Title Compounds Research Articles

Microwave and ultrasound-assisted green protocols for 5-methylthiazole induced Betti bases: molecular docking, in-silico pharmacokinetics, and anticancer activity studies

ABSTRACT Herein, we describe an efficient one-pot three-component microwave and ultrasound-endorsed approaches for synthesizing distinct 5-methylthiazole induced Betti bases (5-methyl-thiazol-2-ylamino-aryl-benzylnapthols) employing silica sulfuric acid (SSA, silica-OSO3H) as an active heterogeneous acid catalyst. The title compounds produced in good yields (86–95%) from naphthalen-2-ol, 5-methylthiazol-2-amine, and assorted aryl aldehydes; and structurally characterized by spectral and elemental analyses. A comprehensive comparative study of conventional, ultrasonic, and microwave-irradiated synthetic routes has been achieved by optimizing various reaction parameters. These new protocols provide several advantages, including the use of an inexpensive, non-toxic, and reusable catalyst. Additionally, they benefit from mild reaction conditions, short reaction times, and simple workup and purification procedures, thereby increasing their practicality. Furthermore, the synthesized compounds were evaluated for their anticancer potency against A-549 (lung cancer) and A-498 (kidney cancer) cell lines, with scaffold IVa demonstrating excellent (GI50 < 10 µg/mL) inhibitory activity against A-549. Additionally, molecular docking was performed to investigate potential binding interactions between ligands and proteins. Scaffold IVa exhibited the best docking with cancerous target proteins 1M17 (−8.9 kcal/mol) and 1M14 (−7.2 kcal/mol), thereby supporting our bio-activity studies.

3,4-Dihydropyrimidine-2(1H)-one/thione Derivatives as Anti-inflammatory and Antioxidant Agents: Synthesis, Biological Activity, and Docking Studies

aims: A series of sixteen new 4-(substituted phenyl) - 6-(substituted phenylamino)-3, 4-dihydropyrimidine-2(1H)-ones/thiones derivatives have been synthesized in two step reaction. background: Free radicals are widely known to play a significant part in the inflammatory process. Many non-steroidal anti-inflammatory medicines have been shown to work as radical scavengers or as inhibitors of free radical generation. Inflammation is a part of the vascular tissues&amp;#039; complicated biological reaction to adverse stimuli like bacteria, damaged cells, or irritants. The organism&amp;#039;s protective response to damaging stimuli is inflammation, which aims to get rid of them and start the healing process. The inflammatory response has several advantageous effects, such as stopping the spread of dangerous substances to nearby tissues, getting rid of cell waste and infections, and getting the body ready for repair objective: To synthesize new derivatives as anti-inflammatory and antioxidant agents. method: In first step chalcones (I1-I6) was obtained and in the second step, these chalcones were reacted with urea and thiourea in the presence of potassium hydroxide to obtain the corresponding pyrimidinones and thiopyrimidinones. The structures of the synthesized compounds 4-(substituted phenyl)-6-(substituted phenylamino)-3,4-dihydropyrimidine-2(1H)-ones/thione derivatives are investigated by means of TLC (visualized it in Iodine chamber), IR, mass, 1H-NMR spectral and elemental analysis. The title compounds evaluated for anti-inflammatory as well as antioxidant activity. Anti-inflammatory activity in vivo was carried out by carrageenan induced rat-paw edema method and compared with standard drug diclofenac sodium and antioxidant activity was measured by DPPH, FRAP and Hydrogen peroxide (H2O2) method and compared with standard ascorbic acid. result: Electron donating groups showed better antioxidant activity as compared to electron withdrawing ones in both activities. All the compounds exhibited good to moderate activity. Compound DHPM8 shows better antioxidant activity and compound DHPM6 shows better anti-inflammatory activity while compound DHPM11 shows minimum antioxidant as well as anti-inflammatory activity than other compounds. conclusion: To better understanding, we have performed molecular docking simulation. The molecular docking studies revealed that all synthesized compound were showed good receptor binding interaction in which compound 9 had highest docking score of 9.8 due to interaction with CYS36, PRO153, TYR130, GLY45, LEU152, ARG469, LYS468 and GLU465. other: NA

