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The metal complexes of Azo dye; 4,4'-((methylene bis(3,l-phenylen)) bis (diazene-l,2-diyl)) bis(1,3-Benzenediol) are produced from 4,4`- methylenedianiline and Resorcinol were synthesized and characterized by using several analytical and spectral techniques. The ligand and its complexes were characterized by many chemo-physic methods like NMR, IR, UV-Vis, molar conductance measurement, analytical measurement, and melting point. The conditions of optimal reaction (for instance reagent concentration, pH etc) were studied and the analytical figures of merit such as limit of detection, linearity, sensitivity etc) were obtained.

Abstract: 10,11-Dehydrocurvularin is a natural benzenediol lactone (BDL) with a 12-membered macrolide fused to a resorcinol ring produced as a secondary metabolite by many fungi. In this review, we summarized the pieces of literature regarding biosynthesis, chemical synthesis, biological activities, and assumed work mechanisms of 10,11-dehydrocurvularin, which presented a potential for agricultural and pharmaceutical uses.

Sorbents utilizing organic molecules as Cs+-selective ionophores have increasingly gained attention over the years as the need for stable and reusable materials became ever more apparent with the poor performance of inorganic sorbents in acidic and alkaline aqueous environments. Aside from this, organic molecules offer a great degree of flexibility in terms of structure, function, and performance which can be harnessed for sorbent development. As such, various kinds of organic ligands have been employed for sorbent preparation, which include macrocycles like calixarenes and crown ethers, and acyclic molecules like tetraphenylborate and resorcinol formaldehyde. In this review, organic-based sorbents and ligands for Cs+ are described and compared, and the mechanisms underlying their efficacy for Cs+ sequestration are discussed. Improvements to ligand and sorbent development are proposed to address issues on adsorption selectivity, capacity, and material reusability. Moreover, a platform for the preparation of stimuli-responsive ligands and sorbents is presented.

A resorcinarene is a synthetic macrocycle consisting of four resorcinol molecules covalently linked by methylene bridges. The interannular bridges produce a cavitand that has a bowl-shaped structure. We have developed supramolecular capsules through Ag(I) or Cu(I) coordination-driven self-assembly of cavitands possessing 2,2′-bipyridyl arms in their upper rims. The self-assembled capsules accommodate various molecular guests and supramolecular assemblies possessing acetoxy groups. The host–guest chemistry of the molecular capsules has been applied in the fabrication of supramolecular polymers. This account describes recent developments in the supramolecular chemistry of resorcinarene-based coordination capsules and provides a brief history of resorcinarene-based capsules and related capsules.

High-pressure polymorphs can be obtained and stabilized at ambient pressure by utilizing dopants with more voluminous molecules, inducing internal strain in the structures. This effect has been confirmed for doped resorcinol and imidazole derivatives by nucleating and stabilizing their high-pressure phases under ambient conditions. The dopant molecular volume and concentration, as well as the bulk modulus of the polymorph in the binary system, are related to the stability region in the single-component phase diagram. High-pressure isothermal and isochoric recrystallizations yielded pure single crystals of resorcinol ε above 0.20 GPa and a new polymorph ζ above 0.70 GPa. These recrystallizations of pure resorcinol revealed within 1 GPa of the p–T phase diagram the boundaries and the stability regions of four resorcinol polymorphs α, β, ε, and ζ, contrary to the compression experiments on ambient-pressure polymorphs α and β, when the high-pressure phases were hidden behind the wide hysteresis extending to nearly 5 GPa. The hysteresis, originating from the H-bonding networks, hinders the formation of polymorphs ε and ζ when polymorphs α and β are compressed without melting or dissolving the crystals. Polymorph ζ is the only known resorcinol structure built of hydrogen-bonded layers.

Polymeric textile cords, steel cords and steel cables are mainly reinforcing materials that are used in tire production. Polymeric textile cords such as Polyester (PEs), Nylon, Aramid and Rayon are commonly treated with bi-functional resorcinol formaldehyde latex (RFL) to obtain desired adhesion to rubber matrix. PEs cords are known as their poor adhesion to both RFL and rubber compounds due to limited reactivity on the surface and poor reaction extent between methylol and hydroxyl groups of RFL. Increasing carboxyl content on PEs surface or in the rubber compound is one of the best strategies to overcome this adhesion problem. Liquid rubbers, which can co-vulcanize with solid rubbers, are also strong alternatives of process oils with their excellent plasticizing effect without deterioration in mechanical properties of the resulting material. Co-vulcanization also improves the stability of this additive and prevents possible bleeding and migration during service life of the tire. In this study, carboxylated grafted liquid isoprene rubber has been incorporated to rubber compound to improve adhesion in PEs-RFL-Rubber ternary system. Rheological and dynamic-mechanical properties of reactive liquid rubber containing tire rubber compounds have been evaluated extensively, as well as H-adhesion behaviour of PEs cord-rubber composite matrix.

Resorcinol (1,3-dihydroxybenzene) is a common coupling agent in permanent hair dyes, and has arrested people's attention for its potential hazard to human health. However, the action mechanism of resorcinol and human DNA has not been elucidated. In this research, the binding properties between resorcinol and calf thymus DNA (ct-DNA) were studied for the first time through various spectral and molecular docking techniques. Spectral studies showed that the initial fluorescence quenching of resorcinol against DNA was a static one. The result of ΔH 0 was produced from thermodynamic experimental data, therefore it could be concluded that electrostatic force was the major driving force, while binding constant Kb was 1.56 × 104 M-1 at 298 K. The electrostatic binding network between resorcinol and ct-DNA was established explicitly through competitive substitution analysis and other spectral approaches. The results of FT-IR absorption spectra indicated that resorcinol had bound to the DNA phosphate skeleton. Molecular docking clearly revealed that binding occurred between hydroxyl groups of resorcinol and phosphorus oxygen bonds (P-O) of the DNA skeleton. These findings may deepen our understanding of the action mechanism between resorcinol and ct-DNA and provide some useful data on the effect of resorcinol on human diseases.

