Chemical composition of the essential oils of the berries of Juniperus oxycedrus L. ssp. rufescens (L. K.) and Juniperus oxycedrus L. ssp. macrocarpa (S. & m.) Ball. and their antioxidant activities

This study is outlined to probe the chemical composition of essential oil and in vitro antioxidant activity of Juniperus oxycedrus ssp. macrocarpa (S. & m.) Ball. and Juniperus oxycedrus L. ssp. rufescens (L. K.) berries, collected from four sites, according to their maturity phase. The chemical composition of the hydrodistilled essential oil was analysed by GC-MS. Forty-eight compounds were identified, accounting for approximately 79.8-98.9% of the oil. The main constituents were α-pinene, germacrene D, myrcene, abietadiene and cis-calamenene, their mean percentage vary according to their phenological stage. The antioxidant activity of the samples was determined by the ABTS and DPPH radical scavenging activities. Hawaria essential oil extracted from mature berries showed the highest antioxidant capacity.     

Turning on red and near-infrared phosphorescence in octahedral complexes with metalated quinones

We report the synthesis of π-bonded ruthenium, rhodium, and iridium o-benzoquinones [Cp*M(o-C(6)H(4)O(2))](n) [M = Ru (2), n = 1-; Rh (3), n = 0; Ir (4), n = 0] following a novel synthetic procedure. Compounds 2-4 were fully characterized by spectroscopic methods and used as chelating organometallic linkers, "OM-linkers", toward luminophore bricks such as Ru(bpy)(2)(2+), Rh(ppy)(2)(+), and Ir(ppy)(2)(+) (bpy = 2,2'-bipyridine; ppy = 2-phenylpyridine) for the design of a novel family of octahedral bimetallic complexes of the general formula [(L-L)(2)M(OM-linkers)][X](m) (X = counteranion; m = 0, 1, 2) whose luminescent properties depend on the choice of the OM-linker and the luminophore brick. Thus, dinuclear assemblies such as [(bpy)(2)Ru(2)][OTf] (5-OTf), [(bpy)(2)Ru(2)][Δ-TRISPHAT] (5-ΔT) {TRISPHAT = tris[tetrachlorobenzene-1,2-bis(olato)]phosphate}, [(bpy)(2)Ru(3)][OTf](2) (6-OTf), [(bpy)(2)Ru(4)][OTf](2) (7-OTf), [(bpy)(2)Ru(4)][Δ-TRISPHAT](2) (7-ΔT), [(ppy)(2)Rh(2)] (8), [(ppy)(2)Rh(3)][OTf] (9-OTf), [(ppy)(2)Rh(4)][OTf] (10-OTf), [(ppy)(2)Rh(4)][Δ-TRISPHAT] (10-ΔT), [(ppy)(2)Ir(2)] (11), [(ppy)(2)Ir(3)][OTf] (12-OTf), [(ppy)(2)Ir(4)][OTf] (13-OTf), and [(ppy)(2)Ir(4)][Δ-TRISPHAT] (13-ΔT) were prepared and fully characterized. The X-ray molecular structures of three of them, i.e., 5-OTf, 8, and 11, were determined. The structures displayed a main feature: for instance, the two oxygen centers of the OM-linker [Cp*Ru(o-C(6)H(4)O(2))](-) (2) chelate the octahedral chromophore metal center, whether it be ruthenium, rhodium, or iridium. Further, the carbocycle of the OM-linker 2 adopts a η(4)-quinone form but with some catecholate contribution due to metal coordination. All of these binuclear assemblies showed a wide absorption window that tailed into the near-IR (NIR) region, in particular in the case of the binuclear ruthenium complex 5-OTf with the anionic OM-linker 2. The latter feature is no doubt related to the effect of the OM-linker, which lights up the luminescence in these homo- and heterobinuclear compounds, while no effect has been observed on the UV-visible and emission properties because of the counteranion, whether it be triflate (OTf) or Δ-TRISPHAT. At low temperature, all of these compounds become luminescent; remarkably, the o-quinonoid linkers [Cp*M(o-C(6)H(4)O(2))](n) (2-4) turn on red and NIR phosphorescence in the binuclear octahedral species 5-7. This trend was even more observable when the ruthenium OM-linker 2 was employed. These assemblies hold promise as NIR luminescent materials, in contrast to those made from organic 1,2-dioxolene ligands that conversely are not emissive.     

