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A simple, efficient and green protocol has been developed for the synthesis of polysubstituted dihydropyridines via one-pot, four-component reaction of aldehydes, arylamines, dialkyl acetylenedicarboxylate, and malononitrile. The reaction was proceeded at room temperature in the absence of catalyst in aqueous ethyl lactate under visible light irradiation. The main advantages of the present approach are mild reaction condition, high yield, no column chromatography, clean reaction profile, environmentally friendly and sustainable from the economic point of view

Objective: Aminomethylphenol molecules have wider applications in pharmaceuticals, agrochemicals, plant protection and promising functional materials. The development of an efficient and practical method to prepare this class of compound is highly desirable from both environmental and economical points of view. Materials and Methods: In order to establish an effective synthetic method for preparing aminomethylphenol derivatives, the Petasis borono-Mannich reaction of salicylaldehyde, phenylboronic acid and 1,2,3,4- tetrahydroisoquinoline was selected as a model reaction. A variety of reaction conditions are investigated, including solvent and temperature. The generality and limitation of the established method were also evaluated. Results and Discussion: It was found that model reaction can be carried out in cyclopentyl methyl ether at 80 °C under catalyst-free conditions. This protocol, with broad substrate applicability, the reaction of various arylboronic acid, secondary amine and salicylaldehyde proceeded smoothly under optimal reaction conditions to afford various aminomethylphenol derivatives in high yields. A practical, scalable, and high-yielding synthesis of aminomethylphenol derivatives was successfully accomplished. Conclusion: A catalyst-free practical method for the synthesis of minomethylphenol derivatives based on Petasis borono–Mannich (PBM) reaction of various arylboronic acid, secondary amine and salicylaldehyde in cyclopentyl methyl ether has been developed. The salient features of this protocol are avoidance of any additive/catalyst and toxic organic solvents, use of cyclopentyl methyl ether as the reaction medium, clean reaction profiles, easy operation, and high to excellent yield.

A magnetic CdS quantum dot (Fe 3 O 4 /PDA/CdS) was synthesized through a facile and convenient method from inexpensive starting materials. The characterization of the prepared catalyst was performed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), and vibrating sample magnetometer (VSM) techniques. The Fe 3 O 4 /PDA/CdS was found to be a highly active photocatalyst for amidation of aromatic aldehydes with amines using air as a clean oxidant under mild conditions. The prepared photocatalyst can be recovered by magnetic separation and successfully reused for 5 cycles without considerable loss of its catalytic activit.

A novel approach for the visible-light-initiated synthesis of 2-amino-4H-pyran-3,5-dicarbonitrile derivatives via a one-pot, three-component reaction of aldehydes or isatins, malononitrile, and α-cyano ketones has been developed. The reaction was carried out at room temperature in ethanol/water to give the corresponding products with a wide range of functional groups in high yields. This process did not require any additives or chromatographic separation and could be applied for gram-scale synthesis.

The application of natural eutectic solvent (NDDES) in organic synthesis has received more and more attention. In this work, a green protocol for one-pot synthesis of spiro[indoline-3,4′-pyrazolo[3,4-b]pyridines] via three-component reactions of 1H-pyrazol-5-amin, isatin and enolizable C H activated compound is achieved by the combination of microwave irradiation with choline chloride and lactic acid based NDDES. This novel method is clean, cheap, simple, high yield, chromatography-free and scalable. The use of choline chloride and lactic acid as a biodegradable, recycled and reusable media meets most of the criteria to be considered as a sustainable and environmentally benign process.

A simple calcination method has been developed to prepare potassium-doped carbon nitride (K-CN). The prepared K-CN was characterized and analyzed by fourier infrared spectroscopy (FT-IR), powder X-ray diffraction technology (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and other techniques. It has been proved to be a green and recyclable catalyst for Knoevenagel condensation of benzaldehydes with malononitrile. The reaction system has the characteristics of mild reaction conditions, simple operation, and environmental protection. The catalyst still maintains high catalytic activity and excellent chemical stability after being recycled for six times.