The transformation of phenol, resorcinol, pyrocatechol, and hydroquinone in water at concentrations of 10–4 to 10–6 M under short-term exposure to UV radiation was studied by fluorescence analysis and high-performance liquid chromatography. It was found that resorcinol is transformed by the action of UV radiation more readily than the other compounds. It was shown that the main products from the photolysis of phenol are pyrocatechol and dihydroxybiphenyls. Resorcinol, pyrocatechol, and hydroquinone form trihydroxybenzenes.

A procedure for the preparation of an adduct of levoglucosenone and resorcinol was developed involving ultrasonic irradiation in the presence of K2CO3 and 18-crown-6 ether in toluene. In vitro anticoagulant and antiplatelet activity of the adduct was studied.

Bu çalışmada, 5-Metil-4-(2-tiazolilazo)-resorsinolün spektroskopik ve elektrokimyasal davranışı üzerindeki yüzey aktif madde etkileri, nötr pH'ta sulu bir çözeltide incelenmiştir. Araştırmada dodesilpiridinyum klorür (DDPC), setilpiridinyum klorür (CPC) (katyonik), Triton X100, Tween 20 (noniyonik) ve sodyum dodesil sülfat (SDS) (anyonik) kullanılmıştır. Yüzey aktif maddenin eklenmesi üzerine boyarmaddenin absorpsiyon maksimumunda büyük bir kırmızıya kayma gözlendi. Boyanın elektrokimyasal indirgenmesi döngüsel voltametri (CV) ile araştırıldı. Boyarmaddenin adsorpsiyon kontrollü indirgeme reaksiyonu, CPC ilavesiyle -0,43 V'de yarı-tersinir difüzyon kontrollü bir indirgeme pikine dönüştü. Boyarmadde çözeltisindeki CPC konsantrasyonuna bağlı olarak elektrot reaksiyonunun pik potansiyeli katodik yönde yaklaşık 120 mV kaydı ve pik akımı on kata kadar düştü. Bu değişiklikler, çözeltideki yüzey aktif maddenin tipine ve konsantrasyonuna bağlı olarak yorumlandı.

Considering numerous issues due to asphaltene precipitation during production and transportation of crude oil, this work aims to postpone the onset point of asphaltene and improve the stability of its colloids in heavy (S) and light oil (D) samples. For this purpose, water/oil interfacial tension (IFT) is measured to evaluate the effect of surfactants as asphaltene inhibitor on heavy and light oil samples from Iranian south fields. Onset of precipitation from oil samples is revealed by sudden change in IFT between deionized water and oil samples through addition of different fractions of n-heptane as precipitant. Surfactants are used to stabilize the asphaltene colloids and prevent asphaltene precipitation from crude oil. However, crude oils of different properties require investigations for appropriate surfactant at optimum concentration to delay asphaltene precipitation. In this work, three surfactants Linear dodecyl-benzene-sulfonic acid (L–DBSA), dodecyl resorcinol (DR) and nonylphenol (NP) are examined for their retarding capabilities of onset point of asphaltene precipitation in oil samples S and D. Also, the involved mechanisms for addition of surfactant to crude oil are analyzed and interpreted. Enhanced stability of crude oil and degree of postpone in onset point follows the order of L–DBSA > DR > NP for heavy oil S and NP > DR > L–DBSA for light oil D owing to nature and chemical structure of surfactants and also properties of crude oil samples. Furthermore, IFT fluctuations for light and heavy oil are similar but the faster onset point and different values of IFT for light oil arise from unstable nature and density difference.

In current paper, adsorbents based on silica L 40/100 modified with 4-(2-pyridylazo)resorcinol, 1-(2-pyrylazo)naphthol‑2, pyrocatechol violet and sodium N, N‑diethyldithiocarbamate were obtained. Adsorbents were modified by non-covalent immobilization of organic analytical reagents on the silica surface. It is noted that the preparation of such adsorbents is fast and easy to manufacture. The conditions of Bismuth (III) adsorption from dilute aqueous solutions by the proposed adsorbents are studied and optimized. The optimal values of the medium acidity for the effective Bismuth (III) preconcentration by the proposed adsorbents based on silica modified with organic analytical reagents have been established. It is shown that the use of modified silicas allows efficient (95–98%) removal of Bismuth (III) from dilute aqueous solutions. Under optimal adsorption conditions, the capacity of modified adsorbents is determined. It is established that the modification of silica leads to a significant (2–3 times) increase in the capacity of the obtained sorbents by Bismuth (III) in comparison with the unmodified silica, which is associated with the processes of complexation on the surface. The desorption of Bismuth (III) from the surface of unmodified and modified silicas by solutions of mineral acids has been studied. It is shown that Bi(III) is quantitatively desorbed from the surface of unmodified silicas by solutions of sulfuric and nitric acids, and in the case of modified silicas the degree of desorption is small and does not exceed 35%. The data obtained can then be used to develop a test system for determination of Bismuth (III) via corresponding colorimetric scales or for quantitative solid phase extraction and adsorption-spectroscopic quantification of Bismuth (III) in some real samples.