Synthesis of β-lactams and transformation to β-amino acid ethyl ester derivatives: Theoretical calculations

Because of the important biological properties of β-amino acids in the present work, two new β-amino acid ethyl ester derivatives were synthesized, and their mechanistic occurrence was investigated. The title compounds were synthesized from related tetralone derivatives containing bromine and methoxy groups. Tetralone derivatives were reduced to their benzyl alcohol derivatives with NaBH4, followed by elimination with p-toluenesulfonic acid (pTSA) to give the desired 1,2-dihydronaphthalene derivatives. The reactions of 1,2-dihydronaphthalenes with chlorosulfonyl isocyanate (CSI) afforded β-lactams. β-Amino acids were obtained from the reaction of β-lactams with EtOH in HCl. Computational studies are concerned with synthesizing four-membered lactams (β-lactam) formed by the reaction between 1,2-dihydronaphthalene derivatives and CSI. The mechanism of the formation of compounds has been elucidated using DFT at M06-2X.

Exploring the anticancer properties of indole pyrimidine derivatives: Synthesis, structural insights, docking analysis, and in vitro evaluation

The nitrogen containing heterocyclic and chalcones moiety widely recognized as favorable combination of diagnostic and therapeutic facilities in medicinal chemistry. In particular, indole analogs play a very important medicinal role in pharmacology activities, hence, drugs like pindolol, indomethacin, oxypertine, ellipticine, arbidol and ate viridine are well known in market. In this view, the title compounds 4(a-j) were synthesized in good yield. The purified compounds were explained by spectroscopic procedures (FT-IR, 1H NMR, 13CNMR, and LC-MS), and lastly, all synthetic compounds have in-vitro efficacy assessed against the HeLa human cervical cancer and MCF-7 human breast cancer cell lines, and their efficacy was compared to that of the well-known anticancer drug methotrexate (Methotrexate). Compounds 4a, 4b, 4c, and 4e from the series (4a-j) demonstrated the most notable inhibitory activity. The cytotoxicity evaluation of these newly synthesized compounds revealed that 4a, 4b, 4c, and 4e were the most toxic to HeLa cells, with IC50 values for growth inhibition of 20.41 ± 3.14, 23.54 ± 3.27, 24.77 ± 2.14, and 26.10 ± 1.58, respectively. These compounds exhibited an even stronger growth-inhibitory effect on MCF-7 cells, with IC50 values of 18.84 ± 2.69, 19.45 ± 3.14, 22.83 ± 2.68, and 21.80 ± 1.68, respectively. In comparison, methotrexate (Methotrexate) showed IC50 values of 28.29 ± 1.0 for HeLa cells and 45.08 ± 2.61 for MCF-7 cells. Additionally, compounds 4a, 4b, 4c, and 4e played a crucial role in interacting with the catalytic domain of PDE3, demonstrating IC50 values for PDE3A inhibition of 8.05 ± 1.27, 7.55 ± 2.14, 15.09 ± 1.54, and 17.12 ± 3.14, respectively. These results are compared with Cilostazol, a known PDE inhibitor, which exhibited an IC50 of 0.00368 ± 3.14. In-silico studies revealed that compounds (4a, 4b, and 4c) are comparatively very efficient in binding with PDE3A which was further validated with MMGBSA and MDSs.