On Oxygen‐Containing Groups in Chemically Modified Graphenes

Reduced graphenes (belonging to the class of chemically modified graphenes, CMG) are one of the most investigated and utilized materials in current research. Oxygen functionalities on the CMG surfaces have dramatic influences on material properties. Interestingly, these functionalities are rarely comprehensively characterized. Herein, the four most commonly used CMGs, mainly electrochemically reduced graphene oxide (ER‐GO), thermally reduced graphene oxide (TR‐GO), and the corresponding starting materials, that is, graphene oxide and graphite oxide, were comprehensively characterized by a wide variety of methods, such as high‐resolution X‐ray photoelectron spectroscopy, electrochemical impedance spectroscopy, UV/Vis spectroscopy, transmission electron microscopy (TEM), and voltammetry, to establish connections between the structures of these materials that carry different oxygen functionalities and their electrochemical behaviors. This was followed by the quantification of the negatively charged oxygen‐containing groups (OCGs) by UV/Vis spectroscopy and of the electrochemically reducible OCGs by voltammetry. Lastly, a biofunctionalization with gold nanoparticle (AuNP)‐modified DNA sequences was performed by the formation of covalent bonds with the carboxylic groups (? COOH) on the CMG surfaces. There was an evident predominance of functionalizable ? COOH groups on the ER‐GO surface, as confirmed by a higher amount of Au detected both with differential‐pulse voltammetry and impedance spectroscopy, coupled with visualization by TEM. We exploited the DNA–Au bioconjugates as highly specific stains to localize and visualize the positions of carboxylic groups. Our findings are very important to clearly identify the presence, nature, and distribution of oxygen functionalities on different chemically modified graphenes.     

Optimal single‐embryo mass spectrometry fingerprinting

In pre‐implantation embryos, lipids play key roles in determining viability, cryopreservation and implantation properties, but often their analysis is analytically challenging because of the few picograms of analytes present in each of them. Matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) allows obtaining individual phospholipid profiles of these microscopic organisms. This technique is sensitive enough to enable analysis of individual intact embryos and monitoring the changes in membrane lipid composition in the early stages of development serving as screening method for studies of biology and biotechnologies of reproduction. This article introduces an improved, more comprehensive MALDI‐MS lipid fingerprinting approach that considerably increases the lipid information obtained from a single embryo. Using bovine embryos as a biological model, we have also tested optimal sample storage and handling conditions before the MALDI‐MS analysis. Improved information at the molecular level is provided by the use of a binary matrix that enables phosphatidylcholines, sphingomyelins, phosphatidylserines, phosphatidylinositols and phosphoethanolamines to be detected via MALDI(±)‐MS in both the positive and negative ion modes. An optimal MALDI‐MS protocol for lipidomic monitoring of a single intact embryo is therefore reported with potential applications in human and animal reproduction, cell development and stem cell research. Copyright © 2013 John Wiley & Sons, Ltd.     

Intrinsic and Extrinsic Heavy-Atom Effects on the Multifaceted Emissive Behavior of Cyclic Triimidazole

Considering that heavy halogen atoms can be used to tune the emissive properties of organic luminogens, the understanding of their role in photophysics is fundamental for materials engineering. Here, the extrinsic and intrinsic heavy-atom effects on the photophysics of organic crystals were separately evaluated by comparing cyclic triimidazole ( TT ) with its monoiodo derivative ( TTI ) and its co-crystal with diiodotetrafluorobenzene ( TTCo ). Crystals of TT showed room-temperature ultralong phosphorescence (RTUP) originated from H-aggregation. TTI and TTCo displayed two additional long-lived components, the origin of which is elucidated through single-crystal X-ray and DFT/TDDFT studies. The results highlight the different effects of the I atom on the three phosphorescent emissions. Intrinsic heavy-atom effects play a major role on molecular phosphorescence, which is displayed at room temperature only for TTI . The H-aggregate RTUP and the I⋅⋅⋅N XB-induced (XB=halogen bond) phosphorescence on the other side depend only on packing features.     

Validation of a method for the determination of multiclass pesticide residues in fruit juices by liquid chromatography/tandem mass spectrometry after extraction by matrix solid-phase dispersion

A multiresidue method was developed and validated for the determination of pesticide residues (omethoate, dimethoate, carbendazim, propoxur, thiabendazole, carbaryl, pirimicarb, azinphos-methyl, methidathion, and iprodione) in fruit juices. The samples were extracted by matrix solid-phase dispersion with diatomaceous earth and analyzed by liquid chromatography/tandem mass spectrometry. The method detection limits were <0.2 ppb for all pesticides; the relative standard deviations for analyses of samples fortified over the range of 2-50 ng/g were <9%, and the recoveries for each pesticide were all between 77 and 102%. The proposed method was used to analyze 21 commercial fruit juices; pesticide residues were found in 71% of the samples.     