A novel enhanced oil recovery (EOR) method based on polymer gel-assisted carbon dioxide (CO2) huff and puff was developed aiming to improve the development effect of heavy oil reservoirs with high water cut. The polymer gel prepared using partially hydrolyzed polyacrylamide (HPAM), hexamethylenetetramine, phenol, resorcinol, oxalic acid, and thiocarbamide as raw materials had a special network structure to overcome the challenge of significant heterogeneity in heavy oil reservoirs. The strength of polymer gel reached the maximum value 20,000 mPa·s within 22 h. The temperature resistance and salt resistance of polymer gel directly determined the plugging effect. The polymer gel was placed for 190 days at 85 ℃, and its apparent viscosity retention rate was 66.4%. The salt resistance experiments showed that the apparent viscosity retention rate of this polymer gel at 1.8 wt % NaCl, 0.045 wt % CaCl2, 0.045 wt % MgCl2 was 71.3%, 78.5%, 71.4%, respectively. Huff and puff experiments confirmed that this method could be used to increase the sweep volume and improve the oil displacement efficiency of heavy oil reservoirs with high water cut. Furthermore, the EOR of this method was better than that of water huff and puff, polymer gel huff and puff or CO2 huff and puff.

Organic resorcinol formaldehyde (RF) aerogel was synthesized via the sol–gel process. The synthesized RF aerogel was modified by the incorporation of 1 and 3 wt.% of amine-functionalized graphene oxide (GO) during the synthesis process to prepare RF-GOA. The FTIR results showed that the functionalization of aerogels with amine was successfully conducted. The FESEM images showed that the interconnected 3D porous structure was created in the modified samples GO plates without affecting the porosity of the structure. The UV–Vis results showed that the RF-GOA1 and RF-GOA3 have improved the elimination amounts of antibiotics from 51 to 77% for oxytetracycline and from 65 to 94% for chlortetracycline. The absorption capacity for the neat RF aerogel, RF-GOA1, and RF-GOA3 was determined to be 258, 387, and 278 mg/g for oxytetracycline antibiotics and 326, 472, and 467 mg/g for the chlortetracycline antibiotics, respectively. Optimal pH for RF aerogel, RF-GOA1, and RF-GOA3 was obtained to be 6, 4, and 2 for oxytetracycline and 4, 2, and 6 for chlortetracycline, respectively. In addition, the adsorption data for modified aerogels were suited by the pseudo-second-order model, and the results showed that chemical adsorption was involved in the rapid absorption of antibiotics on modified aerogels.

A simple photoreduction method was used to deposit Au nanoparticles (Au NPs) at different loadings (0.1–2 Au%) into mixed phase brookite-anatase titanium dioxide (TiO2) nanowires (NWs). X-ray diffraction (XRD) verified that the Au/TiO2 NWs were composed of a mixture of brookite (84.24%) and anatase (15.76%); while transmission electron microscopy (TEM) showed a uniform dispersion of 5- to 10-nm Au NPs over the TiO2 NWs. The photocatalytic performance of the synthesized Au/TiO2 NWs was evaluated for the degradation of resorcinol under UVA illumination. The 0.1% Au/TiO2 NWs photocatalyst offered the best photocatalytic efficiency for resorcinol degradation among the synthesized samples, with the rate, constantly increasing from 0.0014 to 0.003 min−1 after adding 0.1% Au into TiO2 NWs. At Au higher loadings, the rate decreased (0.0005 min−1 for 2% Au/TiO2 photocatalyst. The enhanced activity of the 0.1% Au/TiO2 NWs sample could be ascribed to the effective electron–hole separation at brookite/anatase phase junctions. The Au/TiO2 NWs has maintained good activity over five catalytic test cycles.

A method for the preparation of polycondensed chromeno[2,3-b]chromenes was developed based on the formal [3+3] cycloaddition reaction between 1H-benzo[f]chromene-2-carbaldehydes and 2-naphthols. In the case of resorcinol, the bisannulation product formed with the participation of both hydroxy groups was isolated.

Regular injections of insulin provide life-saving benefits to millions of diabetics. Apart from native insulin and insulin analogue formulations, microcrystalline insulin suspensions are also commercially available. The onset of action of the currently available basal insulins relies on the slow dissociation of insulin hexamers in the subcutaneous space due to the strong binding of small organic ligands. With the aim of identifying insulin–ligand complexes with enhanced pharmacokinetic and pharmacodynamic profiles, the binding affinity of two resorcinol-based molecules (4-chlororesorcinol and 4-bromoresorcinol) and the structural characteristics of insulin upon co-crystallization with them were investigated in the present study. `In solution' measurements were performed via saturation transfer difference (STD) NMR. Co-crystallization upon pH variation resulted in the production of polycrystalline precipitates, whose structural characteristics (i.e. unit-cell symmetry and dimension) were assessed. In both cases, different polymorphs (four and three, respectively) of monoclinic symmetry (P21 and C2 space groups) were identified via X-ray powder diffraction. The results demonstrate the efficiency of a new approach that combines spectroscopy and diffraction techniques and provides an innovative alternative for high-throughput examination of insulin and other therapeutic proteins.

This work spotlights on the rapid and effective separation method for the no-carrier-added (NCA) 47Sc from natural irradiated Ti target using an anionic exchanger resin; AN-31 impregnated with 4-(2-Pyridylazo) resorcinol (PAR). The newly prepared resin (An-PAR) was characterized by FTIR and SEM. The Influence of pH on the distribution coefficients (Kd) of Sc(III) and Ti(IV) ions was investigated by batch technique and the results revealed that Ti(IV) ions are strongly adsorbed by AN-PAR rather than AN-31, while Sc(III) ions are weakly adsorbed on the both resin materials. The radiochemical separation of 47Sc(III) from irradiated natural Ti target was successfully carried out, where the elution efficiency for 47Sc reached 89 ± 1.5% with high radiochemical, radionuclidic and chemical purities. Our findings thus hold a great promise for the use of 47Sc radioisotope in the preparation of radiopharmaceuticals for theranostics applications.

