Ring Derivatives Research Articles

Some identities involving generalized (α,β)-derivations in prime and semiprime rings

Let [Formula: see text] be a prime or semiprime ring, [Formula: see text] a nonzero left-sided ideal of [Formula: see text] and [Formula: see text] be two automorphisms of [Formula: see text]. Let [Formula: see text] and [Formula: see text] be two generalized [Formula: see text]-derivations of [Formula: see text] associated with [Formula: see text]-derivations [Formula: see text] and [Formula: see text], respectively. The purpose of this paper is to investigate the following identities: (1) [Formula: see text]; (2) [Formula: see text]; (3) [Formula: see text]; (4) [Formula: see text]; (5) [Formula: see text]; (6) [Formula: see text]; (7) [Formula: see text]; (8) [Formula: see text]; (9) [Formula: see text]; (10) [Formula: see text]; (11) [Formula: see text]; (12) [Formula: see text], for all [Formula: see text].

Recent Progress in the Multicomponent Synthesis of Pyran Derivatives by Sustainable Catalysts under Green Conditions.

Pyrans are one of the most significant skeletons of oxygen-containing heterocyclic molecules, which exhibit a broad spectrum of medicinal applications and are constituents of diverse natural product analogues. Various biological applications of these pyran analogues contributed to the growth advances in these oxygen-containing molecules. Green one-pot methodologies for synthesising these heterocyclic molecules have received significant attention. This review focuses on the recent developments in synthesising pyran ring derivatives using reusable catalysts and emphasises the multicomponent reaction strategies using green protocols. The advantages of the catalysts in terms of yields, reaction conditions, and recyclability are discussed.

On b-generalized derivations in prime rings

On b-generalized derivations in prime rings

Computational Evaluation of Polycyclic Bis-Oxadiazolo-Pyrazine Backbone in Designing Potential Energetic Materials

4H,8H-bis[1,2,5]oxadiazolo[3,4-b:3',4'-e]pyrazine (bis-oxadiazolo-pyrazine) represents a versatile CHNO backbone for the design of energetic materials. In this paper, we report a comprehensive computational study using density functional theory to improve detonation properties of this CHNO backbone by introducing pyrazine rings, nitro groups, and N-oxide functionalities. The heat of formation, oxygen balance, density, and detonation properties of a series of furazan-pyrazine fused ring derivatives are computed. Their sensitivity and stability has been correlated with bandgap (ΔELUMO-HOMO), maximum heat of detonation (Q), and impact energy (h50). Introduction of –NO2 and N–oxide on the parent furazan-pyrazine fused ring derivatives is favorable for improving the heat of formation, oxygen balance and density. The heat of formation varies between 464.46 and 1043.57 kJ/mol, and the densities range from 1.75 to 2.01 g/cm3. The positive heat of formation and high densities achieved good detonation velocities (6.74 to 9.61 km/s) and pressures (19.96–43.65 GPa). Among the bis-oxadiazolo-pyrazine derivatives, P5, P6, Q5, Q6, R4, R5, and R6 are fascinating due to their high detonation performances, have calculated detonation velocities and pressures above 9.30 km/s and 40.0 GPa, respectively. Some furazan-pyrazine fused ring derivatives reveal good performance parameters with reasonable stability, confirming them as potential energetic compounds relative to RDX and HMX.

Guanidinates as Alternative Ligands for Organometallic Complexes.

For decades, ligands such as phosphanes or cyclopentadienyl ring derivatives have dominated Coordination and Organometallic Chemistry. At the same time, alternative compounds have emerged that could compete either for a more practical and accessible synthesis or for greater control of steric and electronic properties. Guanidines, nitrogen-rich compounds, appear as one such potential alternatives as ligands or proligands. In addition to occurring in a plethora of natural compounds, and thus in compounds of pharmacological use, guanidines allow a wide variety of coordination modes to different metal centers along the periodic table, with their monoanionic chelate derivatives being the most common. In this review, we focused on the organometallic chemistry of guanidinato compounds, discussing selected examples of coordination modes, reactivity and uses in catalysis or materials science. We believe that these amazing ligands offer a new promise in Organometallic Chemistry.

