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In recent decades, the food industry has focused on the search for potential sources of anthocyanins that are able to provide color to replace synthetic dyes and at the same time provide health benefits through food products. Thus, in the present work, we propose the Dahlia pinnata flower as a potential source of anthocyanins. The dahlia is a native, annual flower from Mexico with a wide diversity of shapes and colors. The ancestral use of the flower in several dishes, its abundance, and the intense color of the flowers known as black make the D. pinnata flower a suitable candidate to be considered as a potential source of anthocyanins. Thus, the aim of this research is the determination of its nutritional composition, anthocyanin profile, and antioxidant activity. For this purpose, proximate composition of petals was determined by the AOAC standard methods. Anthocyanins were extracted from the dried petals of the flower with 0.1% HCl in methanol and 70% aqueous acetone solution and purified through Amberlite-XAD7-HP resin. Then, the purified extracts were analyzed for antioxidant activity by the DPPH method and the anthocyanin profile was characterized by HPLC and UPLC-MS/MS. Results showed that D. pinnata flowers have a proximate composition similar to other important edible flowers with a high level of moisture (87%-92%) and fiber (6%-7%). The antioxidant activity of both purified extracts was considerable (2.6-12 g/ml) compared to other sources of anthocyanins. The anthocyanin profile of the purified extracts contains four main anthocyanins: delphinidin-3-glucoside, delphinidin-3-rutinoside, pelargonidin-3-sambubioside-5-glucoside, and peonidin-3-sambubioside-5-glucoside, the last two being uncommon as major anthocyanin components in other plant sources. PRACTICAL APPLICATION: We present a potential and novel source of anthocyanins based on anthocyanin content and antioxidant activity of Dahlia pinnata petals. On the basis of UPLC-MS/MS studies, we identified four main anthocyanins, so this information provides the opportunity to study the source in many areas such as natural pigment stabilization, food additives, and antioxidants.

Copper-catalyzed Alkyne-Azide Cycloaddition (CuAAC) click chemistry robustness has been demonstrated over recent years to produce 1,2,3-triazoles with excellent yields at mild conditions with simple purification methods. However, the consequences of having copper paramagnetic traces in final products, which complicate spectroscopic assignments and can produce inaccurate conclusions, has been scarcely discussed. Herein we present a strategy that combines X-Ray Diffraction (XRD) with 13C- paramagnetic Nuclear Magnetic Resonance spectroscopy, in order to demonstrate the presence of paramagnetic metal traces at standard Huisgen synthesis and purification conditions. We also demonstrate that the derivatization of 1,4-disubstituted-1,2,3-triazoles to produce 1,3,4,-trisubstituted-1,2,3.triazolium salts, promotes an efficient removal of Cu(II/I) moieties. Evidence of paramagnetic metal moieties is given using XRD structural analysis of abnormalities in torsional angles between substituents and the 1,2,3-triazole center, in parallel to 13C- paramagnetic NMR chemical shift and line width analysis. As model systems to demonstrate the importance of characterizing paramagnetic traces, we present the synthesis of novel 1-((3s,5s,7s)-adamantan-1-yl)-4-cyclopropyl-1H-1,2,3-triazole and its derivatized 1-((3s,5s,7s)-adamantan-1-yl)-4-cyclopropyl-3-methyl-1H-[1,2,3]-triazol-3-ium triflate salt.

The mechanochemical synthesis of drug–drug solid forms containing metformin hydrochloride (MET·HCl) and thiazide diuretics hydrochlorothiazide (HTZ) or chlorothiazide (CTZ) is reported. Characterization of these new systems indicates formation of binary eutectic conglomerates, i.e., drug–drug eutectic solids (DDESs). Further analysis by construction of binary diagrams (DSC screening) exhibited the characteristic V-shaped form indicating formation of DDESs in both cases. These new DDESs were further characterized by different techniques, including thermal analysis (DSC), solid state NMR spectroscopy (SSNMR), powder X-ray diffraction (PXRD) and scanning electron microscopy–energy dispersive X-ray spectroscopy analysis (SEM–EDS). In addition, intrinsic dissolution rate experiments and solubility assays were performed. In the case of MET·HCl-HTZ (χMET·HCl = 0.66), we observed a slight enhancement in the dissolution properties compared with pure HTZ (1.21-fold). The same analysis for the solid forms of MET·HCl-CTZ (χMET·HCl = 0.33 and 0.5) showed an enhancement in the dissolved amount of CTZ accompanied by a slight improvement in solubility. From these dissolution profiles and saturation solubility studies and by comparing the thermodynamic parameters (ΔHfus and ΔSfus) of the pure drugs with these new solid forms, it can be observed that there was a limited modification in these properties, not modifying the free energy of the solution (ΔG) and thus not allowing an improvement in the dissolution and solubility properties of these solid forms.