New cyano-acrylamide derivatives incorporating the thiophene moiety: Synthesis, anti-cancer, gene expression, DNA fragmentation, DNA damage, and in silico studies

New cyano-acrylamide derivatives bearing the thiophene structure were prepared and rigorously characterized. Thus, the reaction of diethyl 5-(2-cyanoacetamido)-3-methylthiophene-2,4-dicarboxylate with aldehydes in the presence of piperidine afforded the title compounds in very good to excellent yields (range 81-96%, mean 91%). All the newly synthesized compounds were evaluated as anti-cancer agents against five human cancer cell lines namely, MCF7 (human Caucasian breast adenocarcinoma), PC3 (human prostate cancer cell line), HepG2 (Human hepatocellular carcinoma), PACA2 (epithelial cell line derived from tumor tissue of pancreas), and BJ1 (normal skin fibroblast). While most of the compounds showed good activity against MCF-7, they showed limited activity against PC3, HepG2, and PACA2. Compound 9 showed potent anti-cancer activity against the PACA2 cell line with IC50 131.18 µM compared with the reference drug (doxorubicin, IC50 52.06 µM), while compound 10 exhibited potent anti-cancer activity against HePG2 cell lines with IC50 24.51 µM compared to the positive control (doxorubicin, IC50 39.73 µM). The gene expression, DNA fragmentation, and DNA damage of the most promising compounds were discussed. Additionally, compounds 9 and 10 showed favorable binding energies and strong interactions with CDK2, EGFR, ERα, VEGFFR, and Topoisomerase II receptors in the molecular docking simulation. These results suggest that these compounds have the potential to be effective candidates for anti-cancer therapy. Additionally, the in-silico ADMET profiles indicated that these compounds adhere to the Lipinski rules, indicating favorable physicochemical properties. These findings further support their potential for continued drug development efforts.

Design, synthesis and docking studies of new molecular hybrids bearing benzimidazole and thiazolidine-2,4-dione as potential antitubercular agents

Finding novel therapeutic medications to combat tuberculosis (TB) is crucial, as evidenced by the disease's growth as a worldwide health concern in recent decades and the rise of drug-resistant forms of Mycobacterium tuberculosis (Mtb). In this article, we describe the synthesis and design of a novel class of thiazolidine-2,4-dione derivatives (5a-i) based on 1H-benzo [d]imidazoles as antitubercular drugs. Spectroscopic techniques and elemental analysis were used to characterize each of the newly synthesized molecules. The antitubercular activity of all the newly synthesized title compounds was assessed against drug-sensitive Mtb H37Rv, multidrug-resistant (MDR-TB), and extensively drug-resistant (XDR-TB) tuberculosis. Compounds 5e and 5 h had the most antitubercular activity among all the newly synthesized hybrids against drug-sensitive, MDR-TB, and XDR-TB strains, with MIC values ranging from 0.21 to 47.84 μM. When it comes to drug-sensitive, drug-resistant, and XDR Mtb strains, compound 5 h with a trifluoromethyl group is 1.71, 10.86, and 3.50 times more potent, whereas compound 5e with a nitro group is 1.12, 8.50, and 2.61 times more active. Remarkably, the compounds' in vitro cytotoxicity test demonstrated good selectivity indices, highlighting their safety on the normal lung fibroblast (WI-38) cell line experiment. To further understand the interactions between potent hybrids and the target enzyme, molecular docking investigations were conducted against the decaprenyl-phosphoryl-ribose 2′-epimerase (DprE1) enzyme. The target protein exhibited preferentially positive interactions with the potent compounds 5e, 5f, 5 h, and 5i. Relationships between structure-activity as well as drug-likeness were used to connect the freshly synthesized compounds' physical and biological properties. When considered collectively, these results suggest that compounds 5e and 5 h might be promising candidates for the development of drug-sensitive and drug-resistant TB therapies in the future.

