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A catalyst-free synthesis of phosphorothioates via a P–S cross-coupling reaction of thiols with dialkyl phosphites has been studied. With presented method, various phosphorothioates were obtained by the reaction of thiols with H-dialkyl phosphites in the presence of DMSO as both solvent and oxidant under transition-metal-free conditions. Mechanistic studies showed that the reaction proceeds with formation of a known disulfide intermediate via the oxidation of thiols in the presence of DMSO. Nucleophilic substitution of dialkyl phosphite with the disulfide intermediate gave phosphorothioate. The presented method is a convenient process for the synthesis of phosphorothioates under catalyst-free conditions.

1-Aminophosphonates are valuable compounds with wide range of applications in biological and industry. Various reaction conditions and catalysts have been reported for the synthesis of 1-aminophosphonates via three-component (dialkyl phosphite + aldehyde + amine) or two-component reaction (dialkyl phosphite + imine). Here a solvent-free synthesis of 1-aminophosphonates under very mild reaction conditions is reported. The three-component condensation reactions of dialkyl phosphite, carbonyl compound, and an amine gave 1-aminophosphonates in good to excellent yields under solvent- and catalyst-free conditions at ambient temperature. Hydrophosphorylation of imines in the presence of dialkyl phosphite under the same conditions gave also 1-aminophosphonates in good to excellent yields. These results showed that the reaction needs no catalyst or solvent for activation. It seems a tautomeric form of dialkyl phosphite (as one of the components) catalyzed the reaction. The reaction yield decreased using any solvent. In addition, a novel method is reported for the synthesis of N-deprotected 1-aminophosphonates (analogues of 1-amino acids) from N-PMP 1-aminophosphonate in the presence of TCCA. To understand the activity of the dialkyl phosphite under solvent-free conditions, the DFT calculations have provided insight into the basis of this activity.

The electrochemical reaction of amines, nitriles, amides, nitroaromatics, and imines has been proven to be a valuable method for the synthesis of various nitrogen-containing organic compounds. Synthetic uses of electrochemical methods for organic transformations of amines, nitriles, imines, and amides to heterocylic compounds and coupling products are discussed. This review aims to demonstrate the ongoing application of electrosynthesis in the preparation of various classes of organic compounds. Furthermore, to address the recent collective articles, this review also describes and summarizes manuscripts on the electrochemical reactions of amines, nitriles, amides, and imines from 2015 until today.

A highly selective synthesis of diethyl (E)-2-(alkylidene)-2-phosphonoacetonitriles via the Knoevenagel condensation reaction of carbonyl compounds with diethyl cyanomethylphosphonate is reported.

A novel approach for the stereoselective synthesis of vinylphosphonates via an aromatic aza-Claisen rearrangement of 1-aminophosphonates.

Background & Objective: Anti-tumor activity of some thioureas derivatives is well documented in literature and received considerable attention. The present study aims to synthesize and characterize some novel thioureas and carbonylthioureas as anti-tumor agents for MCF-7 breast cancer cells in vitro and in vivo. Materials and Methods: Several 1-allyl-3-(substituted phenyl), N,N'-(phenylene) bis(3- allyldithithiourea) and 1-cyclopropanecarbonyl-3-(substituted phenyl)-thioureas derivatives were synthesized and confirmed by FT-IR spectroscopy, NMR and 13C-NMR. Anti-tumor activity of these compounds was determined by various in vitro and in vivo assays including; MTT, tumor volume measurement as well as,99mTc-MIBI tumor uptake in MCF-7 tumor bearing nude mice. Results: Among all of the synthesized compounds, some thioureas derivatives [3i] and [4b] at 100 nM concentration exhibited significant inhibitory effects on the proliferation of MCF-7 cell in vitro. However, this inhibition was not observed in HUVEC human endothelial normal cells. In vivo anti-tumor effects of the synthesized compounds on MCF-7 xenograft mouse models demonstrated a reduction in the tumor volume for various concentrations between 2 to 10 mg/kg after 21 days. These effects were comparable with Tamoxifen as standard anti-estrogen drug. According to the 99mTc-MIBI biodistribution result, treatment of MCF-7 bearing nude mice with both [3i] and [4b] compounds at the maximum concentration (10 mg/kg) can lead to a significant decrease of 99mTc- MIBI tumor uptake. Conclusions: Compounds [3i] and [4b] suppressed the growth of MCF-7 cells in the xenograft nude mice at the doses that were well-tolerated. Our study suggests that these new compounds with their significant anti-tumor effects, may serve as useful candidates for breast cancer therapy.