Catalyst-free and solvent-free three-component tandem approach can synthesize 2-amino-4H-chromene scaffolds by Knoevenagel–Michael cyclocondensation of aryl aldehydes, malononitrile, and resorcinol via visible light irradiation as a green promoter at room temperature. The significant advantages of the present protocol include energy-effectiveness, catalyst-free, excellent yields, solvent-free, operational simplicity, and high atom-economy, commercially accessible inexpensive preliminary substances, so it meets some features of sustainable and green chemistry.

Application of a dynamic covalent chemistry strategy to the reversible reaction system of resorcinol and α, ω-alkanedials [(CH2)m(CHO)2] (m = 2–10) in ethanol in the presence of hydrogen chloride (...

The present study reports the effective solid-state preparation of CuInSe2/NiFe2O4 nanocomposites by simple MOF-assisted synthesis at moderate temperatures. The as-synthesized CuInSe2/NiFe2O4 nanocomposites were systematically analysed to evaluate their structural and morphological features using XRD, SEM, and HRTEM. The photocatalytic performances of the CuInSe2/NiFe2O4 nanocomposites were evaluated for the degradation of two endocrine disruptors namely, bisphenol-A and resorcinol. The photocatalytic performances revealed that the CuInSe2/NiFe2O4 nanocomposite enabled a higher removal rate of bisphenol-A and resorcinol under visible light. The generated (°OH) and holes (h+) played a major role in CuInSe2/NiFe2O4 nanocomposites by the removing of aqueous bisphenol-A and resorcinol. In addition, CuInSe2/NiFe2O4 photocatalysts could be easily separated from treated wastewater by using an external magnetic field and they were easily recycled, making them an ideal candidate for environmental remediation. Here, CuInSe2/NiFe2O4 nanocomposites were prepared for the first time by coupling MOF-derived NiFe2O4 with CuInSe2 in the solid-state, route was reported for the first time. From the experimental results and degradation studies, we proposed photocatalytic mechanisms for improving CuInSe2/NiFe2O4 nanocomposite photocatalytic performance. The well-organized heterostructure effect and effective separation of photoinduced charge carriers between NiFe2O4 and CuInSe2 enabled faster degradation. The synthesized recyclable CuInSe2/NiFe2O4 nanocomposite has been applied as an alternative photocatalyst material in the treatment of both households and various industrial pollutants.

The competitive hydrogenation and hydrodeoxygenation (HDO) of dihydroxybenzene isomers, catechol (1,2-dihydroxybenzene), resorcinol (1,3-dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene), was studied in the liquid phase over a Rh/silica catalyst at 323 K and 3 barg hydrogen pressure. Under competitive hydrogenation conditions an order of reactivity of ortho > para > meta was observed. Catechol initially inhibited resorcinol and hydroquinone hydrogenation but not HDO suggesting separate sites for hydrogenation and HDO. When resorcinol and hydroquinone were reacted competitively, HDO became the favoured reaction. The data suggested that cyclohexane and cyclohexanone were primary products. At low dihydroxybenzene (DHB) conversion the ratio of HDO products was dependent upon DHB isomer. When all three DHB isomers were reacted together, initially 86% of the HDO yield came from catechol with the rest from hydroquinone. When resorcinol finally reacted, HDO products were produced first. Reaction of DHB isomers in pairs using deuterium instead of hydrogen revealed changes in kinetic isotope effect (KIE). The presence of competing reactants had a dramatic effect on the energetics of hydrogenation and HDO reactions of individual components, reinforcing the view that hydrogenation and HDO are mechanistically separate. This effect on reaction energetics observed when more than one substrate was present, highlights the limitations of studying one single model compound as a route to understanding the processes required for the upgrading of a true bio-oil feed.

A flame-retardant agent, resorcinol bis(diphenyl phosphate) (RDP), was synthesized with resorcinol, phenol and phosphorus oxychloride under a catalytic action of magnesium chloride. Synthesized RDP was applied to cotton fabrics with a bridging agent of urea-formalin resin (UFR) to endow them with flame retardancy. The vertical flammability tests were performed, revealing that cotton fabrics treated with 25% RDP and 15% UFR could exhibit the most reasonable flame retardancy. Here, other properties of cotton fabrics, such as mass increment, color change, resistance to washing and hand feeling, were found to be almost unspoiled. The suitable heat-treating condition for temperature and duration was determined to be 160 °C and 2 min. The results of scanning electron micrography, energy dispersive X-ray and Fourier transform infrared spectroscopy showed that RDP was strongly bonded to cotton fiber with a successful bridging action of UFR. Thermogravimetric analysis confirmed that the coated cotton fabrics possessed flame retardant properties.

BACKGROUND Melasma has a complex pathogenesis, and various aggravating factors contribute to its recalcitrance to treatments. A combination of isobutylamido thiazolyl resorcinol (ITR) and hyaluronic acid (HA) could increase melasma treatment efficacy. AIMS To compare the efficacy and safety of 0.15% ITR plus HA vs 0.15% ITR or HA alone in melasma treatment. METHODS Ninety-two patients received ITR 0.15% plus HA (n = 30), 0.15% ITR (n = 31), or HA (n = 31) along with broad-spectrum sunscreen application for 12 weeks. Treatment efficacy was determined using modified Melasma Area Severity Index (mMASI), average melanin and melanin variation with Antera3D® , and safety based on transepidermal water loss. RESULTS Compared with the HA group, the ITR+HA group showed significantly reduced mMASI at weeks 4, 8, and 12 (p = 0.026, 0.015, and 0.001, respectively), whereas the ITR group showed a significant reduction at week 12 (p = 0.027). There was no significant difference in the mMASI or average melanin level between the ITR+HA and ITR groups. Melanin variation was significantly lower in the ITR+HA group than in the ITR group at weeks 4, 8, and 12 (p = 0.027, 0.019, and 0.023, respectively). CONCLUSIONS The combination of 0.15% ITR and 0.15% ITR+HA effectively reduced melasma severity. HA could synergistically improve melasma homogeneity.