A series of near infrared absorption photothermal conversion polyurethane (PTPU) was synthesized with a cyanine dye to act as near infrared absorption component and polyethylene glycol 10,000 (PEG10000) to act as phase change material (PCM). The light resistant, pH dependence of dye and the effect of PEG10000 content on the properties of PTPU were investigated. The results showed that the cyanine dye had good light stability and was sensitive to pH, so a saturated solution of boric acid was added in the synthesis of PTPU to adjust its pH to 6 ~ 7. The crystalline degree of PTPU increased and its thermal stability decreased with the increasing of PEG10000 content; the light absorption of PTPU was mainly determined by the dye; the photothermal conversion efficiency and energy storage capability of PTPU increased with the increasing of PEG10000 and the PTPU can reach a higher temperature under illumination comparing to control polyurethane (PU); the PTPUs underwent a solid–solid phase change process and had excellent durability.

The dissociative anesthetic phencyclidine (PCP) and PCP derivatives, including 4&prime, F-PCP, are illegally sold and abused worldwide for recreational and non-medical uses. The psychopharmacological properties and abuse potential of 4&prime, F-PCP have not been fully characterized. In this study, we evaluated the psychomotor, rewarding, and reinforcing properties of 4&prime, F-PCP using the open-field test, conditioned place preference (CPP), and self-administration paradigms in rodents. Using Western immunoblotting, we also investigated the expression of dopamine (DA)-related proteins and DA-receptor-mediated downstream signaling cascades in the nucleus accumbens (NAc) of 4&prime, F-PCP-self-administering rats. Intraperitoneal administration of 10 mg/kg 4&prime, F-PCP significantly increased locomotor and rearing activities and increased CPP in mice. Intravenous administration of 1.0 mg/kg/infusion of 4&prime, F-PCP significantly enhanced self-administration during a 2 h session under fixed ratio schedules, showed a higher breakpoint during a 6 h session under progressive ratio schedules of reinforcement, and significantly altered the expression of DA transporter and DA D1 receptor in the NAc of rats self-administering 1.0 mg/kg 4&prime, F-PCP. Additionally, the expression of phosphorylated (p) ERK, pCREB, c-Fos, and FosB/&Delta, FosB in the NAc was significantly enhanced by 1.0 mg/kg 4&prime, F-PCP self-administration. Taken together, these findings suggest that 4&prime, F-PCP has a high potential for abuse, given its robust psychomotor, rewarding, and reinforcing properties via activation of DAergic neurotransmission and the downstream signaling pathways in the NAc.

An efficient and practical synthetic method has been developed for the facile synthesis of 1,2,4-trioxanes by the condensation of -hydroperoxy alcohols and carbonyl compounds in the presence of a catalytic amount of silica-supported FeCl3 (FeCl3/SiO2) at room temperature. The method has the benefits of operational simplicity, high yields and potentially large-scale application. Moreover, the catalyst can be readily recovered by simple filtration and reused up to five times with almost maintained its catalytic activity.

Oxalic acid and proline based deep eutectic solvent (DES) has been identified as an effective catalyst and environmentally benign reaction medium for one-pot synthesis of 13-aryl-13H-benzo[g]benzothiazolo[2,3-b]quinazoline-5,14-diones via three-component reaction of aromatic aldehydes, 2-aminobenzothiazole and 2-hydroxy-1,4-naphthoquinone under microwave irradiation. The reported approach shows significant advantages such as easy work-up, environment-friendly process, short reaction times, excellent yields, one-pot multicomponent reaction, chromatography-free purification, the recycling and the re-use of the DES.

A highly efficient, eco-friendly protocol has been developed for synthesis of spirooxindole-pyran derivatives via one-pot, three-component reaction of isatins, malononitrile, and enolizable C–H activated compounds (2-hydroxynaphthalene-1,4-dione, 4-hydroxycoumarine and dimedone) under visible-light irradiation in water-ethyl lactate at room temperature. The reported approach shows significant advantages such as a high yield, mild and clean reaction conditions, the application of clean visible light as a source of energy, the absence of catalyst, the use of ethyl lactate/water as an environmentally friendly solvent, a one-pot multicomponent reaction at room temperature, no chromatographic separation, and applicability for large-scale synthesis.