4-Aminocoumarin Derivatives as Multifaceted Building Blocks for the Development of Various Bioactive Fused Coumarin Heterocycles: A Brief Review

Abstract: Aminocoumarins are found to be present in many natural products, pharmaceuticals, and organic materials. These derivatives demonstrate numerous biological activities including DNA gyrase, anti-proliferative and anti-breast cancer activities. Among the allaminocoumarin derivatives, 4-aminocoumarin derivatives have been reported to exhibit anticancer and anti-fungal properties. 4-Aminocoumarins and their derivatives are important precursors for the synthesis of coumarin fused N-heterocycles. Due to the presence of an amino group as well as enamine carbon, it is very reactive towards electrophiles and in most of the cases, it has a higher tendency to cyclize immediately by the various reaction path ways and provides the heterocyclic products. Unlike other aromatic amines, it did not give any Schiff base on reaction with aldehydes or ketones. Lamellarins, ningalin A, ningalin B, schumanniophytin, santiagonamine, goniothaline, and polyneomarline C are important natural coumarin fused N-heterocycles and show excellent biological activities, including antitumor, reversal of multidrug resistance, anti-HIV, wound healing, anti-malarial, anti-hepatitis, and anti-syphilis activities. The synthesized coumarin fused N-heterocycles have been reported to display Topoisomerases I inhibitory, DYRK1A inhibitory, and anti-cancer activities. Most of the syntheses of pyrrolo/imidazolo/indolo[3,2-c]coumarin, pyrido/quinolino[3,2-c]coumarins, pyrimidino[ c]coumarin and oxazino[c]coumarin have been synthesized easily from 4-aminocoumarin. This paper reviews the research data in the literature on the synthesis of bioactive coumarin fused heterocycles using 4-aminocoumarin derivatives over the period of 2-3 decades. It covers the synthetic applicability of 4-aminocoumarin for the development of coumarin fused 5-, 6-, and 8-membered ring derivatives via classical reaction protocols, microwavemediated reactions, organo-catalyzed reactions, transition metal-catalyzed reactions, and green reaction protocols.

Preparation of Polyphenylene Ring Derivative Dyes with Wide Wave Absorption Properties and Their Performance Study.

Some conjugated benzene ring molecules were prepared using the Sonogashira reaction, and the molecules were post-functionally modified using click chemistry. The optical and electrical band gaps were measured using UV-VIS absorption spectroscopy and the three-electrode method, and the results of both were verified against each other to prove the accuracy of the characterization. In addition, the optical performances of the material were studied by z-scan; almost all materials exhibited good nonlinear optical properties and interconversion between saturable and anti-saturable absorption due to the invocation of click reagents.

Synthesis of benzo-condensed cyclic cathinone derivatives

Recently, the number of new psychoactive substances (NPS), which are sold as legal alternatives to conventional or misused drugs, has been growing on the market. Via small chemical modifications in the basic structure of the already banned substances, new derivatives are made. Although they pose a real threat to human health, they do circumvent regulation system. This fact led us to formulate the aim of this work, which is the synthesis of cyclic derivatives of cathinones, substances that are derived from natural substance S-cathinone. All commercial reagents and solvents were used without additional purification. 1H NMR and 13 C NMR spectra measured for structure conformation were acquired on an Agilent 400-MR DDR2 spectrometer with CDCl3 or CH3OD as the solvent. Cyclic derivatives of cathinone with different size of benzo-condensed ring were prepared using different synthetic approaches optimised to maximum possible yields. The first intermediate with a six membered condensed ring was synthesised using a nucleophilic addition of an aryllithium on cyclobutanone to form corresponding cyclobutanol derivative. This alcohol was transferred to an α-tetralone system using a radical cyclization reaction with potassium peroxodisulfate and silver nitrate. A cycliclization reaction of differently substituted 4-arylbutanoic acids employing polyphosphoric acid was used as a second approach. Also, five and four membered condensed ring derivatives were synthesised using two different approaches. The first approach was based on Friedel-Crafts acylation, where phenylpropanoic and phenylethanoic acid were converted to chlorides using oxalyl chloride, then using aluminium (III) chloride as a catalyst the intramolecular ring-closing reaction was completed. The second approach was cyclization of acids by means of thionyl chloride and trifluoromethanesulfonic acid. The benzocycloheptane ring was prepared using all cyclization reactions mentioned above. All the above-described intermediates were subsequently subjected to the sequence of reactions to prepare the final derivatives. A reaction of cyclic ketones with isoamyl nitrite provided oximes which were reduced with zinc dust in acetic acid to form acetamides. These acetamides were hydrolysed using hydrochloric acid yielding corresponding amines. These amines were transformed to trifluoroacetamides, which were methylated using iodomethane and the final step, acid hydrolysis gave rise to the target N-methylated cyclic derivatives. Different approaches towards the synthesis of benzocondensed bicyclic ketones with various sizes of the aliphatic ring are presented. These compounds have been used as intermediates to prepare new cyclic cathinones and their formal metabolites (N-demethylated derivatives). All the novel substances are fully characterized and, moreover, the possibility of their chiral separation using HPLC is being studied to assign their absolute configuration and study the biological activity of enantiomers.