Among analgesic drugs, the opioid class of compounds still remains one of the most important medicines for severe and chronic pain treatment. Hence, developing novel and effective synthetic method of morphine and its related compounds is still an important task in modern synthetic organic chemistry. Achieving this goal demands a comprehensive knowledge of these valuable alkaloids. The present review study aims to summarize the history of five major opioid alkaloids and their pharmacologic effects, as well as various synthetic and biosynthetic methods.

This article reports the synthesis of new Dye A from the reaction of 4-methyl 2-nitroaniline, NaNO2/H+, and sodium 1-naphtholate. Dye A responded with an obvious colour change visible to naked eyes to pH, ultraviolet light, and fluoride ion and was studied by UV–vis spectroscopy. Next, the reaction of Dye A with crotonic anhydride leads to the formation of MDye A. Subsequently, synthesis of a new type of photochromic and pH-sensitive colorimetric hydrogel consisting of a new azobenzene (MDye A), acrylic acid, acrylamide, N,N'-methylenebisacrylic amide as a crosslinking agent, and sodium acrylate in the presence of 2,2′-azobis(isobutyronitrile) as initiator and sorbitan monostearate (Span 60) as the dispersant or under a LED lamp (400 nm, 20 W) in the presence of CdS nanorods and β-cyclodextrin was studied. The products were characterized using 1H NMR,13C NMR, TGA, DTG, SEM, TEM, and FTIR spectroscopy. The synthesized new hydrogel showed good pH responsiveness and photoresponsiveness, which was investigated by UV–vis spectroscopy. Also, the effects of parameters such as amounts of CdS nanorods, cross-linker, and water, duration of pre-oxygenation, light intensity on the swelling of gel, and polymerization rate in the synthesis of hydrogel were investigated.

In this report, a green synthesis of N-sulfonyl amidines via the direct reaction of tertiary or secondary amines with sulfonyl azides is described. Transition metal- and catalyst-free conditions were used for the synthesis of biologically important N-sulfonyl amidines. Further studies showed that the reaction proceeded via in situ aerobic oxidation of amines under reflux conditions.

In this study, for the first time, nitroalkanes, especially nitromethane, have been used as electron acceptors for the highly chemoselective oxidation of alcohols in the presence of a TiO2 photocatalyst under 400 nm LED irradiation. The reactions showed excellent selectivity for the production of aldehydes. Interestingly, aldehydes such as benzaldehyde and p-methoxybenzaldehyde are stable under the reaction conditions. In the case of the use of 2-nitropropane and 2-methyl-2-nitropropane, the product imine, which is the result of the reaction of the aldehyde with aliphatic amine, is also obtained.

A highly chemo- and stereoselective synthesis of diethyl (

In this study, the double addition of dialkylphosphite to nitriles in a ZnCl2/Et3N system is described. The reaction was conveniently and directly used for the synthesis of biologically important 1-aminobisphosphonates (ABPs) from nitriles. The one-pot synthesis of 1-aminobisphosphonates from aldehydes via the in situ generation of nitriles is also described.

