorporated large arene moieties. All of the target compounds were synthesized in moderate to good yields and were fully characterized with the structures unambiguously confirmed by X‐ray crystallography. As expected, photophysical characterization clearly shows increasing red‐shifts as a function of extended conjugation within the fused ring systems.