Synthesis of Diastereomeric 2,6-bis{[3-(2-Hydroxy-5-substitutedbenzyl)octahydro-1H-benzimidazol-1-yl]methyl}-4-substituted Phenols (R = Me, OMe) by Mannich-Type Tandem Reactions

The synthesis and characterization of two novel diastereomeric Mannich bases was carried out from the reaction of the cyclic aminal (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo[8.8.1.1.8,170.2,70.11,16]icosane 1 and p-cresol 2a and 4-methoxyphenol 2b in a water/dioxane mixture. The title compounds (4a–b) are interesting because bearing two 3-(2-hydroxy-5-substitutedbenzyl)octahydro-1H-benzimidazol-1-yl]methyl} substituents joined to an arenol ring. The formation of these new Mannich bases in the reaction mixture can be explained by aminomethylation of previously reported di-Mannich base 2,2′-((hexahydro-1H-benzo[d]imidazole-1,3(2H)-diyl)bis(methylene))bis(4-substituentphenol) 3a–b. NMR analysis demonstrated that compounds 4a–b were formed as diastereomeric mixtures. Subsequent experiments revealed that at longer reaction times, the percentage yield of these new products increased considerably (yield percentages up to 22–27%), suggesting a nucleophilic competition between the p-substituted phenols and Mannich bases of type 3 for aminal 1.

An Overview on the Synthesis of Lamellarins and Related Compounds with Biological Interest.

Lamellarins are natural products with a [3,4]-fused pyrrolocoumarin skeleton possessing interesting biological properties. More than 70 members have been isolated from diverse marine organisms, such as sponges, ascidians, mollusks, and tunicates. There is a continuous interest in the synthesis of these compounds. In this review, the synthetic strategies for the synthesis of the title compounds are presented along with their biological properties. Three routes are followed for the synthesis of lamellarins. Initially, pyrrole derivatives are the starting or intermediate compounds, and then they are fused to isoquinoline or a coumarin moiety. Second, isoquinoline is the starting compound fused to an indole moiety. In the last route, coumarins are the starting compounds, which are fused to a pyrrole moiety and an isoquinoline scaffold. The synthesis of isolamellarins, azacoumestans, isoazacoumestans, and analogues is also described. The above synthesis is achieved via metal-catalyzed cross-coupling, [3 + 2] cycloaddition, substitution, and lactonization reactions. The title compounds exhibit cytotoxic, multidrug resistance (MDR), topoisomerase I-targeted antitumor, anti-HIV, antiproliferative, anti-neurodegenerative disease, and anti-inflammatory activities.

Phenyldiazenyl-phenoxy-1,2,3-triazol-acetamide derivatives as new dual cholinesterase Inhibitors: Design, synthesis, in vitro, and in silico enzymatic inhibition evaluations

In this work, phenyldiazenyl-phenoxy-1,2,3-triazol-acetamide as new scaffold was designed by molecular hybridization of the active pharmacophores in the cholinesterase inhibitors. Twelve derivatives 7a-l of the title scaffold were synthesized in high yields using simple and efficient chemical reactions. The inhibitory activities of all the title compounds 7a-l were investigated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as two important enzymatic targets in Alzheimer's disease (AD). The obtained in vitro data showed that all new compounds were more potent than positive control galantamine against both studied enzymes. Representatively, the most potent compound against AChE (compound 7 g) was 2.7-times and the most potent compound against BChE (compound 7k) was 40.5-times more potent than galantamine. Docking study demonstrated that the most potent compounds interacted with main components of the active sites of AChE and BChE. Molecular dynamics of the most potent compounds showed that these compounds formed stable complex with target enzymes AChE and BChE. The most potent compounds also had acceptable pharmacokinetic properties as oral agents.

