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The development of novel and environmentally friendly solvents for chemical reactions is a vital in the pursuit of sustainable chemistry. This study presents a sustainable and efficient protocol for the rapid oxidation of benzaldehyde derivatives in the presence of catalytic Deep Eutectic Solvent (DES) system to their corresponding benzoic acids. A novel ternary DES composed of Urea/ZnCl2/HCl was synthesized using a combination of Urea, ZnCl2, and HCl for the first time and employed as an environmentally friendly oxidation catalyst using H2O2 as an oxidant at 60 °C. Benzaldehyde derivatives with diverse range of functional groups and substitution patterns afforded remarkable results, as it achieved high to excellent yields of the corresponding benzoic acids within a remarkably short reaction time of only 50 min. This protocol offers several advantages over alternative methods, including high product yields, the elimination of toxic and hazardous solvents and catalysts, and straightforward experimental procedures. Furthermore, the synthesized DES excellent recyclability, allowing for its reuse up to five times without any significant loss of functionality. Moreover, the synthesized DES demonstrated exceptional recyclability, enabling it to be reused up to five times without experiencing any notable decline in its effectiveness or functionality.

Eurotium is the teleomorph genus associated with the section Aspergillus. Eurotium comprises approximately 20 species, which are widely distributed in nature and human environments. Eurotium is usually the key microorganism for the fermentation of traditional food, such as Fuzhuan brick tea, Liupao tea, Meju, and Karebushi; thus, Eurotium is an important fungus in the food industry. Eurotium has been extensively studied because it contains a series of interesting, structurally diverse, and biologically important secondary metabolites, including anthraquinones, benzaldehyde derivatives, and indol diketopiperazine alkaloids. These secondary metabolites have shown multiple biological activities, including antioxidative, antimicrobial, cytotoxic, antitumor, insecticidal, antimalarial, and anti-inflammatory activities. This study presents an up-to-date review of the phytochemistry and biological activities of all Eurotium species. This review will provide recent advances on the secondary metabolites and their bioactivities in the genus Eurotium for the first time and serve as a database for future research and drug development from the genus Eurotium. [ABSTRACT FROM AUTHOR]

Abstract Three new Schiff bases, (Z)-2-(4-(dimethylamino)benzylidene)-N-methylhydrazinecarbothioamide (PDM), (Z)-2-(2-hydroxy-5-nitrobenzylidene)-N-methylhydrazinecarbothioamide (5NS) and (Z)-2-(4-cyanobenzylidene)-N-methylhydrazinecarbothioamide (4CN) of thiosemicarbazone-benzaldehyde derivatives were synthesized by condensation reaction. These compounds were formed from the reaction of 4-methyl-3-thiosemicarbazide with p-dimethylaminobenzaldehyde, 5-nitrosalicylaldehyde and 4-formylbenzonitrile respectively. The molecules synthesized were screened against bacterial isolates; Gram-positive (Staphylococcus aureus and Bacillus cereus), and Gram-negative (Klebsiella pnuemoniae and Pseudomonas aeruginosa) bacteria using agar well diffusion technique, supported by molecular docking and theoretical analysis through computational approach adopting a coupled DFT-B3LYP and 6-31G(d) basis set. The in-vitro antibacterial studies proofed that the compounds have a broad-spectrum antibacterial activity against the bacterial isolates while 5NS (21.0 mm) and PDMA (9.5 mm) have higher antibacterial activities than the standard drug, streptomycin against Staphylococcus aureus (16.5 mm) and Pseudomonas aeruginosa (9.0 mm) respectively. Theoretical studies and molecular docking established the fact that these Schiff bases could be explored further as bioactive compounds against bacterial infections and also as corrosion inhibitors of metals in the oil and gas industry. Graphical abstract

In this study, mono‐ or poly‐methoxylated phenyl boronic acids, were subjected to Rieche formylation. Unexpectedly the corresponding ipso‐substituted aryl aldehydes were obtained in excellent yields and, for some of these substrates, the formylated arylboronic acids were also synthesized in moderate yields. These findings provide new insights into the general reactivity and versatility of arylboronic acids. [ABSTRACT FROM AUTHOR]