Mechanochemistry is considered an alternative attractive greener approach to prepare diverse molecular compounds and has become an important synthetic tool in different fields (e.g., physics, chemistry, and material science) since is considered an ecofriendly procedure that can be carried out under solvent free conditions or in the presence of minimal quantities of solvent (catalytic amounts). Being able to substitute, in many cases, classical solution reactions often requiring significant amounts of solvents. These sustainable methods have had an enormous impact on a great variety of chemistry fields, including catalysis, organic synthesis, metal complexes formation, preparation of multicomponent pharmaceutical solid forms, etc. In this sense, we are interested in highlighting the advantages of mechanochemical methods on the obtaining of pharmaceutical cocrystals. Hence, in this review, we describe and discuss the relevance of mechanochemical procedures in the formation of multicomponent solid forms focusing on pharmaceutical cocrystals. Additionally, at the end of this paper, we collect a chronological survey of the most representative scientific papers reporting the mechanochemical synthesis of cocrystals.

Nanoparticles of magnetite passivated with gelatin and starch were synthesised using a co-precipitation technique. The nanoparticles were characterised using ultraviolet-visible (UV-vis), dynamic light scattering (DLS), Zeta potential, transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The UV-vis spectra showed characteristic surface plasmon resonance of magnetite nanoparticles. The DLS results showed the nanoparticles to have average hydrodynamic diameters of 138 ± 2 and 283 ± 21 nm for particles passivated with gelatin and starch, respectively. The stability in a colloidal solution was greater in nanoparticles passivated with gelatin than nanoparticles obtained with starch, as can be seen by their Zeta potential value (-31 ± 2 and -16 ± 0.5 mV, respectively). According to the TEM evaluation, the use of gelatin allowed to obtain nanoparticles with a spherical morphology and an average size of 10 ± 2 nm. However, when using starch the nanoparticles exhibited diverse morphologies with an average size of 25 ± 7 nm. The XRD results confirmed the crystalline structure of the samples, which showed crystallite sizes of 14.90 and 24.43 nm for nanoparticles passivated with gelatin and starch, respectively. FTIR analysis proved the establishment of interactions between functional groups of biopolymers and magnetite nanoparticles.

A new non-symmetric phosphinito-thiophosphinito POCSP-Ni(II) pincer compound was synthetized and characterized. The molecular structure of [NiCl{C6H3-2-(OPPh2)-6-(SPPh2)}] (1) was unequivocally determined by single crystal X-ray diffraction analysis, showing the Ni center to be located into a slightly distorted square planar geometry. This compound was used as efficient catalyst in C-S couplings of disulfides with iodobenzenes, exhibiting good activity and selectivity as well as tolerance to different functional groups.

La respuesta numerica de Chilocorus cacti Linnaeus, 1767 (Coleoptera: Coccinellidae), como depredador de la cochinilla silvestre (Dactylopius opuntiae (Cockerell)), se determino a traves de estudios en laboratorio. Al cuantificar la dinamica de la respuesta numerica, se encontro que al aumentar la cantidad de presas ofrecidas, el depredador incremento el numero de huevos ovipositados y de presas depredadas. Segun las regresiones lineales simples realizadas: por cada dos presas ofrecidas, se incremento el numero de huevos ovipositados en 1.238 y el numero de presas depredadas en 0.554; y el numero de huevos ovipositados se incremento en 0.636 por cada dos presas depredadas.

This review updates the explosive development of gold catalysis for organic transformation focusing on the current literature over last 3 years. Recent investigations have shown that gold catalysis provides catalytically active systems, whereas selectivity and reusability are advantages over noncatalyzed organic transformations. The collected literature is focusing for new organic reactions and synthetic methodologies. Gold can also be suggested for green processes dedicated to fine chemicals, pharmaceuticals, and the food industry due to its recognized biocompatibility. The current review is focused on new methods in the organic synthesis that could be of interest in the wide area of organic chemistry for developing new catalytic pathways.

This chapter describes the chemistry of pincer compounds including metallacycles larger than 5, i.e., 6 and 7 membered, the synthetic procedures for the attaining of the ligands, and metalation procedures to produce the corresponding complexes. The consequences of increasing the size of the metallacycles are also discussed both in terms of structure of the complexes and their effects in catalysis when the complexes were designed or employed for these purposes in different transformations.