Degree-based topological indices, quantum computational, molecular docking and biological evaluations of o-nitroacetanilide

In this current work, the solute–solvent, electron behavior, wave function, and biological properties of o-nitroacetanilide were computed using a B3LYP/6–311++G(d,p) set. The spectroscopic characterization of ONA has been observed using UV–Vis correlated with the TD-SCF method in the IEFPCM model, which interpreted gas and polar, non-polar solvents. The energy gap values are explored through gas, DMSO and benzene, which describes less stability, more reactivity and best biological activity of the ONA. The stable optimized structure was estimated with topological (ELF, LOL, and RDG) properties determined using wave function to predict electron density and non-covalent interaction of the bio-molecular ONA chemical structure. The MEP surface plot was used to predict the reactivity sites of nucleophilic attack and electrophilic attack in gas and various solvents. The drug-likeness of the title compounds have been determines their potential for bioavailability through Lipinski Rule of five. The degree-based topological indices are used to describe physiochemical parameters to predict biocomponents. Finally, the biological uses of ONA were discovered through antimicrobial analysis. Molecular docking examines the protein–ligand interaction and stability of the title molecules targeted by the anti-cancer activity receptors 4CG9 and 4CGA, which exhibit −5.63 and −5.25 kcal/mol of ONA, respectively. The theoretical evaluation may enable chemists and pharmaceutical professionals to forecast the medication qualities without need for experimental testing and time-consuming towards future perspective.

Design and synthesis of new benzothiazole-piperazine derivatives and in vitro and in silico investigation of their anticancer activity

In this work, novel benzothiazole-piperazine acetamide (2a-2l) analogs were synthesized and evaluated their anticancer activity. The 1HNMR , 13CNMR and LC-MS/MS spectral data and elemental analyses were used to clarify the structure of the final molecules. The title compounds were procured by reacting 2‑chloro-N-(6-substituted benzothiazole-2-yl) acetamide with some piperazine derivatives. Cytotoxicity and apoptosis parameters including Annexin V binding capacities, effect on cell cycle, caspase-3 activation and mitochondrial membrane depolarization effect were evaluated to determine anticancer profile of the final molecules on A549 (human lung adenocarcinoma), C6 (glioma cell line) and NIH/3T3 (mouse embryoblast cell line). Mostly, the final molecules showed significant cytotoxic profile with prominent selectivity. 2c (IC50: 7.23±1.17, SI: 6.93), 2d (IC50: 17.50±4.95; SI: 11.59), and 2 h (IC50: 10.83±0.76; SI: 29.23) showed significant and selective cytotoxic activity. Compounds 2b, 2c and 2e provoked apoptosis of A549 cells with potential higher than cisplatin as determined by flow cytometry. The cell cycle analysis of 2b, 2e, 2 g, and 2 h suggested that the A549 cells were affected during G0/G1 phase. Caspase-3 activation was observed on cells by compounds 2a, 2e, 2i and 2l at most. The highest mitochondrial membrane depolarization ratios were seen treated by compounds 2e, 2 h, and 2j. None of the analogs displayed any obvious inhibition activity on MMP-9. The physicochemical properties were predicted for all compounds and also molecular docking and dynamics simulation studies were realized for compound 2e, namely N-(6-methoxybenzothiazol-2-yl)-2-(4-(p-tolyl) piperazin-1-yl) acetamide. The results indicated that merging benzothiazole and piperazine derivatives via acetamide bridge is promising in cancer research because these moieties can interact with the loop and ß-sheet regions of MMP-9. So, 2e was considered as a potential therapeutic agent against lung carcinoma.

Investigation of antibacterial and antifungal properties of benzene sulfonamide derivatives by experimental and computational studies

This study investigates the antibacterial and antifungal properties of eight benzene sulfonamide derivatives synthesized and reported in our previous study using a combination of experimental and computational methods. In antimicrobial activity, the MIC values of all the eight tested compounds were approximately 125.00 μg/mL against eight bacterial and three fungal strains. However, the compound 8 was found to exhibit remarkable activity (MIC=31.25 μg/mL) against E. faecalis (bacteria) and C. parapsilosis (fungi) compared to the MIC values of rest of the compounds. Results of in-silico drug-likeness and pharmacokinetic (ADMET) assessment reveal that all the title compounds met the compliance of criteria of drug-likeness rules and exhibited zero violations across. Results of docking study demonstrates that the compound 8 showed the highest binding affinity (-8.7 kcal/mol) among the compounds against S. aureus TyrRS, whereas against S. aureus DHFR, compound 2 exhibited the highest binding afinity of -8.5 kcal/mol. Among the compounds docked against C. albicans DHFR and C. albicans N-myristoyl transferase, compound 8 demonstrated the highest binding affinity of -8 kcal/mol and -8.9 kcal/mol, respectively. The results of antibacterial and antifungal experiments substantiate the predictions made by computational studies and provide empirical evidence of antibacterial and antifungal potential of the reported benzene sulfonamide derivatives.