A practical and efficient method has been developed for the preparation of optically active α-hydroxyphosphonates through resolution of the racemates. Treatment of racemic diethyl 1-hydroxy-1-phenylmethylphosphonate (1) with (+)-dibenzoyl-L-tartaric anhydride gave two diastereomeric esters 2 and 3 in the presence of bismuth triflate (15 mol %) in an 86:14 ratio. The two diastereomeric esters were separated by simple column chromatography, and the structure for the major diastereomer was determined by X-ray crystallographic analysis. Simple hydrolysis of the isolated major diastereomer in the usual manner afforded (R)-O,O-diethyl-1-[hydroxyl(phenyl)methyl] phosphonate 1. The advantages of the present method are that the operation is simple and easy to handle, along with rapid and good yield preparations of both enantiomers of the racemic α-phosphonates 1. Diastereoselective reactions of various racemic α-hydroxyphosphonates with d-Bz-L-TA in the presence of Bi(OTf)3 are also described.

Organophosphonates are a group of chemical agents which have high bioactivity. In the present study, we aimed to investigate the anticancer activity of the synthesized β-lactam derivatives of α-amino phosphonates on solid tumor and human leukemic cell lines. The results show that one of these compounds, Diethyl [(3-phenoxy-2-oxo-4-phenyl-azetidine-1-yl)-phenyl-methyl]-phosphonate, is a potent anticancer agent which especially shows anti-leukemic activity. Flow cytometry study showed that this chemical agent causes the G1 phase cell cycle arrest and consequently apoptosis in NB4 cell line as an acute promyelocytic leukemia model. In fact, this agent induces cell differentiation and apoptosis, at low and high concentrations, respectively. Its combination with All-Trans Retinoic Acid shows a higher percentage of cells in the terminal differentiation stage. This evidence suggested that diethyl phosphonate might be a proper candidate for chemo-differentiation therapy in acute promyelocytic leukemia and even in other types of acute myeloid leukemia.

Magnetic decorated multi-walled carbon nanotubes (m-MWCNTs) were functionalized using 4-aminopyridine to introduce pyridine groups on the carbon nanotubes (mf-MWCNTs). The pyridine functionalized magnetic decorated multi-walled carbon nanotubes were used as a support for gold nanoparticles. A thorough structural characterization has been carried out by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM) images, EDS, CHN and spectroscopy. The mf-MWCNTs supported gold nanoparticles were found to be an efficient catalyst for the oxidation of alcohols in water.

Different size and shapes of CdS and ZnS nanoparticles have been synthesized, characterized and studied for photodegradation of organic dyes. In this study, effect of alkyl chain of dithiocarbamates was investigated for the size and shaped controlled CdS and ZnS nanoparticles. A thorough structural characterization of nanoparticles has been carried out by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM) images, EDS, XRD, and UV/vis spectroscopy. Results showed that the alkyl chain in dithiocarbamate complexes of zinc and cadmium systems plays a significant role in the final morphology of the CdS and ZnS nanoparticles. A photocatalytic degradation of UV-irradiated Methylene Blue solutions in the presence of ZnS and CdS nanoparticles was studied in order to examine the nanoparticles influence on photodegradation rates.

Herein we report the synthesis and characterization of β-CD functionalized core-shell Fe3O4 magnetic nanoparticles which were used as an adsorbent for removal of Lead (II) and Copper (II) ions from aqueous solution. Various characterization techniques including FTIR, TGA analysis, SEM, TEM, X-Ray diffraction patterns (XRD) and nitrogen adsorption- desorption measurements were employed to investigate the properties of the synthesized material. The influence of pH, contact time, metal ion concentration, adsorbent dosage of Lead (II) and Copper (II) ion removal were also studied. The isotherm models for both ions showed a fit to the Langmuir model. Thermodynamic parameters such as enthalpy, entropy and Gibbs free energy were also evaluated and the negative values of ΔH for both Lead (II) and Copper (II) ions indicated the exothermic nature their sorption.