Eurotium is the teleomorph genus associated with the section Aspergillus. Eurotium comprises approximately 20 species, which are widely distributed in nature and human environments. Eurotium is usually the key microorganism for the fermentation of traditional food, such as Fuzhuan brick tea, Liupao tea, Meju, and Karebushi; thus, Eurotium is an important fungus in the food industry. Eurotium has been extensively studied because it contains a series of interesting, structurally diverse, and biologically important secondary metabolites, including anthraquinones, benzaldehyde derivatives, and indol diketopiperazine alkaloids. These secondary metabolites have shown multiple biological activities, including antioxidative, antimicrobial, cytotoxic, antitumor, insecticidal, antimalarial, and anti-inflammatory activities. This study presents an up-to-date review of the phytochemistry and biological activities of all Eurotium species. This review will provide recent advances on the secondary metabolites and their bioactivities in the genus Eurotium for the first time and serve as a database for future research and drug development from the genus Eurotium.

The development of novel and environmentally friendly solvents for chemical reactions is a vital in the pursuit of sustainable chemistry. This study presents a sustainable and efficient protocol for the rapid oxidation of benzaldehyde derivatives in the presence of catalytic Deep Eutectic Solvent (DES) system to their corresponding benzoic acids. A novel ternary DES composed of Urea/ZnCl 2 /HCl was synthesized using a combination of Urea, ZnCl 2 , and HCl for the first time and employed as an environmentally friendly oxidation catalyst using H 2 O 2 as an oxidant at 60 °C. Benzaldehyde derivatives with diverse range of functional groups and substitution patterns afforded remarkable results, as it achieved high to excellent yields of the corresponding benzoic acids within a remarkably short reaction time of only 50 min. This protocol offers several advantages over alternative methods, including high product yields, the elimination of toxic and hazardous solvents and catalysts, and straightforward experimental procedures. Furthermore, the synthesized DES excellent recyclability, allowing for its reuse up to five times without any significant loss of functionality. Moreover, the synthesized DES demonstrated exceptional recyclability, enabling it to be reused up to five times without experiencing any notable decline in its effectiveness or functionality. [ABSTRACT FROM AUTHOR]

Endophytic Aspergillus species represent an inexhaustible source for many medicinally important secondary metabolites. The current study isolated the endophytic Aspergillus niger (OL519514) fungus from Opuntia ficus-indica fruit peels. The antibacterial activities were reported for both Aspergillus species and Opuntia ficus-indica fruit peel extract. Extraction of the endophytic fungal metabolites using ethyl acetate and fractionation was performed, yielding dihydroauroglaucin (C1), isotetrahydroauroglaucin (C2), and cristatumin B (C3). Resistant bacterial strains were used to investigate the efficiency of the total fungal ethyl acetate extract (FEA) and the isolated compounds. FEA showed promising wide spectrum activity. (C3) showed excellent activity against selected Gram-negative resistant bacteria; However, (C2) exhibited tremendous activity against the tested Gram-positive resistant strains; conversely, (C1) possessed the lowest antibacterial activity compared to the two other compounds. An in silico virtual molecular docking demonstrated that cristatumin B was the most active antimicrobial compound against the selected protein targets. In conclusion, the active metabolites newly isolated from the endophytic fungus Aspergillus niger (OL519514) and present in plants' waste can be a promising antimicrobial agent against multidrug-resistant bacteria. [ABSTRACT FROM AUTHOR]

This paper reports the use of rhodium (Rh) catalysts for the oxidative coupling reaction between phenylacetylene and benzaldehyde derivatives via C-H bond activation. These reactions were catalyzed by Rh(l-amino acid)(cod) (the l-amino acid is l-phenylalanine, l-valine or l-proline; cod is 1,5-cyclooctadiene) to obtain chromones in 12.7–88.3% yield. These new Rh catalysts have excellent activity for the coupling reaction between phenylacetylene and different benzaldehyde derivatives. It was found that the electronic effects of the benzaldehyde derivative substituent affected the reaction yield, which is in accordance with the proposed mechanism.

