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The synthesis of 2,3-dihydropyrazino[1,2-a]indol-4(1H)-ones through the in situ generation of 2-methide-2H-indole intermediate I starting from 2-indolylmethyl acetates under basic conditions/nucleophilic Michael addition/cyclization cascade reaction.

A nanocatalyst with chiral amino alcohol catalytic function was efficiently employed in the Henry reaction, easily recovered by centrifugation and reused without loss of activity.

Shoot growth angle is a fundamental determinant of plant form. In their later development, lateral branches maintain gravitropic setpoint angles (GSAs) in which growth is set and maintained relative to gravity. The typically non-vertical GSAs are the product of an auxin-dependent antigravitropic offset that counteracts underlying gravitropic response in the branch (Roychoudhryet al., 2013). Here we describe an earlier phase of branch development in which the young lateral shoot grows rootward, independently of gravity, promoting a spreading growth habit. In normal development, this phase of growth is terminated with the onset of the GSA programme, with branches then growing upwards to assume their mature form. The biophysical basis of the early rootward phase of branch growth can be traced back to greater cell proliferation on the upper, adaxial side that upon expansion, drives asymmetric growth. Our data indicate that cytokinin is involved in this process and that the transcription factor TCP1 is an important regulator of lateral shoot adaxial identity and differential ad-abaxial cell proliferation.

Fluorescent atomically precise Ag38(11-azido-2-ol-undecane-thiolate)24 nanoclusters are easily prepared using sodium ascorbate as a "green"reducer and are extensively characterized by way of elemental analyses, ATR-FTIR, XRD, SAXS, UV-vis, fluorescence spectroscopies, and theoretical modeling. The fluorescence and the atomically determined stoichiometry and structure, the facile and environmentally green synthesis, together with the novel presence of terminal azido groups in the ligands which opens the way to "click"-binding a wide set of molecular species, make Ag38(11-azido-2-ol-undecane-thiolate)24 nanoclusters uniquely appealing systems for biosensing, recognition and functionalization in biomedicine applications and in catalysis. This journal is

Modification of surface silanols is a topic of interest in the preparation of organo-functionalized silica particles. Herein, two novel contributions, mainly focused on separation science, were presented: i) the horizontal polymerization on silica surface by using the vinyl-triacetoxy silane and ii) a preparation of cysteine-based stationary phase via photo-click thiol-ene coupling. In the first derivatization step, the vinyl-triacetoxy silane was employed instead of conventional trichloro vinyl one. The one-step synthetic procedure needed imidazole as an activating agent in addition to the silica hydration. Modified silica particles offer a high loading of vinyl fragments and an extensive passivation of silanols such as to not require a subsequent end-capping procedure. The structural morphology of media was deeper characterized by combining infrared spectroscopy, solid-state nuclear magnetic resonance, and elemental analysis. A first application, the photo-click cysteine-based material was prepared by photo-click reaction and the stationary phase was employed in the separation of some conventional targets by hydrophilic interaction chromatography.

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With the aim to easily recover and reuse the catalyst, an efficient amino alcohol catalyst previously tested in the asymmetric addition of diethylzinc to several aromatic aldehydes has been immobilized on proper functionalized superparamagnetic core-shell magnetite-silica nanoparticles and employed in the Henry reaction in the semi-homogeneous phase. The nanocatalyst exhibits a promising catalytic activity that remains unchanged in the three catalytic cycles performed. The results prove that highly efficient catalysts, by being immobilized on suitable magnetic nanosupports, can be easily recovered and reused, maintaining their catalytic behavior.

Fluorescent atomically precise Ag

A stereodivergent approach for producing piperidine iminosugars has been developed employing a common optically active precursor. The key steps of the synthetic pathway are the double diastereoselection in the asymmetric dihydroxylation of the suitable chiral vinyl epoxy ester and the regio- and stereospecific opening of the epoxide ring with azide. The synthesis of two piperidine iminosugars, 1-deoxy-D-altronojirimycin and 1-deoxy-D-nojirimycin, was achieved by two related routes.

Noble metal thiolate nanoclusters are a new class of nanomaterials with molecular-like properties such as high dispersibility and fluorescence in the visible and infrared spectral region, properties highly requested in biomedicine for imaging, sensing and drug delivery applications. We report on three new silver phenylethane thiolate nanoclusters, differing for slight modifications of the preparation, i.e., the reaction solvent and the thiolate quantity, producing changes in the nanocluster composition as well as in the fluorescence behavior. All samples, excited in the range 250–500 nm, emit around 400 and 700 nm differing in the emission maxima and behavior. The silver thiolate nanoclusters have been characterized by way of C, H, S elemental analyses and Thermal Gravimetric Analysis (TGA) to determine the nanocluster composition, Scanning Transmission Electron Microscopy (STEM) to investigate the nanocluster morphology and UV-Vis and fluorescence spectroscopy to study their optical properties.

The first stereocontrolled total synthesis of iminosugar 1,4-dideoxy-1,4-imino-D-iditol is described. The key step in our approach was the double diastereoselection in the asymmetric dihydroxylation (AD) of suitable optically active olefin, the chiral vinyl azido alcohol 9. Performing the AD using the most common Cinchona alkaloids as ligands enabled us to identify the ligand of choice for the stereodivergent synthesis of 1,4-dideoxy-1,4-imino-D-iditol and 1,4-dideoxy-1,4-imino-D-galactitol. These type of iminosugars, both natural and unnatural, are intensively studied for their promising chemotherapeutic properties against viral infections, diabetes, cancer, and tuberculosis.

