Synthesis and properties of new derivatives of 4h-1,2,4-oxadiazin-5(6H)-one

In this research, multicomponent reactions of cefixime, isothiocyanates, and alkyl bromides were carried out for the synthesis of new iminothiazole derivatives with high yields in water as the solvent at room temperature in the presence of catalytic amounts of Cu@KF/CP NPs as catalysts. Also, the ability of Cu@KF/Clinoptilolite nanoparticles (NPs) to adsorb and remove 4-NP and cefixime from water was investigated. The Cu@KF/Clinoptilolite nanoparticles were synthesized by employing a water extract of Petasites hybridus rhizomes. For this experiment, all of the components obtained from Fluka and Merck were subjected to further purification. The antibiotic used in this investigation, cefixime, was obtained from a pharmaceutical facility situated in Sari, Mazandaran, Iran. The antibiotic factory is located in Sari City, Iran. All solutions were prepared using distilled water. The shape of Cu@KF/CP nanoparticles was analyzed using images obtained from a Holland Philips XL30 scanning electron microscope. An analysis was performed on the crystalline structure of Cu@KF/CP nanoparticles (NPs), and a room temperature X-ray diffraction (XRD) examination was carried out utilizing a Holland Philips Xpert X-ray powder diffractometer. The X-ray diffraction (XRD) examination was conducted using CuK radiation, which has a wavelength of 0.15406 nm. The analysis covered a 2ε angle range from 20 to 80°. The nanostructures that were produced were chemically analyzed using X-ray energy dispersive spectroscopy (EDS) with an S3700N equipment. The morphology and dimensions of Cu@KF/CP nanoparticles were characterized using a Philips EM208 transmission electron microscope operated at an acceleration voltage of 90 kV. The primary objective of this study was to develop a sustainable approach for producing new iminothiazole derivatives 4. This was achieved using a highly efficient three-component reaction combining cefixime 1, isothiocyanates 2, and alkyl bromides 3. The reaction was carried out in water at ambient temperature, using Cu@KF/CP NPs as a highly effective catalyst, leading to excellent yields. Moreover, the study findings showed that the synthesized compounds demonstrated a significant antioxidant activity compared to conventional antioxidants. The antibacterial efficacy of the synthesized compounds was evaluated against both Gram-positive and Gram-negative bacteria. Furthermore, Cu@KF/CP nanoparticles were utilized to adsorb CFX and 4-NP from water-based solutions. This study showcases the effective synthesis of innovative iminothiazole derivatives through the use of multicomponent reactions, involving the combination of cefixime, isothiocyanates, and alkyl bromides. The reactions were conducted in a water-based solvent. The reactions were carried out at room temperature, utilizing Cu@KF/CP NPs as catalysts. The Cu@KF/CP nanoparticles, a newly developed heterogeneous nanocatalyst, were synthesized and evaluated utilizing X-ray diffraction (XRD), fieldemission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) research techniques. Cu@KF/CP nanoparticles are utilized to adsorb CFX and 4-NP from water-based solutions. The objects were manufactured using a straightforward and uncomplicated approach. The BET surface area of Cu@KF/CP NPs was measured to be 201.8 m2/g. The experimental equilibrium data was evaluated by applying the isotherms of the Langmuir, Freundlich, Dubinin-Radushkevich, and Redlich-Peterson models. Additionally, we examined the catalytic efficiency of Cu@KF/CP nanoparticles (NPs) in reducing various colors in water.

Urazolium diacetate catalyzed synthesis of new derivatives of 1,3-thiazolidine-4-ones (azo dispersive dyes family) via multicomponent reaction of various aldehydes, thioglycolic acid and 4-aminoazobenzene under solvent-free reaction was reported. This avenue for the synthesis of new derivatives of thiazolidine-4-one has advantages as: short reaction times, high yields, green aspect of chemistry and environmental friendliness, easy workup, solvent-free conditions and convenient operation.