Magnetically separable graphene oxide supported molybdenum (Fe 3 O 4 /GO-Mo) nanoparticles were prepared and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and vibrating sample magnetometry (VSM) techniques. The synthesized heterogeneous material was found to exhibit high catalytic activity in one-pot, three-component reaction of isatins, malononitrile and anilinolactones using choline chloride (ChCl)/urea as a green solvent under microwave irradiation. It provided an efficient method for the synthesis of spirooxindole dihydropyridines in high to excellent yields. The catalytic system can be successfully reused eight times with a small decrease of its catalytic performance.

A novel magnetic metal–organic framework, NiFe2O4@MOF-5, has been prepared and characterized using spectroscopic, microscopic, and magnetic techniques (FT-IR, XRD, TEM, SEM, EDX, and VSM). This magnetically separable catalyst exhibited high catalytic activity for the synthesis of a variety of 2-substituted alkyl and aryl(indolyl)kojic acid derivatives via a one-pot, three-component reaction of aldehyde, indole, and kojic acid under solvent-free conditions. The catalyst can be easily magnetically separated and exhibits significant recyclability, with no significant loss of activity after six consecutive runs.

A magnetic metal–organic framework-based catalyst CoFe2O4@SiO2@IRMOF-3 was prepared and identified as an efficient catalyst for the synthesis of a variety of functionalized dihydro-2-oxopyrroles by a one-pot, four-component reaction of a dialkyl acetylenedicarboxylate, an aryl amine, formaldehyde, and optionally a second amine or diamine at room temperature. The catalyst was magnetically separated and recovered without significant loss of its catalytic efficiency, even after eight reaction cycles.

This study aimed to investigate effects of starch-protein interactions on physicochemical properties and in vitro starch digestibility of composite potato starch/protein blends (0, 5, 10, or 15% protein) during processing (cooking, cooling and reheating). The effect on recrystallization and short-range ordering in starch was studied by light microscopy, differential scanning calorimetry and Fourier transform infrared spectroscopy. The results show that protein in the blend proportionally restricted starch granule swelling during cooking and facilitated amylopectin recrystallization during cold-storage. The facilitating effect of protein diminished with increasing blend ratio. Resistant starch content in the processed blends was positively correlated to intensity ratio of 1053/1035 cm −1 in FTIR spectra arising from slow retrogradation of amylopectin ( r 2 > 0.88, P ≤ 0.05), whose formation was favored by the presence of protein in the blends and further enhanced by cooling of cooked blends. As a conclusion, starch-protein interaction reduced starch digestibility of the processed blends.

A simple, environmentally benign protocol for synthesis of hydrazones from carbonyl compounds and hydrazides has been developed in the presence of meglumine in aqueous-ethanol media at room temperature. The salient features of the present protocol are mild reaction conditions, short reaction time, high yields, operational simplicity, metal-free, applicability toward large-scale synthesis, and biodegradable and inexpensive catalyst.

A magnetic carbon nanotube supported Cu catalyst (CoFe2O4/CNT-Cu) was prepared, characterized and evaluated as a recoverable catalyst for synthesis of 3-nitro-2-arylimidazo[1,2-a]pyridines via one-pot three-component reactions of 2-aminopyridines, aldehydes and nitromethane. The reactions proceeded in PEG 400 under aerobic conditions and the products were obtained in good to excellent yields. The catalyst can be successfully recycled for eight runs without appreciable loss of its activity.

An efficient and simple synthetic approach has been developed for the preparation of biologically interesting spiro[oxindole-3,4’-(4′H-pyran)] derivatives via visible light-mediated one-pot, three-component reaction of isatins, 1,3-dicarbonyl compounds and malononitrile by using an inexpensive organic dye, Na2 eosin Y, as the photocatalyst in aqueous ethyl lactate at ambient temperature. The substrate scope of this three-component reaction is expanded to linear 1,3-dicarbonyl compounds as viable starting materials. All rights reserved.

