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New neutral carbene complexes of gold(I) [Au(Im-Me)X] (X = Cl, Au1; X = Br, Au2; X = I, Au3) have been synthesized and fully characterized by different techniques, including NMR and UV-vis absorption spectroscopy and single crystal X-ray diffraction. The carbene ligand Im-Me is decorated with a glucoside fragment via a triazole linker, obtainable through a click chemistry reaction. The compounds retain the Au-NHC fragment in aqueous solvents, and an equilibrium between the neutral halo- and the cationic di-carbene form [Au(Im-Me)2]+ is observed, whose extent follows the trend Au1 < Au2 < Au3. Cytotoxicity studies on two cancer and two non-tumorigenic cell lines reflect the solution behavior, as a certain difference among the complexes was disclosed, with the iodo complex Au3 being more active and selective. The compounds interact with both DNA and protein model systems. The X-ray structure of the adduct formed upon the reaction of Au1 with bovine pancreatic ribonuclease (RNase A) reveals Au binding at the side chain of His105 of both protein molecules A and B of the asymmetric unit. The binding of gold atoms at both the nitrogen atoms of the imidazole ring of His15 and at the N-terminal tail has been found in the adduct formed with hen egg white lysozyme.

This study describes new platinum(II) cationic five-coordinate complexes (1-R,R’) of the formula [PtR(NHC)(dmphen)(ethene)]CF3SO3 (dmphen = 2,9-dimethyl-1,10-phenanthroline), containing in their axial positions an alkyl group R (methyl or octyl) and an imidazole-based NHC-carbene ligand with a substituent R’ of variable length (methyl or octyl) on one nitrogen atom. The Pt–carbene bond is stable both in DMSO and in aqueous solvents. In DMSO, a gradual substitution of dmphen and ethene is observed, with the formation of a square planar solvated species. Octanol/water partitioning studies have revealed the order of hydrophobicity of the complexes (1-Oct,Me > 1-Oct,Oct > 1-Me,Oct > 1-Me,Me). Their biological activity was investigated against two pairs of cancer and non-cancer cell lines. The tested drugs were internalized in cancer cells and able to activate the apoptotic pathway. The reactivity of 1-Me,Me with DNA and protein model systems was also studied using UV–vis absorption spectroscopy, fluorescence, and X-ray crystallography. The compound binds DNA and interacts in various ways with the model protein lysozyme. Remarkably, structural data revealed that the complex can bind lysozyme via non-covalent interactions, retaining its five-coordinate geometry.

Neurodegenerative diseases are often characterized by the formation of aggregates of amyloidogenic peptides and proteins that bring to the formation of neurofibrillary plaques. In this study, we investigate a series...

The oxidative addition of α-glucosyl and α-galactosyl halides to the platinum(0) complex [Pt(2,9-dimethyl-1,10-phenanthroline)(ethene)] has been investigated. In all cases the main reaction product is the five-coordinate Pt(II) complex containing in axial position an α-glycosyl fragment in the unusual 1C4 conformation. In the case of glucose, a minor product could be identified as the β isomer, which retains the typical 4C1 chair. The single crystal structures of two diastereomers are compared. The outcome of the reaction does not depend on the nature of the halide and is only slightly affected by the solvent. The addition mechanism is discussed, also in the light of literature data. Experimental data, along with DFT calculations, point towards a radical chain mechanism.

The growing concern about global warming and the consumption of fossil fuels has driven in recent decades the use of biomass as a renewable feedstock. In this context, vegetable oils, the corresponding fatty acids (FAs) and esters (FAEs) have primary importance: their esterification and transesterification lead to innovative products, that find application in several sectors, from biofuels to solvents, from surfactants to cosmetic ingredients and plasticizers. Lewis acid catalysis represents the most accredited methodology for developing processes of esterification and transesterification in line with sustainability requirements. The results available so far reveal the prevalent catalytic role of Zn(II) salts and coordination compounds, due to their beneficial eco-toxicological profile, combined with an appropriate acidity, finely tunable through selective functionalization. This review provides a picture of the state of the art in this important sector of biomass valorization.

The global trend towards the growth of urban population poses the issue of the public space influence on outdoor practices of different subjects. Urban public space is the carrier of an ever-increa...

This article describes the synthesis, characterization, and biological activity of novel square-planar cationic platinum(II) complexes containing glucoconjugated triazole ligands and a comparison with the results obtained from the corresponding five-coordinate complexes bearing the same triazole ligands. Stability in solution, reactivity with DNA and small molecules of the new compounds were evaluated by NMR, fluorescence, and UV–vis absorption spectroscopy, together with their cytotoxic action against pairs of immortalized and tumorigenic cell lines. The results show that the square-planar species exhibit greater stability than the corresponding five-coordinate ones. Furthermore, although the square-planar complexes are less cytotoxic than the latter ones, they exhibit a certain selectivity. These results simultaneously demonstrate that overall stability is a fundamental prerequisite for preserving the performance of the agents and that coordinative saturation constitutes a point in favor of their biological action.