Novel benzoyl and acetyl pyrazine-2-carbohydrazonamide hybrid derivatives: Experimental and theoretical insights

A series of novel benzoyl and acetyl pyrazine-2-carbohydrazonamide hybrid derivatives, namely N’-benzoylpyrazine-2-carbohydrazonamide (1), N’-(4-methylbenzoyl)pyrazine-2-carbohydrazonamide (2), N’-(2-phenylacetyl)pyrazine-2-carbohydrazonamide (3) and N’-(2-(1H-indol-3-yl)acetyl)pyrazine-2-carbohydrazonamide (4), were readily obtained using a metallic Na-assisted interaction of 2-cyanopyrazine with benzohydrazide, 4-methylbenzohydrazide, 2-phenylacetohydrazide or 2-(1H-indol-3-yl)acetohydrazide in dry MeOH. Compounds 1–4 were studied by a set of physical measurements, including FTIR, 1H NMR and UV–vis spectroscopy, while their crystal structures were elucidated by single crystal X-ray diffraction and the corresponding crystal packing was further studied in detail using the Hirshfeld surface analysis. Compounds 3 and 4 were found to adopt both the E- and Z-isomeric forms in DMSO‑d6. Molecules of the title compounds are linked via NH⋯O and NH⋯N hydrogen bonds and π⋯π interactions, yielding supramolecular aggregates. As it was found by the Hirshfeld surface analysis, molecules of 1–4 mainly interact through the H⋯X (X = H, C, N and O) and C⋯X (X = C and N) contacts. The molecular interactions were quantified and compared using DFT calculations, molecular electrostatic potential (MEP) analysis and quantum theory of atoms in molecules (QTAIM) analysis, highlighting the dominant role of hydrogen bonding interactions in governing the crystal packing.

Synthetic Approaches to and Structures of Diplatinum Polyynediyl Complexes trans,trans‐[(C6F5)(R3P)2Pt(C≡C)nPt(PR3)2(C6F5)] With Odd Numbers of Triple Bonds;Avoiding Complicating Ethynediyl Extrusions

Reactions of trans‐(C6F5)(p‐tol3P)2Pt(C≡C)nSiEt3 (PtC2nSi; n = 5, 7, 9) and ex­cess PtCl in the presence of wet n‐Bu4N+ F– (to effect protodesilylation) under Sonogashira‐type conditions (CuCl, base, other additives) afford the title compounds PtC10Pt, PtC14Pt, and PtC18­Pt in 42‐32% yields. A four‐fold substitution of the phosphine ligands in PtC10Pt by PEt3 affords Pt'C10Pt' (78%), and a Sonogashira reaction of Pt'C2H and Pt'Cl affords Pt'C2Pt' (68%). The analogous reaction with PtC2Si and PtCl is unsuccessful, presumably for steric reasons. The cryst­al structures of PtC10Pt, PtC14Pt, Pt'C10Pt', and Pt'C2Pt' exhibit a number of interesting trends and features. Certain sp chain extension reactions that lead to or employ the precursors PtC10Si, PtC12Si, PtC14Si, and PtC18Si sometimes give byproducts derived from C2 loss, and possible origins are discussed. Related phenomena have been reported by others in the course of synthe­sizing extended conjugated polyynes.