New mu-oxo octanuclear complexes of 3d elements stabilized by dialkylcarbamato ligands. Synthesis and X-ray crystal and molecular structures

The octanuclear aggregates M(8)(mu(4)-O)(2)(O(2)CN(i)()Pr(2))(12) [M = Mn(II) 1, Co(II) 2, Ni(II) 3] have been prepared in good yields by controlled hydrolysis of the corresponding metal carbamate precursors [M(O(2)CN(i)()Pr(2))(2)](n)(). X-ray analysis has shown compounds 1-3 to be isostructural. The core of 2 contains two distorted [M(4)O] tetrahedra related by an inversion center. The hexanuclear carbamates M(6)(O(2)CNEt(2))(12) in toluene undergo a metal redistribution process with formation of the hexanuclear carbamates M'(x)M' '(6-x)(O(2)CNEt(2))(12), M' = Co, M' ' = Mn, as evidenced by mass-spectrometric data. In the presence of moisture, the mixed octanuclear carbamates Co(x)Mn(6-x)(MnO)(CoO)(O(2)CNEt(2))(12) were promptly formed and detected by DCI/MS measurements. Mass spectral data of Co(8)(mu(4)-O)(2)(O(2)CN(i)Pr(2))(12) are also reported.     

The hydrolysis mechanism of the anticancer ruthenium drugs NAMI-A and ICR investigated by DFT-PCM calculations

(ImH)[trans-RuCl(4)(DMSO-S)(Im)], (Im = imidazole, DMSO-S = S-bonded dimethylsulfoxide), NAMI-A, is the first anticancer ruthenium compound that successfully completed Phase I clinical trials. NAMI-A shows a remarkable activity against lung metastases of solid tumors, but is not effective in the reduction of primary cancer. The structurally similar (ImH)[trans-RuCl(4)(Im)(2)], ICR (or KP418), and its indazole analog (KP1019) are promising candidate drugs in the treatment of colorectal cancers, but have no antimetastatic activity. Despite the pharmacological relevance of these compounds, no rationale has been furnished to explain their markedly different activity. While the nature of the chemical species responsible for their antimetastatic/anticancer activity has not been determined, it has been suggested that the difference between reduction potentials of NAMI-A and ICR may be the key to the different biological responses they induce. In this work, Density Functional Theory calculations were performed to investigate the hydrolysis of NAMI-A and ICR in both Ru(III) and Ru(II) oxidation states, up to the third aquation. In line with experimental findings, our calculations provide a picture of the hydrolysis of NAMI-A and ICR mainly as a stepwise loss of chloride ligands. While dissociation of Im is unlikely under neutral conditions, that of DMSO becomes competitive with the loss of chloride ions as the hydrolysis proceeds. Redox properties of NAMI-A and ICR and of their most relevant hydrolytic intermediates were also studied in order to monitor the effects of biological reductants on the mechanism of action. Our findings may contribute to the identification of the active compounds that interact with biological targets, and to explain the different biological activity of NAMI-A and ICR.     

Cooking activities during the Middle Ages: organic residues in ceramic vessels from the Sant'Antimo Church (Piombino-Central Italy)

A combined gas chromatography-electron ionization (GC-EI), atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) and MS/MS approach has been used for characterizing organic residues of ceramic vessels of different forms and dimensions recovered from a vault of the apse of the 13th century church of Sant'Antimo in Piombino (Central Italy). The artifacts studied in this investigation are pots, jugs, colanders and pans probably used for cooking meals or as food containers. GC-MS has shown the presence of different fatty acids and other nonpolar markers, while APCI ionization proved to be particularly useful in the detection of diterpenoids and diacylglycerols. The data show that some organic markers may be of animal origin, while others are typical constituents or biodegradation products of vegetables. This allows one to propose the main use of these articles as vessels for cooking meat and maybe vegetable broths and soups. As there is no strict correlation between organic markers and shape, form and dimension of the ceramic vessel, it appears that the different objects probably served the same function. Chemical characterization of the organic residues of ceramic vessels, together with all the other archaeological data, contributes to a better understanding of their uses and the customs of people in the Middle Ages in Central Italy.