The design, synthesis, characterization and in vitro anticancer activity of a series of Ir(I) NHC complexes derived from 5,6-dinitrobenzimidazole is reported. The evaluation was performed in five human cancer cell-lines, namely glioblastoma (U-251), prostatic adenocarcinoma (PC-3), colorectal adenocarcinoma (HCT-15), mammary adenocarcinoma (MCF-7) and lung adenocarcinoma (SKLU-7), including healthy cells of African green monkey kidney (COS-7) for comparative purposes. The complexes exhibited better activity in comparison with the corresponding NHC ligand precursors. In particular, complex (4a) exhibited a good performance against PC-3 and SKLU-1 with IC50 values of 10.6 ± 0.9 μM and 10.4 ± 1.5 μM, respectively.

A scandium-triflate-catalyzed arylative desulfonation of diarylmethyl phenyl sulfones with arenes and heteroarenes was established. A variety of both sulfone and arene substrates were reacted to afford symmetric and nonsymmetric triarylmethanes in good yields. Further transformations of the resulting triarylmethanes and application to the concise synthesis of a bactericidal agent analogue were also demonstrated.

In the cation of the title salt, C18H20N3+·I−, the mesityl and phenyl rings are inclined to the central triazolium ring by 61.39 (16) and 30.99 (16)°, respectively, and to one another by 37.75 (15)°. In the crystal, molecules are linkedviaC—H...I hydrogen bonds, forming slabs parallel to theabplane. Within the slabs there are weak π–π interactions present involving the mesityl and phenyl rings [inter-centroid distances are 3.8663 (18) and 3.8141 (18) Å].

The diphosphinite 1,3-bis[(di-isopropylphosphinite)methyl]benzene (2) has been synthesized and its complexation in palladium chemistry investigated. Complex 3 represents the first example of a two six-member PCP pincer bis(phosphinite) species. A catalytic study of 3 in the Heck reaction, revealed this specie to have an outstanding activity in the olefination of iodo-, bromo- and chloro-benzenes. When compared with other PCP pincer complexes, the results show that both by increasing the ring size from five to six-membered and using phosphinite instead of phosphine groups lead to a more active catalyst.

The reactions of [Sn(Ph)2(Ph2PC6H4-2-S)2] with trans -[M(Cl)(CO)(PPh3)2] M=Ir, Rh afford the complexes [Rh(Ph2PC6H4-2-S)2(SnClPh2)] (1) and [Ir(CO)(Ph2PC6H4-2-S)2(SnClPh2)] (2) as final products of two processes, a transmetallation reaction and an oxidative addition process. The crystal structures of both complexes have been determined, showing the rhodium compound to be into a slightly distorted square base pyramidal geometry, while that of the iridium derivative can be described as a distorted octahedron.

The complexes cis -[M(Ph 2 PC 6 H 4 -2-S) 2 ] M=Ni, Pd, Pt were stereoselectively synthesized by transmetallation reactions of [M(Cl) 2 (NCC 6 H 5 ) 2 ] M=Pd, Pt or NiCl 2 ·6H 2 O with [Sn(R) 2 (Ph 2 PC 6 H 4 -2-S) 2 ] R=Ph, n Bu or t Bu. The conformation of the Pd and Pt derivatives being unequivocally confirmed by single crystal X-ray diffraction studies showing both metal centers to be into a slightly distorted square planar environment, the main distortion being due to the steric hindrance caused by the aromatic rings in the phosphine moiety.

Catalytically active cationic complexes generated in situ from newly synthesized gold(I) complexes containing triazolylidene ligands in combination with AgBF4 are used as effective catalysts in the reaction of isocyanides and aldehydes to form oxazolines.

We report on the synthesis of a variety of C,E-bidentate triazolylidene ruthenium complexes that comprise different donor substituents E (E=C: phenyl anion; E=O: carboxylate, alkoxide; E=N: pyridine at heterocyclic carbon or nitrogen). Introduction of these donor functionalities is greatly facilitated by the synthetic versatility of triazoles, and their facile preparation routes. Five different complexes featuring a C,E-coordinated ruthenium center with chloride/cymene spectator ligands and three analogous solvento complexes with MeCN spectator ligands were prepared and evaluated as catalyst precursors for direct base- and oxidant-free alcohol dehydrogenation, and for transfer hydrogenation using basic iPrOH as a source of dihydrogen. In both catalytic reactions, the neutral/mono-cationic complexes with chloride/cymene spectator ligands performed better than the solvento ruthenium complexes. The donor functionality had a further profound impact on catalytic activity. For alcohol dehydrogenation, the C,C-bidentate phenyl-triazolylidene ligand induced highest conversions, while carboxylate or pyridine donor sites gave only moderate activity or none at all. In contrast, transfer hydrogenation is most efficient when a pyridyl donor group is linked to the triazolylidene via the heterocyclic carbon atom, providing turnover frequencies as high as 1400 h-1 for cyclohexanone transfer hydrogenation. The role of the donor group is discussed in mechanistic terms. European Research Council Science Foundation Ireland