Derivatives of 1,2,4-triazole is a very perspective class of heterocyclic compounds which have high therapeutic effectiveness. The main direction of research on these derivatives are antifungal, antiviral, antibacterial, soothing, hypnotic, anticonvulsant, anti-inflammatory and other activities.
 The aim was to analyze literature data and generalize recent advances in the study of antimicrobial and antifungal action of 1,2,4-triazole derivatives which can help to create new biologically active substances of this type of activity. Bibliosemantical method, systems thinking and the results of our own research were used in the work.
 The results of the literature review of antimicrobial and antifungal activity among new alkyl, aryl and heteryl derivatives of 1,2,4-triazole and among complex compounds, which contain 1,2,4-triazole are as ligands were analyzed and systematized. Some dependence of this type of activity on specialty of chemical structure of heterocyclic system derivatives was specified.
 Perspective of purposeful synthesis of new derivatives of 1,2,4-triazole and products of their transformation as available object for studying biological activity and expanding knowledge about antimicrobial and antifungal activity of this class of heterocyclic compounds were shown with informational analysis. Topicality and practical importance of finding biologically active compounds and receiving biologically active substance by synthesis of new derivatives of 1,2,4-triazole with high antimicrobial activity in relation to gram-negative and gram-positive bacteria were demonstrated.

Background: Thiazolidinone-4-ones belong to an important heterocyclic compounds because of their broad spectrum of biological activities. Several methods for the synthesis of 4-thiazolidinones were reported in the literature. The main synthetic routes to synthesize 1,3-thiazolidin-4-ones is the three component reaction between amine, a carbonyl compound and a mercapto-acid. Objective: Dapsone-Cu supported on silica coated Fe3O4 (Fe3O4@SiO2-pr@dapsone-Cu) as a new heterogeneous nanoparticle catalyst was synthesized and the structure and morphology of this catalyst were characterized by Fourier transform infrared spectroscopy (FT-IR), Xray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), zeta potential, vibrating sample magnetometry (VSM) and thermal gravimetric analysis (TGA). The new synthesized catalyst was applied as an effective nanocatalyst for the synthesis of new derivatives of azo-linked thiazolidinones through one-pot multi-component reaction of various aromatic aldehydes, thioglycolic acid and 4-aminoazobenzene under solvent-free condition. Methods: A mixture of aldehyde, thioglycolic acid, 4-aminoazobenzene (1 mmol) and 0.05 g Fe3O4@SiO2@dapsone-Cu MNPs were stirred at room temperature under solvent-free condition. Results: We report a facile, green, new and efficient method for the synthesis of thiazolidine-4-ones through three component reaction of various aldehydes, thioglycolic acid and 4-aminoazobenzene in the presence of Fe3O4@SiO2-propyl@dapsone-Cu complex under solvent-free reaction. Conclusion: This new procedure has the notable advantages such as excellent yields, short reaction time, operational simplicity, easy work-up, eco-friendly and using a non-toxic catalyst. Also, the catalyst is easily recoverable in the presence of an enourmous magnet and reused for six consecutive reaction cycles without significant loss of activity.

A novel photocatalyzed trifluoromethylthio-trifluoromethylation of alkenes has been developed, using CF3SO2Na as both CF3 and SCF3 source. This photocatalyzed dual-oxidative strategy, which combine...

The synthesis of new derivatives 2 of α-hydrazino-(disubstituted)- alkylphosphonic acids by the Lewis acid mediated addition of dialkylphosphite to hydrazones, derived from ben- zoylhydrazine and aliphatic ketones, is described. Reactions were successfully and catalytically promoted by BF3 etherate under mild condition in methylene chloride at room temperature.

Iron-Catalyzed Cross-Electrophile Coupling of Inert C–O Bonds with Alkyl Bromides

The “Groupement des Pharmacochimistes de l’Arc Atlantique” (GP2A) or Group of Medicinal Chemists of the Atlantic Arc is a study group on research and teaching in Medicinal Chemistry, which was created in 1992. It embraces medicinal chemists, mainly working in Faculties of Pharmacy and located in the different regions of the Atlantic Arc in the United Kingdom, France, Spain and Portugal. More recently, this grouping has welcomed new members who do not belong stricto sensu to this area (such as Lille, Saarbruck, Duesseldorf), in the framework of the GP2A network. This Grouping constitutes a focus for the exchange of ideas among scientists (including undergraduates) interested in basic research in medicinal chemistry but also in special areas of research in drug design, including combinatorial chemistry, quantitative structure-activity relationships and molecular modelling. GP2A gives an opportunity, especially to young scientists, to strengthen and extend their collaboration and exchange programmes. The circle is open to external participation and is mainly constituted on the basis of previously existing bilateral co-operations between various laboratories. At the instigation of the starting core, it was decided to hold a scientific meeting each year in the shape of the GP2A Conferences. In 2007, the Conferences were held in Bordeaux (University of Bordeaux 2 – Region Aquitaine) and were organized by the department of “Pharmacochimie” – EA 4138. At the start of the year 2007, there were more than 18,500 students in the University of Bordeaux 2 and a wide programme of courses is offered in medicinal & pharmaceutical sciences, oenology, sports, cognitic, social & human sciences. The main topics of the 2007 edition September 6 & 7, concerned microwave-assisted medicinal chemistry, conception and synthesis of new derivatives in the fight against cancer and parasitic diseases, place of crystallography in pharmaceutical chemistry, and development of radiopharmaceuticals. The steering committee makes a point of thanking all the young researchers of the various GP2A laboratories for the presentation of their work. Previous GP2A Conferences took place in Bordeaux (1992), Caen (1993), Cardiff (1994), Angers (1995), Glasgow (1996), Rennes (1997), Caen (1998), Cardiff (1999), Tours (2000), Nantes (2001), Caen (2002), La Rochelle (2003), Rennes (2004), Angers (2005), Bath (2006) and Bordeaux (2007); we look forward to attending an exciting meeting in Caen in 2008 (May 28–30).