Some constituents of the Mediterranean diet, such as extra-virgin olive oil (EVOO) contain substances such as hydroxytyrosol (HT) and its metabolite homovanillic alcohol (HA). HT has aroused much interest due to its antioxidant activity as a radical scavenger, whereas only a few studies have been made on the HA molecule. Both chemical synthesis and extraction techniques have been developed to obtain these molecules, with each method having its advantages and drawbacks. In this study, we report the use of tyrosol from olive mill wastewaters as a starting molecule to synthesize HT and HA, using a sustainable procedure characterized by high efficiency and low cost. The effects of HT and HA were evaluated on two cell lines, THP-1 human leukemic monocytes and L-6 myoblasts from rat skeletal muscle, after treating the cells with a radical generator. Both HT and HA efficiently inhibited ROS production. In particular, HT inhibited the proliferation of the THP-1 leukemic monocytes, while HA protected L-6 myoblasts from cytotoxicity.

A linear β-amino alcohol ligand, previously found to be a very efficient catalyst for enantioselective addition of dialkylzinc to aromatic aldehydes, has been anchored on differently functionalized superparamagnetic core-shell magnetite-silica nanoparticles (1a and 1b). Its catalytic activity in the addition of dialkylzinc to aldehydes has been evaluated, leading to promising results, especially in the case of 1b for which the recovery by simple magnetic decantation and reuse was successfully verified. This journal is

Herein we describe a versatile approach to the pyrrolizidine alkaloids skeleton by tailoring our original strategy already used for the pyrrolidine iminosugars synthesis. The key steps are the regio- and stereoselective azidolysis of the suitable chiral vinyl epoxide and then asymmetric dihydroxylation of the corresponding azido alcohol by using (DHQ)2AQN as the ligand. Further optimized elaborations addressed to the closure of the two rings allowed us to achieve the target iminosugar with complete stereocontrol. The wide range of pyrrolizidine iminosugars’ biological properties make them a key focus of new drug research and therefore the development of synthetic strategies for obtaining them is of decisive importance.

Ochratoxin A (OTA) is a mycotoxin with a serious impact on human health. In Mediterranean countries, the black Aspergilli group, in particular Aspergillus carbonarius, causes the highest OTA contamination. Here we describe the synthesis of three polyphenolic flavonoids: 5-hydroxy-6,7-dimethoxy-flavone (MOS), 5,6-dihydroxy-7-methoxy-flavone (NEG), and 5,6 dihydroxy-flavone (DHF), as well as their effect on the prevention of OTA biosynthesis and lipoxygenase (LOX) activity in A. carbonarius cultured in a conducive liquid medium. The best control effect on OTA biosynthesis was achieved using NEG and DHF. In fungal cultures treated with these compounds at 5, 25, and 50 &mu, g/mL, OTA biosynthesis significantly decreased throughout the 8-day experiment. NEG and DHF appear to have an inhibiting effect also on the activity of LOX, whereas MOS, which did not significantly inhibit OTA production, had no effect on LOX activity. The presence of free hydroxyls in catecholic position in the molecule appears to be a determining factor for significantly inhibiting OTA biosynthesis. However, the presence of a methoxy group in C-7 in NEG could slightly lower the molecule&rsquo, s reactivity increasing OTA inhibition by this molecule at 5 &mu, g/mL. Polyphenolic flavonoids present in edible plants may be easily synthesized and used to control OTA biosynthesis.

BACKGROUND The Non-Communicating Children Pain Check List-Revised (NCCPC-R) is a clinical assessment tool used to assess and measure pain in children aged 3 to 18 years, with mental and intellectual disabilities, incapable to speak. AIM Aim of our study was to test the validity and reliability of the Italian version of the NCCPC-R in children with cognitive impairment, in order to obtain a valid tool for pain assessment in these children. DESIGN Prospective observational study. SETTING Pediatric Outpatient of Physical and Rehabilitative Medicine Department, and Pediatrics, Child Neurology and Psychiatry Department, Sapienza University, Rome. POPULATION 55 non-communicating children, with severe intellectual disability, aged 3-18 years. METHODS The guidelines for "translation, adaptation, and validation of instruments or scales for cross-cultural healthcare research" were used to translate the scale, which was administered by the parents/caregivers twice for 2 consecutive days, in association with NRS (Numerical Rating Scale). The reliability of the scale was evaluated using the intra and inter-class correlation coefficient (ICCs); Cronbach alpha coefficient was used to test the internal validity of the scale; "Receiver Operating Characteristic" (ROC) curves were used to compare pain-free scores with pain scores, determining threshold scores; Pearson correlation between NCCPC-R and NRS values was measured. RESULTS The InterCC between the first and the second interviewer at T0 was 0,97, the IntraCC of the first interviewer at T0-T1 was 0,89, showing a high correlation; the Cronbach alpha coefficient at T0 was 0,97, showing a high scale's validity. Pearson correlation between NRS and NCCPC-R values at T0 was 0,54 showing a medium level of agreement (P