Mechanisms of polystyrene microplastic degradation by the microbially driven Fenton reaction

Natural hydroxyl radical (·OH) production, which partially occurs through the microbially driven Fenton reaction, can enhance the degradation of polystyrene microplastics (PS-MPs). However, ·OH causes damage to microorganisms, which might in turn restrain the microbially driven Fenton reaction. Thus, whether PS-MPs can be continuously degraded by the microbially driven Fenton reaction and how they are degraded are still unknown. A pure-culture system using Shewanella putrefaciens 200 was set up to explore the effect and mechanism of microbially driven Fenton reaction on PS-MP degradation. In a 14-day operation, ·OH produced by the microbially driven Fenton reaction could degrade PS-MPs with a weight loss of 6.1 ± 0.6% and an O/C ratio of 0.6 (v.s. 0.6 ± 0.1% and 0.1, respectively, in the ·OH quenched group). Benzene ring derivatives such as 2-isopropyl-5-methyl-1-heptanol and nonahexacontanoic acid were the main soluble products of PS-MP degradation. The ·OH-induced oxidative damage on microorganisms did not affect ·OH production significantly when there was timely replenishment of organic carbon sources to promote reproduction of microorganisms. Thus, PS-MPs can be continuously degraded by microbially driven Fenton reactions in natural alternating anaerobic-aerobic environments. This study also provides a new microbial technique for MP degradation that is different from previous technologies based on microbial plastic-degrading enzymes.

Nutritional inter-dependencies and a carbazole-dioxygenase are key elements of a bacterial consortium relying on a Sphingomonas for the degradation of the fungicide thiabendazole.

Thiabendazole (TBZ), is a persistent fungicide/anthelminthic and a serious environmental threat. We previously enriched a TBZ-degrading bacterial consortium and provided first evidence for a Sphingomonas involvement in TBZ transformation. Here, using a multi-omic approach combined with DNA-stable isotope probing (SIP) we verified the key degrading role of Sphingomonas and identify potential microbial interactions governing consortium functioning. SIP and amplicon sequencing analysis of the heavy and light DNA fraction of cultures grown on 13 C-labelled versus 12 C-TBZ showed that 66% of the 13 C-labelled TBZ was assimilated by Sphingomonas. Metagenomic analysis retrieved 18 metagenome-assembled genomes with the dominant belonging to Sphingomonas, Sinobacteriaceae, Bradyrhizobium, Filimonas and Hydrogenophaga. Meta-transcriptomics/-proteomics and non-target mass spectrometry suggested TBZ transformation by Sphingomonas via initial cleavage by a carbazole dioxygenase (car) to thiazole-4-carboxamidine (terminal compound) and catechol or a cleaved benzyl ring derivative, further transformed through an ortho-cleavage (cat) pathway. Microbial co-occurrence and gene expression networks suggested strong interactions between Sphingomonas and a Hydrogenophaga. The latter activated its cobalamin biosynthetic pathway and Sphingomonas its cobalamin salvage pathway to satisfy its B12 auxotrophy. Our findings indicate microbial interactions aligning with the 'black queen hypothesis' where Sphingomonas (detoxifier, B12 recipient) and Hydrogenophaga (B12 producer, enjoying detoxification) act as both helpers and beneficiaries.

Factors Governing Reactivity and Selectivity in Hydrogen Atom Transfer from C(sp3)-H Bonds of Nitrogen-Containing Heterocycles to the Cumyloxyl Radical.

A kinetic study of the hydrogen atom transfer (HAT) reactions from nitrogen-containing heterocycles (secondary and tertiary lactams, 2-imidazolidinones, 2-oxazolidinones, and succinimides) to the cumyloxyl radical has been carried out employing laser flash photolysis with ns time resolution. HAT occurs from the C–H bonds that are α to nitrogen, activated by hyperconjugative overlap with the N–C=O π system. In the lactam series, the second-order HAT rate constant (kH) was observed to decrease by a factor of ∼4 going from the five- and six-membered ring derivatives to the eight-membered ones, a behavior that was rationalized on the basis of a reduced extent of hyperconjugative activation associated to the greater flexibility of the larger rings compared to the smaller ones. In the five-membered-ring substrate series, the kH values were observed to increase by >3 orders of magnitude on going from succinimide to 2-imidazolidinones, a behavior that was explained in terms of the divergent contribution of hyperconjugative activation and deactivating electronic effects determined by ring functionalities. The results are discussed in the framework of the development of HAT-based C–H bond functionalization procedures.