Herein we report the synthesis and characterization of β-CD functionalized core-shell Fe3O4 magnetic nanoparticles which were used as an adsorbent for removal of Lead (II) and Copper (II) ions from aqueous solution. Various characterization techniques including FTIR, TGA analysis, SEM, TEM, X-Ray diffraction patterns (XRD) and nitrogen adsorption- desorption measurements were employed to investigate the properties of the synthesized material. The influence of pH, contact time, metal ion concentration, adsorbent dosage of Lead (II) and Copper (II) ion removal were also studied. The isotherm models for both ions showed a fit to the Langmuir model. Thermodynamic parameters such as enthalpy, entropy and Gibbs free energy were also evaluated and the negative values of ΔH for both Lead (II) and Copper (II) ions indicated the exothermic nature their sorption.

The easy synthesis of graphene oxide (GO)‐supported manganese dioxide (MnO2) nanoparticles as a stable heterogeneous nanocatalyst (MnO2@GO) is described. This catalyst was investigated in the synthesis of 1,2,4‐oxadiazoles from amidoximes and aldehydes via a cyclization and oxidation process. The nanocomposite was prepared and characterized using various techniques. The catalytic application of the nanocomposite was examined in the reaction of a variety of aldehydes with aliphatic and aromatic amidoximes. The stable and robust catalyst was recycled for seven consecutive runs without a significant decrease in the catalytic activity. The authors are grateful to the Research Council of University of Zanjan, Institute for Advanced Studies in Basic Sciences (IASBS), the University of British Columbia, the University of Alicante (VIGROB-173) and the Spanish Ministerio de Economía, Industria y Competitividad (CTQ2015-66624-P) for support of this work.

In this report, a green synthesis of

Alcohol to aldehyde conversion is a critical reaction in the industry. Herein, a new electrochemical method is introduced that converts 1 mmol of alcohols to aldehydes and ketones in the presence of N-hydroxyphthalimide (NHPI, 20 mol%) as a mediator; this conversion is achieved after 8.5 h at room temperature using a piece of Ni foam (1.0 cm2) and without adding an extra-base or a need for high temperature. Using this method, 10 mmol (1.08 g) of benzyl alcohol was also successfully oxidized to benzaldehyde (91%) without any by-products. This method was also used to oxidize other alcohols with high yield and selectivity. In the absence of a mediator, the surface of the nickel foam provided oxidation products at the lower yield. After the reaction was complete, nickel foam (anode) was characterized by a combination of scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), and spectroelectrochemistry, which pointed to the formation of nickel oxide on the surface of the electrode. On the other hand, using other electrodes such as Pt, Cu, Fe, and graphite resulted in a low yield for the alcohol to aldehyde conversion.

Among the various methods used to induce protein amyloid aggregation in vitro (quiescent/agitated/shaken incubation) and different strategies of modulating the aggregation, the quiescent incubation of an amyloidogenic protein (AP) solution at a defined temperature, and using polyphenolic small molecules, are most common. Using a typical ThT fluorescence assay, we have shown that at the lowest percentage of DMSO used, the thermomixer-shaken incubation of AP solution results in a high-yielding aggregation. Under these conditions, some polyphenols such as curcumin and quercetin are unable to redirect the process except at higher concentrations, as shown by CD spectroscopy and TEM. Based upon NMR experiments and MD simulations, we suggest that polyphenolic self-association is the main cause. Because of the different properties of n-mer particles of these polyphenols formed through self-association, the redirection of AP aggregation occurred differently. To prove the involvement of self-association, rosmarinic acid with a much lower tendency to self-associate was examined. It was unable to redirect the process even at concentrations two and three times those of the other two.

A novel, simple and efficient synthetic protocol has been developed for the synthesis of a series of thiazolidine-4-one and 3H-thiazole derivatives via a one-pot four-component condensation-cyclization reaction of hydrazine with allyl isothiocyanate and an α-haloketone in the presence of various aldehydes. This new protocol produces novel thiazolidine-4-one and 3H-thiazole derivatives in excellent yields. The remarkable features of this methodology are high yields, easy work-up and a one-pot simple reaction method.