In this work, four time-saving, economic, and non-sophisticated spectrophotometric methods are used to determine resorcinol (RES) and catechol (CAT) in their binary solutions. The suggested methods...

A facile two-step method including hydrothermal reaction and activation at high temperature was designed to prepare nitrogen doped copolymer derived carbon materials with melamine(M) as nitrogen source and resorcinol(R)-furfural(F) resin as carbon precursor. The melamine not only introduces nitrogen in the copolymer-based carbon materials but also tunes the pore structure of the obtained samples. The as-prepared nitrogen-rich carbon materials (RMFC-3.6) possess an ultra-high specific surface area of 2572.33 m2 g−1 with ideal channel structure and nitrogen content up to 1.40 wt.%. RMFC-3.6 exhibits excellent adsorption capacity and fast adsorption rate for most dyes. Using Congo red (CR), Rhodamine B (RhB) and Malachite green (MG) as waste water pollutant models, the maximum adsorption capacities of CR, Rh B and MG reached 3207.61, 2947.42 and 5769.23 mg g−1, respectively, much higher than the reported values. Moreover, the adsorption process of RMFC-3.6 has a good correlation with Langmuir isotherms and coincides with pseudo-second-order kinetic models. Significantly, the adsorption capacity retention of RMFC-3.6 for CR after four cycles maintains 93.17%, indicating excellent cycling stability.

A new cocrystal of Vitamin D3 (Cholecalciferol) and resorcinol has been discovered and characterized through experimental cocrystal screening. Its high stability has been studied against light, hea...

A procedure was developed for preparing resorcinolpyromellitein [3,3,7,7-tetrakis(4-hydroxy-2,2ʹ-oxydiphenyl)pyromellitide] by acylation of resorcinol with pyromellitic dianhydride using tin tetrachloride as a catalyst (120–210°С, 30 h, reactant ratio pyromellitic dianhydride : SnCl4 : resorcinol = 1.0 : 2.5 : 5.0). The structure of the target product was proved by elemental analysis, thin-layer chromatography, UV and IR spectroscopy, 1H NMR spectroscopy, differential scanning calorimetry, and high-performance liquid chromatography with mass-spectrometric detection. The synthesized product exhibits increased hydrophilicity and imparts fluorescence properties to aqueous solutions when dissolved in a small amount (5 × 10–4 wt %), which allows it to be recommended as a chemical marker in tracer exploration of oil strata at oil fields.

Magnetic solid phase microextraction (m-SPME) is a well-defined strategy for the preconcentration and separation of hydrophobic species from aqueous samples without the use of toxic organic solvents. This work identifies a new analytical procedure for trace level vanadium(V) by inductively coupled plasma mass spectrometry coupled to magnetic solid phase microextraction. The procedure is based on the preconcentration of the V(V)–H2O2–4-(2-pyridylazo)resorcinol complex. Magnetic Fe3O4 nanoparticles decorated multi-walled carbon nanotubes as an adsorbent were investigated systematically. The calibration curve obtained by using m-SPME for vanadium(V) was linear from 0.011 to 10 µg/L. The method detection limit was found to be 1.5 ng/L. The m-SPME method was applied to the assay of vanadium in a certified reference water sample and the result was in total balance with the declared value. Finally, the proposed method was applied to the determination of vanadium in real water samples.

Sol-gel processing combined with soft templating and gelation-induced phase separation is very sensitive to the precursor sol composition. In this work we present a straightforward synthesis towards hierarchically structured, macroporous carbon/titania monoliths with ordered mesopores derived from resorcinol/formaldehyde monoliths and a glycolated titanium precursor. We demonstrate the influence of various reaction solvents, where diol-based media and the proportion of the catalyst seem to be essential in controlling spinodal decomposition, obtaining similar monolithic structures under different synthesis conditions. Based on these observations, we further homogeneously incorporated TiO2 into the carbon structure by an in situ synthesis approach, obtaining structural features similar to pure carbon materials with surface areas of about 400 m2 g-1 , periodically arranged mesopores with a mean distance of 10-11 nm and cellular macroporosity.

Heteropolymeric materials of resorcinol, aniline, urea, and formaldehyde are synthesized by 1:1:1:3 molar ratios of the respective monomers with different percentages of hydrophilic bentonite via a mixed condensation polymerization in an aqueous acidic media. The heteropolymeric material and heteropolymeric/hydrophilic bentonite were characterized by Fourier transform FT-IR spectroscopy and UV–Vis absorption spectra. The surface morphology of heteropolymer composites was recorded at various magnification powers by SEM which revealed well-defined granular spherical morphology of variable size in the range of 0.220 μm to 1.370 μm. Moreover, small pieces of bentonite were inserted and distributed through the field with different particle sizes. They cumulated and condensed in certain zones forming some plaques of different sizes. The heteropolymeric material is soluble in most of the organic solvents including, THF, DMF, and DMSO. It is also dissolved in concentrated HNO3. The new synthesized heteropolymeric material was examined as an antimicrobial agent. The current procedure introduces an inexpensive and eco-friendly approach for developing new heteropolymer composites acquiring the requested new functionality.