Some identities related to multiplicative (generalized)-derivations in prime and semiprime rings

Some identities related to multiplicative (generalized)-derivations in prime and semiprime rings

Cytochalasins from coastal saline soil-derived fungus Aspergillus flavipes RD-13 and their cytotoxicities.

Chemical investigation of coastal saline soil-derived fungus Aspergillus flavipes RD-13 led to the isolation of two new seco-cytochalasins (1) and (2) along with nine known analogs. Their structures were elucidated by comprehensive spectral analysis, and the absolute configurations of these two new ones were determined through Rh2(OCOCF3)4-induced CD experiment and chemical interconversions. Moreover, the absolute configuration of a known compound named cytochalasins Z18 (3) was also determined for the first time. Structurally, compounds 1, 2 and 3 were the open ring derivatives of compounds 5, 8, and 4, respectively. All compounds were evaluated for their cytotoxic activities on A549, H1299 and H520 cells and 4 exhibited the strongest inhibitory activities towards the above cell lines with IC50 values of 0.15, 0.23 and 0.43 μg/mL, respectively. Preliminary structure-activity relationship analysis suggested the importance of macrocyclic ring in cytochalasins to confer cytotoxicity.

Derivations of triangular matrix rings

In this paper, the author gives a description of the derivations of , the ring of upper triangular matrices over an associative ring R with identity. The main result states that if D is an arbitrary derivation of the ring and , then there are matrices, such that the derivative is a linear combination of the values of well-known derivations of these matrices.

Product and commuting generalized derivations in prime rings

Product and commuting generalized derivations in prime rings

Novel Dioxolane Ring Compounds for the Management of Phytopathogen Diseases as Ergosterol Biosynthesis Inhibitors: Synthesis, Biological Activities, and Molecular Docking.

Thirty novel dioxolane ring compounds were designed and synthesized. Their chemical structures were confirmed by 1H NMR, HRMS, and single crystal X-ray diffraction analysis. Bioassays indicated that these dioxolane ring derivatives exhibited excellent fungicidal activity against Rhizoctonia solani, Pyricularia oryae, Botrytis cinerea, Colletotrichum gloeosporioides, Fusarium oxysporum, Physalospora piricola, Cercospora arachidicola and herbicidal activity against lettuce (Lactuca sativa), bentgrass (Agrostis stolonifera), and duckweed (Lemna pausicostata). Among these compounds, 1-((2-(4-chlorophenyl)-5-methyl-1,3-dioxan-2-yl)methyl)-1H-1,2,4-triazole (D17), 1-(((4R)-2-(4-chlorophenyl)-4-methyl-1,3-dioxolan-2-yl)methyl)-1H-1,2,4-triazole (D20), 1-((5-methyl-2-(4-(trifluoromethyl)phenyl)-1,3-dioxan-2-yl)methyl)-1H-1,2,4-triazole (D22), and 1-((2-(4-fluorophenyl)-1,3-dioxolan-2-yl)methyl)-1H-1,2,4-triazole (D26) had broad spectrum fungicidal and herbicidal activity. The IC50 values against duckweed were 20.5 ± 9.0, 14.2 ± 6.7, 24.0 ± 11.0, 8.7 ± 3.5, and 8.0 ± 3.1 μM for D17, D20, D22, and D26 and the positive control difenoconazole, respectively. The EC50 values were 7.31 ± 0.67, 9.74 ± 0.83, 17.32 ± 1.23, 11.96 ± 0.98, and 8.93 ± 0.91 mg/L for D17, D20, D22, and D26 and the positive control difenoconazole against the plant pathogen R. solani, respectively. Germination experiments with Arabidopsis seeds indicated that the target of these dioxolane ring compounds in plants is brassinosteroid biosynthesis. Molecular simulation docking results of compound D26 and difenoconazole with fungal CYP51 P450 confirmed that they both inhibit this enzyme involved in ergosterol biosynthesis. The structure-activity relationships (SAR) are discussed by substituent effect, molecular docking, and density functional theory analysis, which provided useful information for designing more active compounds.