The synthesis of new derivatives of 3-azabicyclononan is one of the urgent tasks of modern synthetic organic chemistry. 3-Azabicyclononan is a structural analogue of the cytisine alkaloid, which is a strong agonist of acetylcholine receptors. Among synthetic heterocycles containing a 3-azabicyclo[3.3.1]nonane fragment, compounds with different types of biological activity have been discovered at present: analgesic, anti-inflammatory, antimicrobial, antioxidant, and others. The introduction of a fragment of azabicyclononan into the amino acid structure can lead to a limitation of the conformational mobility of a new molecule, as a result of which the activity and selectivity of its interaction with the receptor will increase. We synthesized 2-(1,9-dinitro-8-oxo-6,11-diazatricyclo[7.3.1.02,7]trideca-2,4,6-trien-11-yl)acetic acid and 2-(1,9-dinitro-8-oxo-13-(2-oxopropyl)-6,11-diazatricyclo[7.3.1.02,7]trideca-2,4,6-trien-11-yl)acetic acid by the interaction of annionic σ-complexes 5,7-dinitro-8-hydroxyquinoline with glycine under Mannich condensation in high yield. At the beginning, when 5,7-dinitro-8-hydroxyquinoline NaBH4 was applied in DMF or acetone carbanion in DMSO, the corresponding anionic complexes were synthesized. The resulting adducts were isolated from the reaction mixture, dissolved in cold water, and an aminomethylating mixture consisting of formaldehyde and an amino acid was added. As a result, 3-azabicyclo[3.3.1]nonane derivatives are formed, annelated with a pyridine ring and containing an amino acid residue. By the methods of NMR and IR spectroscopy, as well as high-resolution mass spectrometry, the structure of the obtained compounds was proved. Thus, in the 1H NMR spectra of the synthesized compounds, a signal of the proton of the carboxyl group in the form of a broadened singlet is detected in a weak spectral region. Equatorial and axial protons of an alicyclic fragment form a characteristic system of signals in the range δ 3.20-3.60 ppm. In the IR spectra of these molecules, the vibrational bands of carbonyl groups at ν 1720 cm–1, as well as the vibrational bands of the C–O bond of the carboxyl group at ν 1198 cm–1, are fixed. The m/z values in the high resolution mass spectra correspond to the molecular weights of the synthesized diazatricycclotridecans.

Synthesis of new derivatives of 2-amino-4H-pyrans is reported via three-component reaction of α-ketoesters, active methylenes, and OH-acids in the presence of catalytic amount of piperidine at room temperature with high to excellent yields. The structure of synthesized compounds was characterized by FTIR, 1H, 13C NMR spectroscopy, and mass spectrometry. Simplicity of procedure, mild reaction conditions, short reaction time, and easy separation of the products make this an interesting alternative to other reported approaches. Also, their antibacterial and antioxidant activities were evaluated against Staphylococcus aureus and Bacillus subtilis as Gram-positive bacteria and Escherichia coli and Pseudomonas aeruginosa as Gram-negative bacteria, as well as the radical scavenger DPPH. Among these compounds, 4l including CO2Et substituent and 6-methyl-2H-pyran-2-one moiety showed the highest antioxidant and antibacterial activities.