Synthesis of 2,3-disubstituted 1-alkylpyrrolo[2,3-b]quinoxalines was accomplished through the reaction of 3-chloroquinoxalin-2-amines with internal alkynes in the presence of Pd(OAc) $$_{2}$$ , NaOAc, and KOtBu in DMSO. This method afforded desired pyrrolo[2,3-b]quinoxalines in 65–92% reaction yields. The minimum inhibition concentration and minimum bactericidal concentration determinations against Micrococcus luteus and Pseudomonas aeruginosa revealed that some of the synthesized compounds showed the same values compared to tetracycline. These compounds could be used in the future research for the development of new antibiotics.

Hydrogels are three-dimensional polymer networks which can be synthesized by different techniques, such as free-radical addition reaction which is the most well-known technique in functional vinyl monomer polymerization. Photopolymerization, as an attractive technique, has been used in radical polymerization of monomers and has revitalized interest in the idea that it congregates a wide range of economic and ecological expectations. Due to the spatial–temporal control and a mild curing process of polymerization, photoinitiator semiconductor nano-particles offer great advantages, such as effective and quantitative reaction. Cadmium sulfide nanowire, titanium dioxide (TiO2) nanotube, and TiO2 nanowire were used as visible photocatalysts for photopolymerization of acrylamide hydrogel without using any additive under the sunlight and purple LED irradiations. The effects of different synthetic parameters, including initiator type and concentration and type of light sources, were investigated to achieve hydrogels with maximum swelling capacity. The results showed that the swelling of hydrogel reached 80 g water/g hydrogel when the TiO2 nanowire was used as the photoinitiator. The synthesized semiconductors and hydrogels were characterized by X-ray diffractometry, adsorption isotherm, infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy. According to the results, the new initiators led to semiconductor-based hydrogels, achieved with high swelling property through a high-speed high-efficient photopolymerization reaction in a safe manner.

The regioselective synthesis of 1-alkyl-2-aryl-3-acyl pyrrolo[2,3-b]quinoxalines through palladium-catalyzed Heck coupling reaction/heteroannulation was reported. The reaction of N-alkyl/benzyl-3-chloroquinoxaline-2-amines with chalcones catalyzed by Pd(OAc)2 in the presence of KOtBu, as the base, in DMSO afforded the desired products in good-to-high yields. The MIC and MBC determinations revealed that these compounds could be used in the future research works for the development of antibiotics.

A simple method is reported for the synthesis of alkylaminophenols in moderate to good yields via a three-component, catalyst-free decarboxylative coupling of proline with salicylaldehyde and boronic acids.

In this study, a novel magnetic nanocarrier for hydrophobic drugs ( β -CD–PDA–MNPs) was fabricated using surface coating of Fe 3 O 4 nanoparticles with polydopamine (PDA) followed by functionalization with 6-thio- β -cyclodextrin (6-thio- β -CD). The obtained magnetic nanoparticles were employed to investigate their interactions with diclofenac (DCF) as a model hydrophobic drug. The resulting β -CD–PDA–MNPs were characterized by various methods including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and vibrating sample magnetometry (VSM). The newly fabricated magnetic nanocarrier exhibited considerably higher drug loading capacity as compared for its analogue lacking CD ligands. Moreover, the release profile of DCF from β -CD–PDA–MNPs showed a burst release during the initial 8 h followed by the drug sustained release. Facile coating of magnetic nanoparticles with PDA was therefore a robust synthetic procedure for the conversion of the nanoparticles into a drug vehicle.

Sulfonated polystyrene microsphere were functionalized using ethylene diamine to introduce amine groups to the polymer chains. The amine functionalized polymers were used as a support for gold nanoparticles. A thorough structural characterization has been carried out by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM) images, EDS, CHN and atomic absorption spectroscopy. The polymer supported gold nanoparticles was found to be an efficient catalyst for the oxidation of alcohols in water.

A simple, efficient, and novel method is developed for the synthesis of phosphoroamidates via an Atherton–Todd coupling reaction of amines with dialkyl H-phosphite using trichloroisocyanuric acid as an efficient and safe reagent. Treatment of amines with dialkyl H-phosphite and trichloroisocyanuric acid under base-free conditions gives phosphoroamidates in moderate to good yields. The reaction proceeded effectively to afford the corresponding phosphoroamidates via a dehydrogenative coupling of H-phosphonates with amines. This method is easy, rapid, and good-yielding for the synthesis of phosphoroamidates.