The stability of metal-organic frameworks is a key factor in many applications in some fields that require working under harsh conditions. It is known that a large number of MOFs are vulnerable to humid air. It means that when they are exposed to water, a structural collapse of the crystal happens. In this work, Molecular Dynamics simulations using a reactive force field have been performed to study the stability of MOF-74 against the adsorption of catechol, resorcinol and hydroquinone in the presence of water. We reproduced the water instability of Zn-MOF-74 and we studied the resistance of the structure. Our simulations showed that the three isomers generate a volume change in the framework but the structural collapse does not happen. In contrast, for water-isomer mixtures, there is structural collapse. Not only do catechol, resorcinol and hydroquinone not behave as stabilizing agents but they do enhance the hydration effect on the structure.

Herein, in this study, we utilized Ag+-ligand interactions for critically regulating the morphology of carbon by the Stober-silica/carbon co-assembly method for the first time. Tetraethyl orthosilicate (TEOS) and resorcinol/formaldehyde (RF) assemble upon dictation by Ag+ and pyridyl-functionalized surfactants, producing porous carbon tubes (RF1) with a high surface area of 696 m2 g-1 and accessible mesopores ∼15 nm in size. Furthermore, when using tetrapropyl orthosilicate (TPOS) with a slower hydrolysis rate than that of TEOS, carbon tubes (RF2) with enhanced uniformity and a surface area as high as 2112 m2 g-1 are generated. Additionally, when using dopamine hydrochloride instead of RF as a carbon precursor, tubular polydopamine (TDA) with lengths of tens of microns is fabricated, which exhibits excellent catalytic activity toward oxygen reduction reactions in alkaline solutions due to its unique structural feature, a high surface area of 1350 m2 g-1, metallic silver remains of 8.3 wt%, and a rich nitrogen content of 3.6 wt%. This work sheds light on the engineering of a micellar soft template and synthesizing novel nanostructures by the extension of the Stober method.

A hybrid material reduced graphene oxide based organic nanocomposite was synthesized from graphite by modified Hummers method, which is further chemically reduced to form reduced graphene oxide (rGO) and with resorcinol through a solvothermal process a reduced graphene oxide-resorcinol (rGO-R) nanocomposite was obtained. The synthesized materials surface morphology and structural compositions were studied through X-ray diffraction (XRD) and scanning electron microscope (SEM) and their optical properties were studied through UV-visible spectroscopy and photoluminescence. The material was further used as a fluorescent chemosensor to detect cerium ion under aqueous conditions. The rGO-R composite's sensing abilities were studied by following parameters viz. pH, reversibility, time and the interference of other probable competing ions. The sensing follows both the photo-induced electron transfer and intramolecular charge transfer processes. © 2021 Chemical Publishing Co.. All rights reserved., Department of Science and Technology, Ministry of Science and Technology, India, डीएसटी: SERB-EMR/2016/005692

An efficient method for the synthesis of benzannelated macrocyclic di- and triperoxides by cyclocondensation of phenol, catechol, resorcinol or hydroquinone with bis-hydroperoxides and formaldehyde in the presence of lanthanide catalysts has been developed. Additionally, by using flow cytometry, it has been shown for the first time in this work that thus-synthesized macrocyclic di- and triperoxides are efficient apoptosis inducers in the tumor cultures Jurkat, K562 and U937 and in fibroblasts.

Sandwich 12·2, macrocyclic 1·3 and box 12·42 supramolecular assemblies were synthesized by the reaction of 1,8-bis(4-pyridylethynyl)anthracene 1 with hydroquinone 2, resorcinol 3 and 1,5-dihydroxynaphthalene 4via hydrogen-bonding interactions, respectively. The formed sandwiches, macrocycles and boxes can further self assemble to form a double-layer supramolecular polymer, nanotubes and a one-dimensional “iron chain type” supramolecular polymer. Investigation of their crystal structures revealed that the distance between two oxygen atoms in a hydrogen bonding donor play an important role in the formation of supramolecular assemblies.

We developed two fast, simple and sensitive spectrophotometric methods for the determination of ceftazidime in drugs by using phenolic reagents resorcinol and 2-methylphenol. The methods are based on a previous antibiotic diazotization in the medium of hydrochloric acid (CHCl=12 M) and its following azo coupling with reagents in an alkaline medium with the formation of effective analytical forms that allow determining ceftazidime and have maximum absorbance at 519 nm and 516 nm for resorcinol and 2- methylphenol, respectively. The azo coupling products of diazotized ceftazidime exhibit effective molar absorptivity in the range of (6.31–6.84)103 M–1 cm–1. Stoichiometric ratios of the azo compounds components were established using continuous variations methods and they were the same in both cases (1:1). The developed methods allow determining from 2.75 to 185.5 g mL–1 of ceftazidime with resorcinol (LOQ=2.54 g mL–1) and 0.32191.3 g mL–1 of ceftazidime with 2-methylphenol (LOQ=0.28 g mL–1). The developed methods have been successfully tested in the analyses of one-component preparations (powders for injection solutions).

The Kane-Maguire polymerization mechanism is disassembled at a molecular level by using DFT-based quantum mechanical calculations. Resorcinol electropolymerization is selected as a case study. Stationary points (transition states and intermediate species) leading to the formation of the dimer are found on the potential energy surface (PES), and elementary reactions involved in the dimer formation are characterized. The latter allow to further propagate the polymerization chain reaction, when applied recursively. In this paper, the fundamental role of the sulfate anion (a typical base electrolyte) is addressed. Investigation of the PES in terms of both stationary-state properties and of ab initio molecular dynamics results (dynamic reaction coordinate) allows the appreciation in detail of the critical role of the base electrolyte anion in making the proton dissociation from the initial radical ion, a feasible (downhill in energy) process.