Design of new α-glucosidase inhibitors based on the bis-4-hydroxycoumarin skeleton: Synthesis, evaluation, and in silico studies

In this work, we have reported the design, synthesis, in vitro, and in silico enzymatic evaluation of new bis-4-hydroxycoumarin-based phenoxy-1,2,3-triazole-N-phenylacetamide derivatives 5a-m as potent α-glucosidase inhibitors. All the synthesized analogues showed high inhibition effects against α-glucosidase (IC50 values ranging between 6.0 ± 0.2 and 85.4 ± 2.3 µM) as compared to the positive control acarbose (IC50 = 750.0 ± 0.6 µM). Among the newly synthesized compounds 5a-m, 2,4-dichloro-N-phenylacetamide derivative 5i with inhibition effect around 125-folds more than the acarbose was identified as the most potent entry. A structure–activity relationship (SAR) study about the title compounds 5a-m demonstrated that the inhibition effects of these compounds depend on the pattern of substitution on the N-phenylacetamide ring. The interaction modes and binding energies in the active site of enzyme of the important analogues (in term of SAR study) were evaluated through molecular docking study. Molecular dynamics and prediction of pharmacokinetic properties and toxicity of the most potent compound 5i also evaluated and the obtained data was compared with the acarbose.

Encapsulating Nickel-Iron Alloy Nanoparticles in a Polysilazane-Derived Microporous Si-C-O-N-Based Support to Stimulate Superior OER Activity.

The in situ confinement of nickel (Ni)-iron (Fe) nanoparticles (NPs) in a polymer-derived microporous silicon carboxynitride (Si-C-O-N)-based support is investigated to stimulate superior oxygen evolution reaction (OER) activity in an alkaline media. Firstly, we consider a commercial polysilazane (PSZ) and Ni and Fe chlorides to be mixed in N,N-dimethylformamide (DMF) and deliverafter overnight solvent reflux a series of Ni-Fe : organosilicon coordination polymers. The latter are then heat-treated at 500 °C in flowing argon to form the title compounds. By considering a Ni : Fe ratio of 1.5, face centred cubic (fcc) NixFey alloy NPs with a size of 15-30 nm are in situ generated in a porous Si-C-O-N-based matrixdisplaying a specific surface area (SSA) as high as 237 m2 ⋅ g-1. Hence, encapsulated NPs are rendered accessible to promote electrocatalytic water oxidation. An OER overpotential as low as 315 mV at 10 mA ⋅ cm-2 is measured. This high catalytic performance (considering that the metal mass loading is as low as 0.24 mg cm-2) is rather stable as observed after an activation step; thus, validating our synthesis approach. This is clearly attributed to both the strong NP-matrix interaction and the confinement effect of the matrix as highlighted through post mortem microscopy observations.

Synthesis of 2‐Aminopyridine Derivatives via a Tandem CuAAC/Ring‐Cleavage/[4+2]‐Cycloaddition/Rearrangement Reaction Sequence

Abstract2H‐Azirines are an important class of small‐ring heterocycle that have been employed as versatile synthetic building blocks. Herein, a one‐pot CuAAC/ring‐cleavage/[4+2]‐cycloaddition/rearrangement reaction sequence involving terminal ynones, sulfonyl azides and 2H‐azirines is reported that leads to 2‐aminopyridine derivatives. In the first step, highly reactive N‐sulfonyl α‐acylketenimines are generated, via a CuAAC/ring‐cleavage process, from sulfonyl azides and terminal ynones and these undergo inverse electron‐demand Diels–Alder cycloaddition reactions with 2H‐azirines to form (isolable) 1,3‐oxazines that themselves undergo base‐promoted ring‐cleavage and rearrangement reactions to afford the title compounds.