In recent years, the applicative approach to smart governance in urban planning field has increasingly involved the decision-making processes of public administrations and has helped to solve economic, social and environmental challenges of cities. This approach has in fact allowed administrations to understand how changes are taking place in the territory and in real time, through big data, e-governance and city dashboards. However, the literature underlines the lack of decision-making models on which an agreement had been recognized for the organization and management of new projects on an urban scale. This need involves (1) understanding clearly the needs of all actors involved in a project (public or private financiers, public administration, control offices and stakeholders), (2) making optimal decisions w.r.t. the selected criteria, (3) providing a hedge against unexpected data changes. The main applicative goal is to have a full awareness of how much every single change means in economic, logistical and time lag terms. To this end, the authors investigate the viability of Decision Trees to support decision-making processes for urban planning.

The synthesis of a novel water-soluble Pt(0) complex [Pt(1-gluAc)(dmf)] containing a glucoconjugated 2-iminopyridine ligand and dimethylfumarate is reported. Highly diastereoselectivity leads to the prevalent formation of only one of the possible diasteroisomers, which has been characterized by mono- and bi-dimensional NMR techniques. The anticancer activity of the complex was evaluated against two couples of cell lines, and the IC50 values reveal that it is more cytotoxic than cisplatin but no selective toward cancer cells.

Processes of urbanization, market liberalization and exploitation of heritage can engender the fragmentation and deterioration of historical urban landscapes. Cultural paths are a central aspect of policies of cultural heritage valorisation. Hence, this study proposes the Cultural Paths Assessment Tool (PAST) as a methodological framework for individuating a network of paths connecting cultural heritage components and for assessing their usefulness. The relevance of the PAST lies in the combination of Space Syntax techniques, GIS analytic tools and qualitative analysis within a Multi-criteria analysis framework. The proposed methodology—applied to the analysis of the historical district of Marina in the city of Cagliari (Italy)—addresses the need to establish methodologies and analytic tools that support decision making processes for conserving, managing and valorising historic Urban landscapes.

The environmental issues and, in recent years, the Covid-19 pandemic determined an increasing consensus around the need for urban policies aimed at re-shaping the urban realm. The issue of equality and the related conditions of accessibility and usability emerge as critical requirements in the re-shaping of the urban landscape and mobility. As a consequence, the proposed article discusses a comprehensive literature review on the topics of usability and accessibility and of the complementary notions of disability and exclusion. The objectives of the literature review are to define a taxonomy of the different dimensions of usability and accessibility, to assess the relevance of the different forms of usability and accessibility across disciplinary fields related to urban and transportation studies, to identify the co-relations among specific aspects of urbanity and mobility and conditions of accessibility and usability. The proposed literature review is the preliminary stage of a study aimed at defining a methodological framework for quantitatively describing the urban environment in terms of its accessibility and usability. The proposed defines the theoretical framework of an analysis method for evaluating inequality incorporated into the urban environment and for facilitating smart decisions and holistic design in the context of urban planning.

Thematic paths are a central aspect of urban policies for cultural heritage valorization. In fact, thematic paths are central spatial features for structuring the image of a historical landscape. Hence, this study proposes the cultural paths assessment tool (PAST) as a methodological framework for individuating a network of routes connecting cultural heritage components and for assessing their usefulness. Usefulness is herein defined as the potential of a street network to support the meaningful experience of a historical urban landscape. PAST combines space syntax techniques, a geographic information system, and a qualitative analysis within a multi-criteria analysis framework for addressing four aspects of connecting cultural heritage components, including: (i) the individuation of relevant assets, (ii) the identification of the sub-network of most central street segments, (iii) the definition of the street network of thematic routes, (iv) the assessment of the usefulness of thematic paths, according to the criteria of usability, imageability, and accessibility. The proposed methodology, applied to the historical district of Marina in the city of Cagliari in Italy, supports planning and design processes in two ways: (1) by identifying street segments and squares comprising a network of thematic routes, (2) by individuating high-leverage interventions for improving the usefulness of thematic routes. Consequently, the proposed study addresses the need to establish methodologies and analytic tools that support decision making processes for conserving, managing, and valorizing historic urban landscapes.