Design, synthesis and biological screening of novel heterocyclic ring derivatives as antibacterial agents

For a long time, numerous attempts are being made by researchers to discover and develop new antimicrobial agents based on synthetic compounds and medicinal plants. These attempts were forced due to increasing rate of microbial resistance. In the present study, it has been discussed that the synthesis of various dihydropyrimidine fused with benzimidazole moiety. In which o-phenylenediamine and chloroacetic acid react in acidic medium by nucleophilic addition reaction to form 2-chloro methyl Benzimidazole. (1). The substituted Chalcone (2) was synthesized by a claisan-schmidt condensation reaction. The condensation of an aromatic aldehyde with aromatic ketone having α- hydrogen in presence of a strong base to form α,β-unsaturated ketone i.e Chalcone is form. The substituted Chalcone react with thiourea by Michael reaction. It is also called 1,4 addition reaction. In which thiourea act as nucleophile attack on 4-positon of the α,β-unsaturated ketone and keto-enol tautomerism occurs and 4- substitutedphenyl-6-substitutedphenyl-4,5-dihydropyrimidine-2- thiol . (3). Benzimidazole (1) fused with substituted dihydropyrimidine-2-thiol (3) in presence of THF and form 2-((4-substituted phenyl-6-substituted phenyl pyrimidine-2-ylthio)methyl)-1H-benzo[d]imidazole. (4). The synthesized compounds APUS1 – APUS21 were assigned by its spectral data (IR, NMR and mass spectra). The synthesized compounds have been tested for their antibacterial activity against Gram (+) bacteria (S. aureus) , (B.subtilis) and Gram (-) bacteria (E.coli ) by agar diffusion method. Compound having electron withdrawing group show significant activity and having electron donor group show moderate activity. Keywords: Antibacterial activity, Molecular docking, Dihydropyrimidine, Benzimidazole.

Synthesis of Novel Derivatives of 5,6,7,8-Tetrahydroquinazolines Using α-Aminoamidines and In Silico Screening of Their Biological Activity.

α-Aminoamidines are promising reagents for the synthesis of a diverse family of pyrimidine ring derivatives. Here, we demonstrate the use of α-aminoamidines for the synthesis of a new series of 5,6,7,8-tetrahydroquinazolines by their reaction with bis-benzylidene cyclohexanones. The reaction occurs in mild conditions and is characterized by excellent yields. It has easy workup, as compared to the existing methods of tetrahydroquinazoline preparation. Newly synthesized derivatives of 5,6,7,8-tetrahydroquinazoline bear protecting groups at the C2-tert-butyl moiety of a quinazoline ring, which can be easily cleaved, opening up further opportunities for their functionalization. Moreover, molecular docking studies indicate that the synthesized compounds reveal high binding affinity toward some essential enzymes of Mycobacterial tuberculosis, such as dihydrofolate reductase (DHFR), pantothenate kinase (MtPanK), and FAD-containing oxidoreductase DprE1 (MtDprE1), so that they may be promising candidates for the molecular design and the development of new antitubercular agents against multidrug-resistant strains of the Tubercle bacillus. Finally, the high inhibition activity of the synthesized compounds was also predicted against β-glucosidase, suggesting a novel tetrahydroquinazoline scaffold for the treatment of diabetes.

Weak Jordan *-derivations of prime rings

Let * be an involution of a non-commutative prime ring [Formula: see text] with the maximal symmetric ring of quotients and the extended centroid of [Formula: see text] denoted by [Formula: see text] and [Formula: see text], respectively. Consider [Formula: see text] be an additive map, if [Formula: see text] for all [Formula: see text], then such a map [Formula: see text] is termed as a weak Jordan *-derivation. With the smart handling of the FI-theory and facing the challenging case of low dimensions, we prove that every weak Jordan *-derivation of [Formula: see text] is [Formula: see text]-inner unless [Formula: see text]. Moreover, if * is of the first kind, then every weak Jordan *-derivation [Formula: see text] of [Formula: see text] is [Formula: see text]-inner if and only if [Formula: see text] is [Formula: see text]-linear.

Exploration of novel phthalazinone derivatives as potential efflux transporter inhibitors for reversing multidrug resistance and improving the oral absorption of paclitaxel

Chemotherapy is an important means of cancer treatment. However, overexpression of efflux transporters (including but not limited to P-gp and BCRP) can lead to resistance to cancer chemotherapy. Multiple-target inhibitors of efflux transporter can be overcome the resistance and improve the oral bioavailability of chemotherapy drugs. Therefore, we designed and synthesized a series of phthalazinone ring derivatives (1-20) with different aromatic heterocycles substituents on the amide bond for dual inhibition of P-gp and BCRP. Most target compounds significantly increased the accumulation of P-gp substrates in the chemo-resistant cancer cell lines by inhibiting the efflux of transporters. Compound 19 in particular showed stronger MDR reversal compared to Gefitinib and Verapamil, and comparable to that of the BCRP inhibitor Ko143. In addition, compound 19 improved intestinal absorption of paclitaxel (PTX) and enhanced the bioavailability of the orally administered drug in vivo.