Synthesis and structural modification of azoles remains an important area of medical chemistry and allows to obtain new compounds with a wide range of biological activity. Among the significant number of azoles, 1,3,4-thiadiazoles and 1,2,4-triazoles attract special attention, among which are known drugs, larvicides, insecticides, growth regulators, etc. Even though heterocyclizations of functionally substituted hydrazines for their synthesis are well studied, N-(R-hydrazine-1-carbonothioyl)cycloalkanecarboxamides, and nowadays, remain reagents with undiscovered potential. Moreover, the introduction of lipophilic “pharmacophore” fragments (cycloalkanes) in the structure of 1,3,4-thiadiazoles and 1,2,4-triazoles is a promising direction for their modification. That should provide additional intermolecular interactions with enzymes and may lead to enhancement or alteration of the biological activity vector. Thus, the synthesis of new derivatives of this class of compounds and the study of their antibacterial properties remains an urgent problem of medical and organic chemistry. Aim. To investigate the heterocyclization of N-(R-hydrazine-1-carbonothioyl)cycloalkanecarboxa-mides, to establish the structure and antibacterial activity of the synthesized compounds. Materials and methods. Methods of organic synthesis, physical and physical-chemical methods of analysis of organic compounds (NMR 1H-spectroscopy, chromato-mass spectrometry, elemental analysis). The antimicrobial activity of the synthesized compounds was studied according to the generally accepted method for standard strains of microorganisms and fungi. Results. The peculiarities of heterocyclization of N-(R-hydrazine-1-carbonothioyl)cycloalkanecarboxamides have been studied and the factors influencing this reaction have been elucidated. It was shown that these compounds under the conditions of the heterocyclization reaction in concentrated mineral acids form 5-R-2-amino-1,3,4-thiadiazoles. The intermediate undergoes additional hydrolysis by cleavage of the cycloalkanecarboxyl fragment. Alternative methods for the synthesis of 5-R-2-amino-1,3,4-thiadiazoles were proposed. For the first time, the original 4-cycloalkanecarbonyl-3-(amino-,phenyloxo-(thio)methyl-1,5-dihydro-4H-1,2,4-triazole-5-thiones were synthesized by prolonged heating of the corresponding disubstituted thiosemicarbazides. It was not possible to extend this reaction to other diacylthiosemicarbazides, the latter undergo heterocyclization in the presence of sodium hydroxide with the formation of the known 5-R-2,4-dihydro-3H-1,2,4-triazole-3-thiones. 1H NMR spectra were studied, analyzed, and regularities of splitting of characteristic protons in functionalized azoles were established. Conducted microbiological screening was showed that 5-R-2-amino-1,3,4-thiadiazoles, 4-cycloalkanecarbonyl-3-(amino-,phenyloxo-(thio)methyl-1,5-dihydro-4H-1,2,4-triazole-5-thiones and 5-R-2,4-dihydro-3H-1,2,4-triazole-3-thione were less effective antibacterial and antifungal agents (MIC 100–200 μg/ml) compared with N-(R-hydrazine-1-carbonothioyl)cycloalkanecarboxamides (MIC 3.125–200 μg/ml). Conclusions. It was found that N-(R-hydrazine-1-carbonotioyl)cycloalkane-carboxamides, depending on the conditions of heterocyclization form 5-R-2-amino-1,3,4-thiadiazoles, 3-(phenyloxo-(thio)methyl-1,5-dihydro-4H-1,2,4-triazole-5-thiones or 5-R-2,4-dihydro-3H-1,2,4-triazole-3-thiones. It was established that synthesized azoles were shown less effective antimicrobial and antifungal activity in comparison with N-(R-hydrazine-1-carbonothioyl)cycloalkanecarboxamides.

Molecular Structural Evolution of Near-Infrared Cationic Aggregation-Induced Emission Luminogens: Preclinical Antimicrobial Pathogens Activities and Tissues Regeneration

Self-Assembly Ultrathin Fe-Terephthalic Acid as Synergistic Catalytic Platforms for Selective Hydrogenation

DABCO‐diacetate (1,4‐diazabicyclo[2.2.2]octaniumdiacetate) was synthesized and applied as a green media for the synthesis of new derivatives of benzo[d]imidazole with azo‐linked core and bis benzo[d]imidazoles via condensation reaction of aldehydes and 1,2‐diaminobenzene under solvent‐free conditions. This procedure has benefits such as: good productivity with high yield, short reaction times, easy and efficient process, environmental friendliness, and green aspect of chemistry. DABCO‐diacetate is reusable and can be used for eight runs without notable loss of activity. All of synthesized compounds are new and were characterized completely.

Controllable Polymerization of <i>N</i> -Substituted β-Alanine <i>N</i> -Thiocarboxyanhydrides for Convenient Synthesis of Functional Poly(β-peptoid)s