Choline chloride and itaconic acid-based deep eutectic solvent has been identified as an effective catalyst and reaction medium for synthesis of 13-aryl-5H-dibenzo[b,i]xanthene-5,7,12,14(13H)-tetraones by condensation of 2-hydroxynaphthalene-1,4-dione with various aldehydes. The reaction conditions are mild and environmentally friendly.

An highly efficient and environmentally friendly process for the synthesis of α-aminophosphonates has been devised, through a one-pot three-component condensation of various aldehydes, amines and triethyl phosphate in water-ethyl lactate under ultrasonic irradiation conditions at room temperature. The expected products were obtained in high yield without the need for any additional catalyst.

A deep eutectic solvent (DES) based on choline chloride and malonic acid was prepared easily with high purity at a low cost. It has been applied as a dual catalyst and reaction medium for the synthesis of functionalized pyrroles by a one-pot, four-component reaction of amines, aldehydes, 1,3-dicarbonyl compounds and nitromethane. This green solvent could be recycled and reused three times without loss of its efficiency.

Deep eutectic solvents (DESs), also known as deep eutectic ionic liquids (DEILs) or low-melting mixtures (LMMs) or low transition temperature mixtures (LTTMs) in the literature, have become more and more attractive in recent years due to their interesting properties and benefits, such as low cost of components, easy to prepare, tunable physicochemical properties, negligible vapor pressure, non-toxicity, biorenewability and biodegradability. These eutectic mixtures have been widely used as green and sustainable media as well as catalysts in many chemical processes. This review focuses on recent advances using DESs in organic reactions including addition reactions, cyclization reactions, replacement reactions, multicomponent reactions, condensation reactions, oxidation reactions, and reducing reactions.

A simple, efficient, and eco-friendly procedure for the synthesis of a wide range of pyrazoles bearing a coumarin unit has been developed using a one-pot three-component reaction of salicylaldehyde, 4-hydroxy-6-methyl-2H-pyran-2-one, and hydrazine using meglumine as a catalyst in aqueous–ethanol media. This new protocol offers several advantages including the use of a biodegradable and inexpensive catalyst, short reaction time, high yields, and simple work-up procedure.

l -(+)-Tartaric acid–choline chloride based deep eutectic solvent has been found to be an effective promoted medium for Clauson-Kaas reaction of aromatic amines and 2,5-dimethoxytetrahydrofuran. Structurally diverse N -substituted pyrroles were obtained in high to excellent yields under mild conditions. The deep eutectic solvent is inexpensive, non-toxic, reusable and biodegradable.

This study evaluated the blending of flours made from an Ontario hard red winter wheat (HWF) and an Ontario soft red winter wheat (SWF) and compared it with a commercial standard noodle flour (control) made from Canadian Western Hard Red Spring wheat to assess the impact on white salted noodle-making performance and texture of cooked noodles. Flour characteristics, gluten aggregation, and starch pasting properties were assessed with a farinograph, GlutoPeak tester, and Rapid Visco Analyzer, respectively. The machinability of dough was evaluated with an SMS/Kieffer rig attached to a TA.XT Plus texture analyzer. Tensile and bite tests of cooked noodles were also conducted. Blending HWF with standard noodle flour decreased gluten strength and dough extensibility linearly proportional to the blend ratio, whereas a curvilinear response from blending SWF with standard noodle flour was observed. HWF demonstrated more favorable pasting properties except for lower peak viscosity for noodle making than sta...

Superparamagnetic CuFeO2 nanoparticles were prepared and characterized by XRD, SEM, TEM, FRIR spectroscopy, and vibrating sample magnetometry techniques. The catalytic activity of CuFeO2 nanoparticles was investigated in the one-pot, three-component reaction of 2-aminopyridines, aldehydes, and alkynes using citric acid–dimethylurea melt as a green solvent. An array of imidazo[1,2-a]pyridines were obtained in good to excellent yields. The catalytic system can be successfully reused six times with keeping its catalytic performance.