The bark of Swietenia machrophylla is colored dark red, and it is correlated with the extractives constituents such as phenolic compounds. This study, therefore, aims to investigate extractives from the inner and outer bark of S. machrophylla and their effects to color properties. The results showed that the extractive content in the inner bark was higher than the outer except for hot water solubles. In addition, the polyphenols and sugar levels from inner to outer bark were increased, except in the soluble-sugar of hot water extractive. The highest correlation between the absorbance of methanol, hot water-soluble extracts, and total polyphenols were observed using the visual spectrophotometer. The extractives that contributed to the bark's color were indicated from flavonoids with a precursor such as monophenol of catechol and resorcinol.

Objectives Topical resorcinol 15% is a self-treatment for painful hidradenitis suppurativa nodules and abscesses with good results in reducing pain and lesion duration. The aim of this study is to establish a 15% topical resorcinol formula, to develop a physicochemical and microbiological stability study and to further determine the compounding shelf-life in different package conditions following the European Pharmacopoeia (Ph. Eur.) specifications. Methods Physicochemical and microbiological stability studies of the formulation were conducted for 12 months at room temperature (25°C±2°C) in different package conditions: aluminium tubes (aluminium A7-99.7% varnish DF-6172), plastic tubes (low density polyethylene) and amber plastic containers (polyethylene terephthalate). High performance liquid chromatography (HPLC) was developed as a method of indicating the stability of the resorcinol formulation. A microbiological growth assay was also validated according to the Ph. Eur. Physical properties were inspected to determine parameters such as odour, colour, pH, emulsion phase and extensibility index and its evolution. Results The HPLC method was validated according to the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. At day 365, visual inspection remained unchanged only for preparations packaged in aluminium tubes. The pH did not vary by more than 0.3 units in all conditions. The extensibility index decreased in the preparations packaged in plastic and amber plastic containers. HPLC analysis conducted over 1 year did not show a degradation greater than 7% of resorcinol in the preparation in plastic and aluminium packages. The ability of ATCC strains to grow in resorcinol formulation was confirmed under the suitability test. Resorcinol packed in aluminium tubes achieved microbiological stability at day 365. Conclusions Only the formulation package in aluminium tubes showed physicochemical and microbiological stability of resorcinol for 12 months at room temperature (25°C±2°C).

Chemical investigation of the Vietnamese plant Aegiceras floridum Roem. & Schult. (Primulaceae) led to the isolation of the new compound 3-methoxy-5-nonylphenol (1) along with five known ones 2,8,10-trihydroxy-6H-benzo[c]chromen-6-one (2), 2-hydroxy-5-methoxy-3-nonylbenzo-1,4-quinone (3), 5-(3-hydroxypropyl)-7-methoxy-3-(methylbenzofuran-2-yl)-3-methoxyphenol (4), 2,8-dihydroxy-7-methoxy-3,9-diundecyldibenzofuran-1,4-dione (5) and 10-hydroxy-4-methoxy-2,11-diundecylgomphilactone (6). The structures were elucidated by analysis of their HRESIMS and NMR data as well as the comparison of their NMR data with those reported in the literature. The cytotoxic activity of selected isolated compounds against some cancer cell lines such as human epithelial carcinoma (HeLa), human lung cancer (NCI-H460), liver hepatocellular carcinoma (HepG2), human breast cancer (MCF-7), and acute T cell leukemia (Jurkat) was evaluated. Among them, 3 showed moderate activities against MCF-7 with an IC50 of 17.77 µM and NCI-H460 with an IC50 of 25.02 µM. The result of DPPH radical scavenging activity assay indicated that compounds 2–4 and 6 revealed weak antioxidant activity.

It was found that the reaction of 2-hydroxy-5,7,8-trimethyl-2H-1,2-benzoxaphosphinine 2-oxide with resorcinol and its derivatives as well as sesamol leads to the formation of phosphaneoflavanones in high yields. The obtained phosphaneoflavanones are precursors in the synthesis of novel unsymmetrical cage phosphonates. The structures of the obtained products were confirmed by IR spectroscopy, 1H, 13C NMR spectroscopy, and X-ray structural analysis.

To explore the possibility of using a specially functionalized nanoemulsion for the removal of free radical, resveratrol and phenethyl resorcinol were employed to form resveratrol/phenethyl resorcinol mixed active components, and the removal efficiency of free radicals was evaluated. Original nanoemulsion and specially functionalized-nanoemulsion were characterized by DLS and EPR. The free radical scavenging ability of the mixed active components of resveratrol/phenethyl resorcinol was determined as a function of the mass ratio of resveratrol to phenethyl resorcinol, temperature, and ionic strength. In the results, the removal of free radicals by the resveratrol/phenethyl resorcinol nanoemulsion system was found to be more effective than the nanoemulsion alone. At a higher resveratrol ratio, more than 68% of free radicals could be removed. The efficiency was also found to increase with rising temperature. However, efficiency decreased with the increase in ionic strength. In conclusion, compared with conventional nanoemulsion, the combined utilization of nanoemulsion and the mixed active components of resveratrol/phenethyl resorcinol achieved better results for the removal of free radicals because of synergistic effect between nanoemulsion droplets and the mixed active components of resveratrol/phenethyl resorcinol, involving hydrophobic binding, hydrogen binding, and partitioning.