Endophytic Aspergillus species represent an inexhaustible source for many medicinally important secondary metabolites. The current study isolated the endophytic Aspergillus niger (OL519514) fungus from Opuntia ficus-indica fruit peels. The antibacterial activities were reported for both Aspergillus species and Opuntia ficus-indica fruit peel extract. Extraction of the endophytic fungal metabolites using ethyl acetate and fractionation was performed, yielding dihydroauroglaucin (C1), isotetrahydroauroglaucin (C2), and cristatumin B (C3). Resistant bacterial strains were used to investigate the efficiency of the total fungal ethyl acetate extract (FEA) and the isolated compounds. FEA showed promising wide spectrum activity. (C3) showed excellent activity against selected Gram-negative resistant bacteria; However, (C2) exhibited tremendous activity against the tested Gram-positive resistant strains; conversely, (C1) possessed the lowest antibacterial activity compared to the two other compounds. An in silico virtual molecular docking demonstrated that cristatumin B was the most active antimicrobial compound against the selected protein targets. In conclusion, the active metabolites newly isolated from the endophytic fungus Aspergillus niger (OL519514) and present in plants’ waste can be a promising antimicrobial agent against multidrug-resistant bacteria.

Two benzaldehyde derivatives, flavoglaucin (1) and isotetrahydro-auroglaucin (2), were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-κB (NF-κB) activation by suppressing phosphorylation of IkappaB (IκB). These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-κB pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1) expression through the nuclear transcription factor-E2–related factor 2 (Nrf2) translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-κB binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP). Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression.

A facile and useful method for synthesis of benzalazines was introduced in this work. The reaction of synthesis of the relevant azines is carried out in the presence of acetonitrile-H2O2/(NH4)2CO3 without using hydrazine. This reaction affords symmetrical azines in excellent yields with high purity. Products were characterized by the Common techniques (infrared, ¹H NMR and melting point). [ABSTRACT FROM AUTHOR]

ABSTRACT The benzaldehyde derivatives, such as 2,4-dimethoxy benzaldehyde (PC1) and p-anisaldehyde (PC2), were successfully used as photoredox catalysts (PCs) in combination with typical RAFT agent 4-cyano-4-(phenylcarbonothioylthio)pentanoic acid (CTP) for the controlled photoinduced electron transfer RAFT polymerization (PET-RAFT) of methyl methacrylate (MMA) and benzyl methacrylate (BnMA) at room temperature. The kinetics of the polymerizations showed first order with respect to monomer conversions. Besides, the average number molecular weights ( Mn) of the produced polymers increased linearly with the monomer conversions and kept relatively narrow polydispersity (PDI = Mw /Mn). For example, the Mn of PMMA increased from about 3400 to 17,300 g mol−1 with the increasing in monomer conversion from 11% to 85%, and the PDI maintained around 1.36. The living features of polymerizations with the PC1 and PC2 as catalysts have also been further supported by chain extension and synthesis of PMMA- b-PBnMA diblock copolymer. As a result, the simplicity and efficiency of benzaldehyde derivatives catalyzed PET-RAFT polymerization have been demonstrated under mild conditions. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 229-236 [ABSTRACT FROM AUTHOR]