A magnetic CoFe 2 O 4 nanoparticle immobilized diamine- N -sulfamic acid (CoFe 2 O 4 @SiO 2 –DASA) was synthesized and used as efficient heterogeneous catalyst for the synthesis of amides via the Ritter reaction under solvent-free conditions. The magnetic nanocatalyst could be readily recovered by applying an external magnet and recycled several times without considerable loss of its catalytic activity.

Two novel [Ag 2 pyd] n ( 1 ) and [Ag 4 (apyz) 3 (pyd) 2 ·3H 2 O] n ( 2 ) supramolecular frameworks constructed by H 2 pyd (2,3-pyridinedicarboxylic acid) were synthesized and characterized by X-ray single crystal diffraction, elemental analyses and IR spectra. The pyd building block was extended into well-ordered supramolecular frameworks by Ag O and Ag···Ag interaction. Ligand-supported weak argentophilic interactions are observed in compounds 1 and 2 , but novel 1D Ag···Ag silver-wire structure is only in 1 . The linkers of pyd and apyz (aminopyrazine) play an important role in the self-assembly process. The combination of pyd ligands and Ag ions generate a 2D layer structure in complex 1 and pyd ligands adopt different coordination modes to connect Ag atoms to form 3D supramolecular framework in complex 2 . Comparing the experimental results, it is clear that the apyz ligand plays a crucial role in the formation of the resulting structures. The results are reported in this article.

Two new metal–organic framework namely, [ Ag 3 ( dmpyz ) 1.5 ( btc ) ] n (1), and [ Ag 2 ( dmpyz ) ( pta ) ] n (2), have been synthesized and structurally characterized. Compound 1 is a 3D structure incorporating μ 5 - ( η 1 , η 1 ) : ( η 1 , η 1 ) : ( η 1 , η 1 ) btc and μ 2 - N 1 , N 1 , μ 2 - N 2 , N 3 dmpyz ligands. In compound 2, the μ 5 - η 1 : η 2 : η 3 : η 1 pta and the dmpyz ligands link the [ Ag 4 O 2 ] units into a 2D structure. It is noteworthy that the Ag⋯Ag interactions were observed in the two coordination polymers. The results show that the structural diversity of the polymers is mainly attributed to the usage of diverse ancillary carboxylate ligands. The thermal stabilities and photoluminescence behaviors were addressed.

Two mixed-ligand silver(I) coordination complexes (CCs), [Ag 4 (mpyz)(npt) 2 ·(H 2 O) 2 ] n ( 1 ) and [Ag 4 (mpyz) (npt) 2 ] n ( 2 ) were synthesized with reactions of methyl-pyrazine(mpyz) and 3-nitro-1,2-benzenedicarboxylic acid (H 2 npt) with silver nitrate in different solvent systems and were structurally characterized by single-crystal X-ray crystallography. Structural differences of CCs are due to the effects of solvent systems and the intricacy of the self-assembly process for these systems. For 1 , the Ag 4 unit which is like Y letter which stand upside and down and repeat to form a 1D-6 3 -silver-ring which shares Ag1 and Ag2 only with npt ligands. The eight Ag ions of complex 2 are in a shape like the branches of a tree which repeat to form a 1D silver chain. Effects of solvents on the structures, as well as the intricacy of the self-assembly process were discussed. The photoluminescence, infrared spectroscopy (IR) and thermogravimetric analyses (TGA) behaviors of the compounds were also discussed.

A highly efficient magnetic CoFe2O4 chitosan sulfonic acid nanoparticle (CoFe2O4-CS-SO3H) was prepared and applied for one-pot, four-component synthesis of 2H-indazolo[2,1-b]phthalazine-triones by condensation of phthalic anhydride, hydrazinium hydroxide, 1,3-cyclohexanedione and aldehydes under solvent-free conditions at 80 °C. The magnetic nanocatalyst could be readily recovered by applying an external magnet and recycled several times without significant loss of its catalytic activity.