Metallic amphiphiles are used as building blocks in the construction of nanoscale superstructures, where the hydrophobic effects induce the self-assembly of the nanoparticles of interest. However, the influence of synergizing multiple chemical interactions on an effective design of these structures mostly remains an open question. In this regard, supraamphiphilic systems based on flexible surfactant molecules and rigid macrocycles are being actively developed, but there are few works on the interaction between metallosurfactants and macrocycles. In the present work, the self-assembly and biological properties of a metallosurfactant with calixarene were studied for the first time. The metallosurfactant, a complex between lanthanum nitrate and two 4-aza-1-hexadecylazoniabicyclo[2.2.2]octane bromide units, and calix[4]resorcinol containing sulfonate groups on the upper rim were used to form a novel supraamphiphilic composition. The system formed was studied using a variety of physicochemical methods, including spectrophotometry, NMR, XRF, and dynamic and electrophoretic light scattering. It was found that the most optimal tetraanionic calix[4]resorcinol to dicationic metallosurfactant molar ratio, leading to mixed aggregation upon ion pair complexation, is 2:3. The mixed aggregates formed in the pentamolar concentration range were able to encapsulate hydrophilic substrates, including the anticancer drug cisplatin, the pure form of which is more cytotoxic toward healthy cells than toward diseased cells. Interestingly, the drug loaded into the macrocycle-metallosurfactant particles was less cytotoxic to a healthy Chang liver cell line and more cytotoxic to tumor M-HeLa cells. This selectivity depends on the amount of cisplatin added. The more drug is added to the macrocycle-metallosurfactant composition, the greater the biological activity against cancer cells. Taking into account that the appearance of resistance of cancer cells to drugs, especially to cisplatin, is one of the most important problems in treatment, the results of this work envisage the potential application of a mixed macrocycle-metallosurfactant system for the design of therapeutic cisplatin compositions.

Chiral iodoarenes have been steadily increasing in importance in recent years, especially in enantioselective synthesis and catalysis. Since the development of the concept of chiral iodine(I/III) catalysis, the use of various chiral aryliodine frameworks has been explored in this area. This short review gives an overview of the use of chiral hypervalent iodine(I/III) reagents based on the 2-iodoresorcinol core with two attached two lactic side chains bearing ester or amide groups for the catalytic enantioselective dearomatization of phenol compounds, asymmetric oxidation of alkenes, and enantioselective α-functionalization of carbonyl compounds highlighting the excellent reactivities in terms of yield and enantioselectivity.1 Introduction2 Enantioselective Dearomatization of Phenol Derivatives3 Asymmetric Oxidation of Alkenes4 Enantioselective α-Functionalization of Carbonyl Compounds5 Conclusion and Outlook

Toward a sustainable synthesis of value-added chemicals, the method of CO2 utilization attracts great interest in chemical process engineering. Biotechnological CO2 fixation is a promising technology; however, efficient methods that can fix carbon dioxide are still limited. Instead, some parts of microbial decarboxylases allow the introduction of carboxy group into phenolic compounds using bicarbonate ion as a C1 building block. Here, we identified a unique decarboxylase from Arthrobacter sp. K8 that acts on resorcinol derivatives. A high-throughput colorimetric decarboxylase assay facilitated gene cloning of orsellinic acid decarboxylase from genomic DNA library of strain K8. Sequence analysis revealed that the orsellinic acid decarboxylase belonged to amidohydrolase 2 family, but shared low amino acid sequence identity with those of related decarboxylases. Enzymatic characterization unveiled that the decarboxylase introduces a carboxy group in a highly regio-selective manner. We applied the decarboxylase to enzymatic carboxylation of resorcinol derivatives. Using Escherichia coli expressing the decarboxylase gene as a whole cell biocatalyst, orsellinic acid, 2,4-dihydroxybenzoic acid, and 4-methoxysalicylic acid were produced in the presence of saturated bicarbonate. These findings could provide new insights into the production of useful phenolic acids from resorcinol derivatives.

Reactions of chiral nopinane-annulated diazafluorenone with substituted phenols and naphthols by the action of trifluoromethanesulfonic acid led to spiro products. The structure of the resorcinol derivative was confirmed by X-ray structural analysis.

The sol–gel synthesis of silica/carbon nanocomposite was modified with nickel in order to enhance the dispersion of silica nano-powder in the carbon matrix. The synthesized doped nanocomposite RF/SiO2-Ni5% (S-RF) is composed of carbon matrix based on resorcinol formaldehyde (RF) as observed in the X-ray diffraction patterns and by scanning electron microscopy characterization. The average sizes of the crystallite of the S-RF are presented in the 13–17 nm range. FTIR Spectroscopy analysis showed that the band at just about 1040 cm−1 is associated to vibrations of Si–O–Si. The addition of nickel improves the interaction between the matrix and the nanoparticles, which appears well at 1100 °C. Moreover, the influences of the doping of Ni in the S-RF nanocomposite were analyzed.

"The polymer blend of Chitosan: polyvinyl alcohol (PVA) (1:1) weight percent and hydroxyethyl cellulose (HEC) (0.5%) was prepared. The profile of the sample and its properties were measured by Fourier transfer Infrared spectroscopy (FTIR). The Scanning Electron Microscopy (FESEM) was used to describe the morphology of the polymer blend with two magnifications without any ratio of 4- (2-Pyridylazo) resorcinol monosodium salt hydrate and with 0.15 % of a 4-(2-Pyridylazo) resorcinol monosodium salt hydrate. The mechanical properties were demonstrated and characterized by Elongation and Young modulus. The polymer blend was incorporated with different weight ratios of 4-(2-Pyridylazo) of resorcinol monosodium salt hydrate, (0.03, 0.05, 0.07, 0.09, 0.15) gm of weight %. The current-voltage (I-V) characterization of prepared thin films showed ohmic behavior and the electrical conductivity was improved by increasing the ratio of dopant that leads all samples to reflect a semiconductor behavior.