Green synthesis is the design of chemical products and processes that reduces or eliminates the use and generation of hazardous substances. Schiff bases of 4-hydroxy-3- methoxybenzaldehyde (vanillin) were prepared using various aromatic amines and base catalyst in the presence of aqueous media. High performance liquid chromatography (HPLC) and ultraviolet (UV) spectrophotometry methods were developed for qualitative study of the synthesized 4-hydroxy-3- methoxybenzaldehyde Schiff bases. HPLC was carried out by reversed phase on a C18 column with a mobile phase composed of acetonitrile and 0.5% triethyl amine (pH 4.5 adjusted with orthophosphoric acid (60:40, v/v)). UV measurements were performed at λ 286 nm for compound V1 ((E)-4-(4-hydroxy-3-methoxybenzylideneamino)benzoic acid), λ 336 nm for compound V2 ((E)-4-(4-hydroxy-3-methoxybenzylideneamino)phenol), and λ 320 nm for compound V3 ((2-methoxy-4-(E)-(phenylimino)methyl)phenol). Both the HPLC and UV methods showed good reproducibility and precision and were successfully applied to study 4-hydroxy-3- methoxybenzaldehyde derivatives. The standard de-viations of relative peak area and retention times for 4-hydroxy-3-methoxybenzaldehyde derivatives were within 2% indicating the suitability of the system. The proposed economical methods can be applied for rou-tine analysis of 4-hydroxy-3-methoxybenzaldehyde derivatives of any type. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design of Strontium doped anisotropic TiO 2 nanomaterials. • The presence of Sr-O-Ti and Ti3+ entities enhances photogenerated charges storage. • The presence of Ov results in better selectivity to oxidation of benzaldehyde derivatives. The development of photocatalysts for selective esterification of aldehydes under visible light ''solar refinery" is greatly promising to solve the environmental and energy issues. Herein, key points were highlighted for the photo-assisted oxidation of benzaldehyde derivatives onto Sr-loaded TiO 2 nanotubes facilitating the selectively aromatic aldehydes conversion to ester under visible light irradiation. Herein, strontium loading was investigated in a 0.2–1.0 wt%. Various spectroscopy techniques such as X-ray diffraction, N 2 adsorption–desorption measurements, scanning electron microscopy coupled with energy-dispersive X-ray analysis, transmission electron microscopy, Raman, UV–vis diffuse reflectance, X-ray photoelectron and photoluminescence spectroscopies were used to fully characterize our samples. Our findings demonstrated that up to a Sr loading of 0.4 wt%, the addition of strontium induces an in-situ formation of high amount of oxygen vacancies Ov and Ti3+ entities on the surface of xSr-TiNT samples. However, the formation of segregated SrO species was observed when excess Sr loading was used. Photo-assisted oxidation of benzaldehyde derivatives occurs through competitive oxidation/reduction routes in the presence of photogenerated electron-hole pairs. Controlling the percentage of Ov provides a suitable tuning of the oxidation ability of photogenerated holes, avoiding over reduction to toluene and leading to a high selectivity into ester. Kinetically, oxygen vacancies induced by Sr acts as trap for photogenerated electrons. Moreover, the yield in ester increases following the Hammett constant, the highest yield being obtained for 2-hydroxybenzaldehyde (σ = -0.37). [ABSTRACT FROM AUTHOR]

In the work discussed in this paper, a series of novel benzaldehyde derivatives containing 1,3,4-thiadiazole were prepared in high yield from 4-fluorobenzaldehyde and 2-amino-5-substituted-1,3,4-thiadiazole. The products were characterized by determination of melting point, elemental analysis, and UV-visible, IR, H NMR, and C NMR spectroscopy. The fluorescence properties of the compounds were also studied by recording their fluorescence emission spectra. [ABSTRACT FROM AUTHOR]

IR-Fourier spectra of solutions and crystals of biologically active benzaldehyde derivatives were studied. Specific features of the formation of intra- and intermolecular hydrogen bonds were analyzed. Spectral signatures that characterized participation of the hydroxyl OH group and also the OCH 3 and C=O groups in the formation of intramolecular hydrogen bonds of the three different types O–H···O–H, O–H···O–CH 3, and O–H···O=C were revealed. Intramolecular hydrogen bonds of the types O–H···O–H and O–H···O–CH 3 were absent for benzaldehyde derivatives in the crystal phase. Only hydroxyl and carbonyl groups participated in intermolecular interactions. This resulted in the formation of linear intermolecular dimers. Seven various configurations of the linear dimers were identified in solutions and crystals. [ABSTRACT FROM AUTHOR]

The effect of some benzaldehyde derivatives on the corrosion of zinc in 0.5 M HCl solution is studied in this article using mass loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques. The percentage inhibition efficiency (%In) was found to increase with increasing concentration of the inhibitor and with decreasing temperature. Polarization studies indicated that all of the compounds studied are mixed-type inhibitors. The inhibitive action of these benzaldehyde derivatives has been discussed in view of the adsorption on the zinc surface. The adsorption process follows Temkin's isotherm. The addition of KSCN, KI, and KBr to benzaldehyde derivatives has enhanced the inhibition efficiency because of synergistic effect. The mechanism of inhibition process is discussed in the light of the chemical structures of the investigated inhibitors. [ABSTRACT FROM AUTHOR]

In a new multicomponent reaction phenanthridine reacts with isocyanides and malonitrile in the presence of benzaldehyde derivatives to produce 2-aryl-3-(alkyl- or arylimino)-2,3-dihydropyrrolo[1,2- f]phenanthridine-1,1(12b H)-dicarbonitrile in a simple, mild, and efficient protocol in excellent yields. Graphical Abstract: [MediaObject not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A method is proposed for the benzylation of secondary heterocyclic amines with functionalized derivatives of benzaldehyde in the presence of formic acid under conditions close to amination according to the Leuckart-Wallach reaction. [ABSTRACT FROM AUTHOR]