Graft polymerization onto the cellulose is one way to produce semisynthetic copolymers and semiconductors were hardly used as initiators. Maleylated cellulose (MC) with different degree of carboxyl groups was synthesized and degree of carboxyl groups was determined using titration method. Then the graft copolymers of acrylamide (AM) on MC were synthesized by titanium dioxide semiconductor photoinitiator in aqueous suspension under sunlight. The effect of different parameters, such as the degree of carboxyl groups, degassing of atmosphere, reactor type, light source, MC/AM ratio, and initiator concentration, was evaluated in the synthesis of graft copolymers. MC with a high degree of carboxyl groups about 2.8 mmol g−1 was selected for graft photopolymerization. Maximum monomer conversion (55%) for Maleylated cellulose-g-polyacrylamide (MC-g-PAM) was achieved with 0.5 mg TiO2, MC/AM = 0.056, argon atmosphere, sunlight source, and double quartz tube reactor. The maximum amount of equilibrium swelling (41 g g−1) was achieved for MC-g-PAM with 34% monomer conversion. The resulting graft copolymers were characterized by FT-IR, SEM, and TGA. Synthesis of MC-g-PAM using TiO2 nanoparticles (NPs) as the initiator was done successfully that shows the TiO2 NPs are useable in graft polymerization of acrylamide monomers onto the MC under sunlight.

Mononuclear complexes [Pt(ppy)(S∧S)] (1a, S∧S = O,O′-di(cyclohexyl)dithiophosphate (ctp); 2a, S∧S = O,O′-di(butyl)dithiophosphate (btp)) and [Pt(bzq)(S∧S)] (1b, S∧S = ctp; 2b, S∧S = btp) have been prepared by the reaction of precursor complexes [Pt(C∧N)Cl(dmso)], C∧N = deprotonated form of 2-phenylpyrdine (ppy) and 7,8-benzoquinoline (bzq), and potassium salt of S∧S ligands. All complexes were characterized by NMR spectroscopy, and the structure of 2b was further identified by single crystal X-ray determination. Although the complexes are not luminescent in solution at ambient temperature, they become strong emissive materials (bright green) in solid state (at room temperature) with high quantum yields and long lifetimes in the microsecond domain. In frozen glass state or at low temperature (solid state), these complexes become better emissive in relation to room temperature. UV–vis spectra, supported by TD-DFT calculations, indicate that 1ILCT (intraligand charge transfer) predominates over the other tra...

We report here a novel and facile method for the synthesis of (±)-4(5)-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (medetomidine) in a good yield in five steps. The method involves Wittig olefination of the phenylimidazolylketones, followed by a hydrogenation. We demonstrate that the Wittig alkenylation reaction provides a convenient step for the synthesis of medetomidine without requiring methylation and dehydration steps, which are problematic processes in the previous methods. Novel route for the synthesis of medetomidine.

Metal oxides are promising compounds for water-splitting systems toward hydrogen production. One of the most important methods to prepare nanosized metal oxides is the decomposition of metal complexes. Herein, different Mn oxides from the decomposition of β-cyclodextrin-Mn complex in different calcined temperatures were studied by scanning electron microscopy, thermal gravimetric analysis, X-ray diffraction and a few electrochemical methods. Using scanning electron microscopy, we propose a mechanism to answer to the question that how is Mn oxide formed by the decomposition of β-cyclodextrin-Mn complex. In the next step, usual chemometric methods, principal component analysis (PCA) and multivariate curve resolution-alternating least squares (MCR-ALS), were used to not only determine the number of components and data visualization, but also examine the square wave voltammograms of obtained Mn oxides from the decomposition of β-cyclodextrin-Mn complex. Water-oxidizing activities of the compounds under the presence of photo-produced Ru(bpy) 3 3+ were also considered.