A novel magnetic nano-CoFe2O4 supported Sb ([CoFe2O4@SiO2–DABCO–Sb]) was successfully constructed, which exhibited high catalytic activity for one-pot three-component synthesis of multisubstituted pyrroles in the reaction of amines, nitroolefin and 1,3-dicarbonyl compounds. The magnetic heterogeneous catalyst could be easily recovered using an external magnet and reused many times without significant loss of catalytic activity.

A facile and highly efficient protocol for the one-pot, four-component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehydes and barbituric acid has been developed using meglumine as an inexpensive, biodegradable and reusable catalyst. This methodology provides a mild and fast route to structurally diverse tricyclic fused pyrazolopyranopyrimidines in good to excellent yields. Simplicity, room temperature reaction conditions, a green solvent, an easy work-up process, inexpensive price and reusability of the catalyst are the main advantages of this method.

Meglumine, a bio-based chemical, was demonstrated to be a highly efficient and reusable catalyst for the synthesis of a series of pyranopyrazole derivatives via a one-pot, four-component reaction of carbonyl compound or isatin, hydrazine hydrate, malononitrile, and β-keto ester in EtOH–H2O. The catalyst was found to work extremely for aldehydes, ketones or isatins at room temperature to give the corresponding dihydropyrano[2,3-c]pyrazole or spiro[indoline-3,4′-pyrano[2,3-c]pyrazole] derivatives in high yields. The salient features of this new methodology are broad substrate scope, room temperature reaction conditions, short reaction times, high yields, easy work-up process, reusability of catalyst, and the absence of hazardous organic solvents.

Interestingly, the substitution of epoxides (I) and (III) exerts a significant effect on the ring-opening direction.

The ultrasonic reactions of Ag2O with 1, 4-bis(imidazol-1-ylmethyl) benzene (bix) and ancillary carboxylate ligands under the ammoniacal condition lead to two new coordination compounds, namely [Ag4(bix)4(pma)·(H2O)18]n(1) and [Ag(bix)(onb)·H2O]n(2)(H4pma = pyromellitic acid, Honb = o-nitrobenzoic acid). Both of the complexes have been characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. In complex 1, the Ag-bix 1D chains are connected with the 2D nets containing [Ag4(bix)2(pma)2] to form a 3D framework by Ag⋯Ag interaction. In complex 2, the coordination bonds link Ag(I) ions and bix ligands to form 1D chains which are extended into a 2D layer by inter-chain hydrogen bonds. The Ag⋯Ag interaction is also observed in 2. Moreover, the photoluminescence properties of the complexes were also investigated in the solid state at room temperature.

Four Zn(II) coordination complexes, namely {[Zn(pmbm) 2 (tpa)]·H 2 O} n (1), {[Zn(pmbm)(phda)]·2(H 2 O)} n (2), [Zn(pmbm)(aze)] n (3), {[Zn(pmbm)(1,4-ndc)]·2(CH 3 OH)} n (4) [pmbm = 1-(4-pyridylmethyl)-benzimidazole, H 2 tpa = terephthalic acid, H 2 phda = phenylenediacetic acid, H 2 aze = azelaic acid, 1,4-ndcH 2 = 1,4-naphthalenedicarboxylic acid] have been synthesized by solution phase ultrasonic reactions of Zn(AC) 2 ·2H 2 O with pmbm and various dicarboxylates ligands under the ammoniacal condition. All the complexes have been characterized by elemental analyses, IR spectra and X-ray diffraction. Complexes 1 and 2 exhibit one-dimensional chains structure and complex 3 and 4 are two-dimensional sheets structure with (4,4) topology. Complexes 1 – 4 spanning from one-dimensional chains to two-dimensional sheets suggest that dicarboxylates play significant roles in the formation of such coordination architectures. The photoluminescences of the complexes were also investigated in the solid state at room temperature.