The design of novel metal complexes with N-heterocyclic carbene (NHC) ligands that display biological activity is an active research field in organometallic chemistry. One of the possible approaches consists of the use of NHC ligands functionalized with a carbohydrate moiety. Two novel Au(I)&ndash, Au(I) dinuclear complexes were synthesized, they present a neutral structure with one bridging diNHC ligand, having one or both heterocyclic rings decorated with a carbohydrate functionality. With the symmetric diNHC ligand, the dicationic dinuclear complex bearing two bridging diNHC ligands was also synthesized. The study was completed by analyzing the antiproliferative properties of these complexes, which were compared to the activity displayed by similar mononuclear Au(I) complexes and by the analogous bimetallic Au(I)&ndash, Au(I) complex not functionalized with carbohydrates.

Octahedral Pt(IV) complexes (2Pt–R) containing a glycoconjugate carbene ligand were prepared and fully characterized. These complexes are structural analogues to the trigonal bipyramidal Pt(II) species (1Pt–R) recently described. Thus, an unprecedented direct comparison between the biological properties of Pt compounds with different oxidation states and almost indistinguishable structural features was performed. The stability profile of the novel Pt(IV) compounds in reference solvents was determined and compared to that of the analogous Pt(II) complexes. The uptake and antiproliferative activities of 2Pt–R and 1Pt–R were evaluated on the same panel of cell lines. DNA and protein binding properties were assessed using human serum albumin, the model protein hen egg white lysozyme, and double stranded DNA model systems by a variety of experimental techniques, including UV–vis absorption spectroscopy, fluorescence, circular dichroism, and electrospray ionization mass spectrometry. Although the compounds present similar structures, their in-solution stability, cellular uptake, and DNA binding properties are diverse. These differences may represent the basis of their different cytotoxicity and biological activity., An unprecedented direct comparison between the biological properties of Pt compounds with different oxidation states and almost indistinguishable structural features was performed. The reasons of the diverse activity and selectivity have been investigated through several techniques by evaluating structural and stability properties, cellular uptake, and the interaction with macromolecules.

Five-coordinate platinum(II) complexes represent a minority compared to the well-known class of square-planar species. However, since the first appearances in the literature, their general properties have attracted much interest. In particular, their potential to act as anticancer agents has been considered, and several studies have demonstrated their effectiveness as pro-drugs. The review traces the progress of these investigations over time and the subsequent refinements in the structures. It also reports their synthesis, general properties, cytotoxic activity and ability to interact with biological macromolecules.

The increases in urbanization, pollution, resource depletion, and climate change underline the need for urban planning policies that incorporate blue&ndash, green infrastructure (BGI) and ecosystem services. This paper proposes a framework for assessing BGI&rsquo, s effect on children&rsquo, s outdoor activities. This effect, called meaningful usefulness, is a central issue due to the influence of experiences with nature on children&rsquo, s development and the global trend of concentration of children in urban areas. Based on the concept of affordance, the methodology formalizes meaningful usefulness in terms of an index of usefulness of individual settings (IUIS) and a synthetic index of usefulness of BGI in a specific area (ISGI). These are determined via an audit protocol, Opportunities for Children in Urban Spaces (OCUS), which incorporates a set of indicators measuring micro-scale properties of individual places and contextual macro-scale factors. The methodology is applied to BGI components in Cagliari, Sardinia, Italy, which was selected for its superior density of urban green spaces. The application of the OCUS tool confirms its usefulness for investigating functional affordances incorporated into the trans-scalar structures of BGIs. The analytic protocol further contributes to the implementation of urban planning strategies within the smart city paradigm.

This paper shows a comprehensive literature review based on a comparative method that investigates a set of 25 papers from different disciplinary fields. The articles are retrieved from the Web of Science and SCOPUS databases and individuated through queries containing the key terms child, play, city, neighbourhood, outdoor space, public space, urban space, mobility. The timeframe considered spans from 2004 to present. The analysis focuses on three related aspects: (i) methodology; (ii) conceptual apparatus describing children’s experience of spaces; (iii) green spaces and natural elements incorporated in public space design considered as determinant of children’s outdoor activities. This paper provides detailed information on the relationship between the availability of natural settings and elements and children’s outdoor practices and activities. Retrieving from previous studies the concept of practicability the authors reflect on significance of natural elements in reinforcing the potential of the built environment to promote children’s independent playful practices. This study is instrumental in structuring an analytic methodology for determining a synthetic index of the practicability of public spaces. The relevance of a methodology for assessing practicability relies on its potential to enable a better understanding of conditions conducive to children’s independent playful practices and to support governance by assisting the implementation of strategies of urban regeneration within the smart city paradigm.