A group of 18 benzaldehyde derivatives was characterized as a family of mixed type inhibitors on the oxidation of l-3, 4-dihydroxyphenylalanine (l-DOPA) catalyzed by Sacrophaga neobelliaria phenoloxidase (PO), presumably by forming a Schiff base with a primary amino group of the enzyme. Inhibition constants and IC50 were determined. Cuminaldehyde was the most active inhibitor with an IC50 of 0.0067 mM. Vanillin was the least active inhibitor with an IC50 of 38 mM. Four physicochemical descriptors were identified by stepwise multiple regressions as significant predictors on the inhibition activity, which were further rotated by principle component analysis yielding two significant principle properties. It was shown that hydrophobicity of the substituent at the para position of the aldehyde group played major role on inhibition activity: one unit increase in Hansch–Fujita π value of the substituent led to about 4.5 [95% confidence interval is (7.9, 2.6)] fold increase on IC50. Electron-donating effect of the substituent at the para position of the aldehyde group was less important than hydrophobicity. Hydroxyl group at the ortho position of the aldehyde group contributed to higher inhibition activity, presumably by forming a quasi-six-membered ring with the unshared pair of electrons on the nitrogen atom of the amino group through intramolecular hydrogen bonding. [Copyright &y& Elsevier]

Desulfovibrio simplex spec. nov. strain XVI was isolated from an anaerobic sour whey digester. Single cells had a vibrioid shape and were motile by a single, polar flagellum. The size of cells was 0.5-1.0 μ×1.5-3.0 μm. The G+C content of the DNA of D. simplex strain XVI was 47.5 mol%. The only other Desulfovibrio species with a similar G+C content of the DNA was Desulfovibrio salexigens (46.1 mol%. D. simplex grew on H/CO, formate, pyruvate, L(+)-lactate, fumarate, malate, ethanol, 1-propanol and 1-butanol as electron donors, while Desulfovibrio salexigens grew in addition on methanol, 2-propanol, 2-butanol, glycerol, succinate, citrate, choline and glucose. Electron acceptors for D. simplex were sulfate, thiosulfate and nitrate. L(+)-Lactate was incompletely oxidized to acetate and CO during sulfate reduction. Furthermore, both species could be distinguished by the ability of D. simplex but not of D. salexigens to grow on and to oxidize benzaldehyde derivatives to the respective acids, including vanillin, p-anisaldehyde and syringaldehyde. Moreover, D. simplex could grow in the presence of trace amounts of NaCl, while D. salexigens had an obligate requirement of 25 g/l NaCl. In addition, D. simplex can be distinguished from D. salexigens by its differing polyamine pattern. On the basis of the presented data the description of strain XVI as Desulfovibrio simplex spec. nov. is proposed. [ABSTRACT FROM AUTHOR]

The acid-resistant and colorless thickener which were printed on the wool contained 4-Hydroxybenzaldehyde( PHBA) or 3, 4-dihydroxybenzaldehyde( MSDS) at acidic condition. According to the chromaticity value (a*'), the influence of different concentration of PHBA and MSDS can be judged. Then the factors such as mass fraction and time that affected the coloration were studied. The experiments indicated that the MSDS was more active to react with the protein fiber. Further more, the wool can be colored even the dosage of MSDS was low and under the low condition. Experiments showed that the color was bright yellow, with high washing and rubbing fastness as well as comfortable handle. [ABSTRACT FROM AUTHOR]

Two new benzaldehyde derivatives, 6-ethyl-2-hydroxy-4-methoxy-3-methylbenzaldehyde ( 1), 6-ethyl-2,4-dihydroxy-3-methylbenzaldehyde ( 2), together with 2, 4-dihydroxy-3,6-dimethylbenzaldehyde ( 3) were isolated from mangrove fungus (No. ZZF 32#) from the South China Sea. The structures of compounds 1 and 2 were established by comprehensive analysis of the spectral data, especially 2D NMR spectral results. [ABSTRACT FROM AUTHOR]