Mer-[Ni(dien)2]Cl2.H2O and mer-[Ni(dien)2](NO3)2 complexes (dien= diethylenetriamine): Synthesis, physical, computational studies, antioxidant activity, and their use as precursors for Ni/NiO nanoparticles’ preparation

Two new Ni(II) complexes, mer-[Ni(dien)2]Cl2.H2O (I) and mer-[Ni(dien)2](NO3)2 (II), where dien= diethylenetriamine and mer refers to meridional coordination, have been prepared under ambient conditions. Complex (I) crystallizes in the P21/c space group of the monoclinic system, with a = 13.5000(4) Å, b = 8.7170(3) Å, c = 13.9430(4) Å, β = 102.091(2)° and V = 1604.41 Å3, whereas complex (II) crystallizes in the Pbca space group of the orthorhombic system, with a = 8.8117(6) Å, b = 14.0023(8) Å, c = 26.7603(17)Å and V = 3301.79 Å3. Both structures contain the [Ni(C4H13N3)2]2+ cation, together with two chloride anions and a water molecule for (I) and two nitrate anions for (II). The metal centre is coordinated to six nitrogens of the neutral dien ligands in a slightly distorted octahedral geometry. The two compounds have been characterised by FTIR and UV-Vis spectroscopy. Their morphology and size were studied by scanning electron microscopy (SEM). The thermal behaviour of the title compounds was also investigated. Calcination of the two complexes in air yielded Ni/NiO nanoparticles. The structures of both complexes were optimised and their simulated geometric parameters and vibrational modes were discussed and correlated with the experimental data. The antioxidant potential of both complexes was evaluated using DPPH, ferric reducing power tests and phosphomolybdenum assay.

Synthesis, structure, theoretical calculation and photocatalytic property of a novel Mn(II) supra-molecular compound containing SCN- and 2,2′-bipyridine ligands

A novel supra-molecular compound [Mn(SCN)2(byp)2] 1 (byp = 2,2′-bipyridine) was synthesized under hydrothermal conditions. Noteworthily, the SCN- in the title compound is derived from the in situ reaction of salicylaldehyde thiosemicarbazone. X-ray single-crystal diffraction analysis shows compound 1 is only a mononuclear structure, but it is expanded into a 3D supramolecular structure via H-bonds and π···π stacking. Hirshfeld Surface analysis shows C⋯H, H⋯H and S⋯H interaction are the main contribution of intermolecular interactions in the formation of compound 1. All of title compounds were characterized by IR spectroscopy, elemental analysis, XRD, XPS and TG analysis. The energy framework of compound 1 is dominated by dispersion interaction. The photocatalytic degradation ability of compound 1 for methylene blue is verified by photocatalytic degradation experiments (pH = 4: 44.6 %; pH = 7: 76.2 %; pH = 10: 78.8 %). Furthermore, the potential photocatalytic mechanism of compound 1 is inferred by UV–vis absorption spectra and Mott–Schottky curve.

Synthesis, Characterization and Energetic Properties of Hydroxymethyl-Bishomocubanone Derivatives.

The present work reports synthesis, characterization and theoretical insights on novel hydroxymethyl-bishomocubanone derivatives. Twelve new bishomocubanes (BHCs) were synthesized and fully characterized by various spectroscopic techniques and single crystal X-ray analysis. The densities of the title compounds were in the range of 1.30-1.59 g/cm3. Density-functional theory (DFT) based calculations at B3LYP/6-311++G(d,p) level of theory were performed on ten selected BHC based cage compounds. Propulsive and ballistic properties of newly synthesized hydroxymethyl-bishomocubanone derivatives in solid and liquid propulsion systems were calculated, and the results suggested that these compounds are superior to conventional fuel RP1 and binder HTPB. The detonation parameters revealed that these compounds are not explosive in nature and safe to use as solid propellants. Furthermore, kinetic and thermal stabilities of the title compounds were determined by HOMO-LUMO energy gap, ESP maps, impact sensitivity (h50) and bond dissociation energies (BDEs) followed by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Three compounds, a dinitroazide (Isp,vac=310.98 s), a dinitrate (Isp,vac=309.51 s), and a dinitronitrate (Isp,vac=309.20s) were found to be excellent candidates for volume limited applications.