Four-component coupling of amines, aldehydes, 1,3-dicarbonyl compounds, and nitromethane has been achieved in gluconic acid aqueous solution (GAAS) to produce polysubstituted pyrroles in high yield. Gluconic acid aqueous solution could be recycled and reused several times without significant loss of its efficiency.

A low melting citric acid-urea mixture was found to be a new and effective promoting medium for the environmentally friendly synthesis of 1,8-dioxo-dodecahydroxanthene derivatives by condensation of aromatic aldehydes and cyclic 1,3-dicarbobonyl compounds. This deep eutectic solvent acts as both the reaction medium and catalyst, furnishing xanthenediones in high to excellent yields.

This study used 1H nuclear magnetic resonance (NMR) spin-spin relaxation time (T2) and differential scanning calorimetric (DSC) measurements of unfreezable water content (UFW), to assess water behavior in freshly prepared (25°C), refrigerator-stored (4°C, one day), or freezer-stored (–35°C, one day) doughs containing 5, 10, or 30% whole grain, air-classified β-glucan-diminished, and air-classified β-glucan-enriched (BGB-E) barley flours. Three populations of water were detected by NMR, depending on moisture content of dough, namely, tightly (T21, 2–5 msec), less tightly (T22, 20–50 msec), and weakly (T23, 100–200 msec) bound water. T22 peak was always detectable, and T22 peak time linearly correlated to moisture content of dough in a range of 0.7–2.0 g/g db (r = 0.99, P < 0.05). Freezer storage showed less effect on water mobility in dough compared with refrigerator storage, whereas cooking and cool storage of cooked dough significantly decreased the water mobility (P < 0.05). Adding barley flour...

A general, efficient, and green method for one-pot synthesis of functionalized spirooxindoles through three-component condensation reaction of isatins, cyclohexane-1,3-diones, and barbituric acids is described employing gluconic acid aqueous solution (GAAS) as a novel reaction medium and catalyst. The reaction medium could be recycled and reused several times without significant loss of its efficiency.

Ionic liquid supported synthesis of guanidine linked piperazine, diazepane, and aminomethylpiperidine to difluoroquinoxalinones and difluoro benzodiamine was achieved by two regioisomeric products. They were isolated from one pot reduction and intramolecular cyclization to afford quinoxalinone ring system with traceless cleavage of ionic liquid support. Besides, the ionic-supported other isomer was further cleaved in methanol. All the reactions were carried out on an ionic liquid support under various conditions to deliver biologically relevant scaffolds with high purity and excellent yields.

A simple, convenient, and multicomponent strategy for synthesis of spirooxindole derivatives has been developed. This strategy provides a rapid access to construct a diversity-oriented library of spirooxindoles by using three simple and readily available isatin, malononitrile or cyanoacetic ester, and 1,3-dicarbonyl compound catalyzed by hexamethylenetetramine in water.

Choline chloride and itaconic acid-based deep eutectic solvent has been identified as an effective catalyst and reaction medium for synthesis of 13-aryl-5H-dibenzo[b,i]xanthene-5,7,12,14(13H)-tetraones by condensation of 2-hydroxynaphthalene-1,4-dione with various aldehydes. The reaction conditions are mild and environmentally friendly.

An efficient approach for one-pot three-component reaction of aromatic amines, α,β-unsaturated aldehydes and β-keto esters using magnetic nanocrystalline Fe3O4 as a catalyst has been described. The corresponding 1,4-dihydropyridines are obtained in good yields under mild conditions. In addition, the catalyst can be recovered with a magnet and reused at least five consecutive cycles without appreciable loss of its catalytic activity.

Dodecyl benzenesulfonic acid functionalized silica-coated magnetic nanoparticles (γ-Fe2O3@SiO2-DDBSA) were readily prepared and identified as an efficient catalyst for the synthesis of a library of spirooxindole-pyrimidine derivatives by three-component condensation reaction of barbituric acids, isatins and cyclohexane-1,3-diones. The aqueous reaction medium, easy recovery of the catalyst using an external magnet, and high yields make the protocol sustainable and economic.