A series of gold(I) complexes [AuCl(trz)] were synthesized that contain 1,2,3-triazolylidene (trz) ligands with variable wingtip groups. In the presence of AgBF4, these complexes undergo ligand redistribution to yield cationic complexes [Au(trz)2]BF4 in high yields as a result of efficient carbene transfer. Identical reactivity patterns were detected for carbene gold complexes comprised of Arduengo-type IMes ligands (IMes=N,N⠲-dimesityl-imidazol-2-ylidene). Reaction of cationic complexes [Au(trz)2]+ with [AuCl(trz⠲)] afforded the heteroleptic complex [Au(trz)(trz⠲)]+ and [AuCl(trz)] (trz, trz⠲=triazolylidene ligands with different wingtip groups). Carbene transfer occurs spontaneously, yet is markeldy rate-enhanced in the presence of Ag+. The facile carbene transfer was exploited as a catalyst activation process to form active gold species for the aldol condensation of isocyanides and aldehydes to form oxazolines. The catalytic activity is strongly dependent on the presence of Ag+ ions to initiate catalyst activation. High turnovers (105) and turnover frequencies (10 4 h-1) were accomplished. Structural analysis at early stages of the reaction support the critical role of triazolylidene dissociation to activate the precatalyst and dynamic light scattering revealed the presence of nanoparticles (±100 nm diameter) as potential catalytically active species. Furthermore, the triazolylidene scaffold had no impact on the diastereoselectivity of the oxazoline formation, and chiral triazolylidenes did not induce any asymmetry in the product. The facile dissociation of carbenes from [AuCl(carbene)] in the presence of Ag+ ions suggests a less stable Au-Ccarbene interaction than often assumed, with potential implications for gold-catalyzed reactions that employ a silver salt as (putative) halide scavenger. European Research Council Science Foundation Ireland JSPS Funding Program for Next Generation World-Leading Researchers

A series of PEPPSI-type palladium(II) complexes was synthesized that contain 3-chloropyridine as an easily removable ligand and a triazolylidene as a strongly donating mesoionic spectator ligand. Catalytic tests in Suzuki–Miyaura cross-coupling reactions revealed the activity of these complexes towards aryl bromides and aryl chlorides at moderate temperatures (50 °C). However, the impact of steric shielding was the inverse of that observed with related normal Nheterocyclic carbenes (imidazol-2-ylidenes) and sterically congested mesityl substituents induced lower activity than small alkyl groups. Mechanistic investigations, including mercury poisoning experiments, TEM analyses, and ESI mass spectrometry, provide evidence for ligand dissociation and the formation of nanoparticles as a catalyst resting state. These heterogeneous particles provide a reservoir for soluble palladium atoms or clusters as operationally homogeneous catalysts for the arylation of aryl halides. Clearly, the substitution of a normal N-heterocyclic carbene for a more basic triazolylidene ligand in the precatalyst has a profound impact on the mode of action of the catalytic system. European Research Council Science Foundation Ireland

Palladation of N3-alkylated 1,2,3-triazolium salts with Pd(OAc)2 afforded a μ2−I2 bridged bimetallic complex [Pd(trz)I2]2 and monometallic bis(carbene) complexes Pd(trz)2I2 as a mixture of trans and cis isomers (trz = 1,2,3-triazol-5-ylidene). Addition of excess halide or modification of the palladation procedure from direct functionalization to a transmetalation sequence involving a silver intermediate allowed for chemoselective formation of the bis(carbene) complex, while subsequent anion metathesis with NaI produced the monometallic bis(carbene) complexes exclusively. Modification of the wingtip group had little influence on the metalation to palladium or rhodium(I) via transmetalation. According to NMR analysis using δC and 1JRh−C, subtle but noticeable tunability of the metal electronic properties was identified. In addition, phenyl wingtip groups as N-substituents in the triazolylidene ligands were susceptible to cyclopalladation in the presence of NaOAc and are thus not chemically inert. University College Dublin Swiss National Science Foundation Marie-Curie IEF Alfred Werner Foundation