The global process of urbanization, and the modification of social interaction determined by the pandemic crisis, poses the issue of the place of vulnerable users and, in particular, children, within the contemporary city. This research aimed to elaborate a theoretical and methodological framework, based on the concepts of affordance and capability, for analyzing the potential of public spaces to enable and support children&rsquo, s independent activities. This potential, or meaningful usefulness, is expressed by the Index of Meaningful Usefulness of public Urban Spaces (IUIS). The latter is calculated via the tool &lsquo, Opportunities for Children in Urban Spaces&rsquo, (OCUS). This methodology is applied to the analysis of significant public spaces within the historic center of the city of Iglesias in Sardinia, Italy. The results reveal adequate usefulness of the selected spaces, while underlining criticalities related to intrinsic spatial and physical attributes. The application to the case study confirms the validity of the theoretical and methodological framework embodied in the OCUS tool for supporting urban design and planning by orienting place-shaping processes towards the acknowledgement of children&rsquo, s needs.

Children&rsquo, s independent activities within public spaces emerge as a fundamental condition for their development considered in the context of their needs: socialization, movement, autonomy, and enrichment of their creative, imaginative, and cognitive potential. The promotion of their independence represents a relevant issue for implementing the smart city paradigm. This paradigm calls for a methodological framework where the urban fabric&rsquo, s performance is evaluated via comprehensive analytic protocols. The proposed study presents an audit tool for evaluating the quality of urban spaces in terms of their practicability by children: the Survey on Conditions of Practicable Environments (SCOPE). The practicability of this research is establishing the quality of urban spaces&rsquo, usability, and it is expressed in terms of compositional, configurational, functional, and social factors of the built environment organized within a framework articulated in seven key dimensions (connectivity, convenience, comfort, commitment, conviviality, conspicuousness, and coexistence). The introduction of the concept of practicability and of indicators incorporating the demand for a children-sensitive perspective in the project of public spaces determine the novelty of the SCOPE procedure. This methodology was applied to an area in Central Cagliari, Italy, to evaluate the usability of public spaces. The results reveal that the proposed methodology is relevant for implementing the smart city paradigm because it addresses children&rsquo, s autonomy and their rights to the city by selecting and defining indicators to clarify and assess conditions of the built environment conducive to children&rsquo, s autonomy and independent social activities.

The rediscovery of the functional and symbolic role of environmental networks, cycling and pedestrian paths, and open spaces, particularly in the urban realm, leads to an increasing sensitivity to the discontinuity of territories generated by the main mobility networks. Thus, an instance of domestication emerges, resulting in transformation strategies of large mobility infrastructures - or their portions - into multi-functional pedestrian spaces. However, pedestrianisation interventions have not been completely defined within a theoretical system that clearly establishes modes and conditions of implementation. This article aims to point out how the conditions of hierarchy constitute a supporting tool for controlling and verifying the project of pedestrianisation. The article focuses on a concrete case of modification of an urban road network: the transformation of a portion of an important distributor road in the urban area of Cagliari into a pedestrian space. This analysis uses the fundamental conditions of hierarchy as a tool to assess to what extent the modification of the road network articulation has resulted in conditions of lesser inter-connectivity, legibility and functionality.

The synthesis and characterization of N,N′-diethyl (L-Et,Et) and N-ethyl,N′-methyl (L-Et,Me) glyoxal-bridged cyclam ligands are described, together with the X-ray crystal structure of the complex [MnCl2(L-Et,Me)]. Bleaching of morine in the presence of hydrogen peroxide by the corresponding Mn catalysts [MnCl2(L-Et,Et)], [MnCl2(L-Et,Me)] and [MnCl2(L-Me,Me)] has been studied in aqueous solution at three different pH values (8.0, 8.75, and 9.0). The results clearly show that increasing pH has a different effect on the three catalysts, and that the dimethyl derivative is by far the most active.

The rate of ring closure (kC) of o-(ω-alkenyl)aryl radicals by means of an intramolecular attack of the intermediate phenyl-type radical at the tethered double bond was found to be 4.2 × 108 s−1 (for 1•) and 7.6×107 s−1 (for 8•), both being 6-exo-trig processes, and 9.6 × 109 s−1 for the 5-exo-trig process of 3•. The kC rate constant of these radicals was calibrated with respect to a known rate of H-atom abstraction (kH). The photostimulated SRN1 reactions of radical clock precursor 1 with anions PhS− and (EtO)2PO− in Me2SO at 25 °C provided the rates of addition of these nucleophiles (kY) to intermediate 1• (3.2 × 108 and 2.5 × 109M−1 s−1, respectively). In contrast, the analogous reaction of a ketone enolate ion with precursor 1 did not take the expected SRN1 course; instead an elimination reaction was favoured. Similarly, the reactions of radical clock precursors 3 or 8 with the enolate ion failed. However, investigation of the distribution of 9-anthracenyl (11•) or 1-naphthyl (12•) radicals between two competing reactions, namely combination with a nucleophile and H abstraction from the solvent (Me2SO), was successful and eventually enabled us to find the kY values for the addition of the enolate ion to these two aryl radical intermediates (4.4 × 108 and 2.9 × 109M−1 s−1, respectively).