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The dopamine D4 receptor (D4R), a G protein-coupled receptor, is predominantly expressed in brain regions that control cognition, attention, and decision making. Previous studies have indicated that D4R-targeted ligands could be promising therapeutic targets for the treatment of several neuropsychiatric conditions, including substance use disorders (SUDs). There are currently no FDA-approved medications that selectively target D4Rs. New ligands may facilitate better understanding of the role of D4R-mediated signaling in drug-taking and drug-seeking behaviors. The present study focuses on the synthesis and evaluation of a novel series of benzothiazole analogues designed to target D4R. We identified several compounds with high D4R binding affinity (Ki ≤ 6.87 nM) and >91-fold selectivity over other D2-like receptors (D2R, D3R) with diverse partial agonist and antagonist profiles. Based on receptor affinity and functional analyses, 5f was identified as a potent low-efficacy partial agonist of the D4R and selected for further investigation. 5f was metabolically stable in rat and human liver microsome assays and displayed excellent brain penetration in rats. Using a within-session multidosing procedure, 5f (5, 15 and 30 mg/kg, i.p.) dose-dependently decreased i.v. infusions of three-unit doses of cocaine under a fixed-ratio (FR) FR3 schedule of reinforcement. These results are consistent with previous results produced by D4R-selective antagonists in SUD models, however off-target antagonism of 5-HT2A or 5-HT2B receptors may also contribute to these effects. Results with compound 5f support further efforts to target D4R in the treatment of SUDs. Further development of the benzothiazole scaffold may engineer out any serotonergic activity.

Linkers are emerging as a key component in regulating the pharmacology of bitopic ligands directed toward G-protein coupled receptors (GPCRs). In this study, the role of regio- and stereochemistry in cyclic aliphatic linkers tethering well-characterized primary and secondary pharmacophores targeting dopamine D2 and D3 receptor subtypes (D2R and D3R, respectively) is described. We introduce several potent and selective D2R (rel-trans-16b; D2R Ki = 4.58 nM) and D3R (rel-cis-14a; D3R Ki = 5.72 nM) agonists while modulating subtype selectivity in a stereospecific fashion, transferring D2R selectivity toward D3R via inversion of the stereochemistry around these cyclic aliphatic linkers [e.g., (-)-(1S,2R)-43 and (+)-(1R,2S)-42]. Pharmacological observations were supported with extensive molecular docking studies. Thus, not only is it an innovative approach to modulate the pharmacology of dopaminergic ligands described, but a new class of optically active cyclic linkers are also introduced, which can be used to expand the bitopic drug design approach toward other GPCRs.

The crystal structure of the dopamine D3 receptor (D3R) in complex with eticlopride inspired the design of bitopic ligands that explored (1) N-alkylation of the eticlopride's pyrrolidine ring, (2) shifting of the position of the pyrrolidine nitrogen, (3) expansion of the pyrrolidine ring system, and (4) incorporation of O-alkylations at the 4-position. Structure activity relationships (SAR) revealed that moving the N- or expanding the pyrrolidine ring was detrimental to D2R/D3R binding affinities. Small pyrrolidine N-alkyl groups were poorly tolerated, but the addition of a linker and secondary pharmacophore (SP) improved affinities. Moreover, O-alkylated analogues showed higher binding affinities compared to analogously N-alkylated compounds, e.g., O-alkylated 33 (D3R, 0.436 nM and D2R, 1.77 nM) vs the N-alkylated 11 (D3R, 6.97 nM and D2R, 25.3 nM). All lead molecules were functional D2R/D3R antagonists. Molecular models confirmed that 4-position modifications would be well-tolerated for future D2R/D3R bioconjugate tools that require long linkers and or sterically bulky groups.

In the search for novel bitopic compounds targeting the dopamine D3 receptor (D3R), the N-(2,3-dichlorophenyl)piperazine nucleus (primary pharmacophore) has been linked to the 6,6- or 5,5-diphenyl-1,4-dioxane-2-carboxamide or the 1,4-benzodioxane-2-carboxamide scaffold (secondary pharmacophore) by an unsubstituted or 3-F-/3-OH-substituted butyl chain. This scaffold hybridization strategy led to the discovery of potent D3R-selective or multitarget ligands potentially useful for central nervous system disorders. In particular, the 6,6-diphenyl-1,4-dioxane derivative 3 showed a D3R-preferential profile, while an interesting multitarget behavior has been highlighted for the 5,5-diphenyl-1,4-dioxane and 1,4-benzodioxane derivatives 6 and 9, respectively, which displayed potent D2R antagonism, 5-HT1AR and D4R agonism, as well as potent D3R partial agonism. They also behaved as low-potency 5-HT2AR antagonists and 5-HT2CR partial agonists. Such a profile might be a promising starting point for the discovery of novel antipsychotic agents.

To better understand the role of dopamine D

A main rationale for the role of G protein-coupled receptor (GPCR) heteromers as targets for drug development is the putative ability of selective ligands for specific GPCRs to change their pharmacological properties upon GPCR heteromerization. The present study provides a proof of concept for this rationale by demonstrating that heteromerization of dopamine Dsub1/suband Dsub3/subreceptors (Dsub1/subR and Dsub3/subR) influences the pharmacological properties of three structurally similar selective dopamine Dsub3/subR ligands, the phenylpiperazine derivatives PG01042, PG01037 and VK4-116. By using Dsub1/subR-Dsub3/subR heteromer-disrupting peptides, it could be demonstrated that the three Dsub3/subR ligands display different Dsub1/subR-Dsub3/subR heteromer-dependent pharmacological properties: PG01042, acting as G protein-biased agonist, counteracted Dsub1/subR-mediated signaling in the Dsub1/subR-Dsub3/subR heteromer; PG01037, acting as a Dsub3/subR antagonist cross-antagonized Dsub1/subR-mediated signaling in the Dsub1/subR-Dsub3/subR heteromer; and VK4-116 specifically acted as a ß-arrestin-biased agonist in the Dsub1/subR-Dsub3/subR heteromer. Molecular dynamics simulations predicted potential molecular mechanisms mediating these qualitatively different pharmacological properties of the selective Dsub3/subR ligands that are dependent on Dsub1/subR-Dsub3/subR heteromerization. The results of in vitro experiments were paralleled by qualitatively different pharmacological properties of the Dsub3/subR ligands in vivo. The results supported the involvement of Dsub1/subR-Dsub3/subR heteromers in the locomotor activation by Dsub1/subR agonists in reserpinized mice and L-DOPA-induced dyskinesia in rats, highlighting the Dsub1/subR-Dsub3/subR heteromer as a main pharmacological target for L-DOPA-induced dyskinesia in Parkinson's disease. More generally, the present study implies that when suspecting its pathogenetic role, a GPCR heteromer, and not its individual GPCR units, should be considered as main target for drug development.

The dopamine D4 receptor (D4R), a G protein-coupled receptor, is predominantly expressed in the prefrontal cortex in which it plays an important role in cognition, attention, and decision making. Studies have indicated D4R-selective ligands as promising therapeutic targets for the treatment of neuropsychiatric conditions such as substance use disorders (SUD). D4R ligands have been shown to alter cognition and behavior in animal models of drug addiction. A better understanding of D4R-mediated signaling is essential to treating D4R-associated disorders, including SUD. Despite its clinical importance, there are currently no FDA approved medications that target the D4R, and for example, treat cocaine use disorder. The present study focuses on the design of D4R-selective ligands based on the parental phenylpiperazine scaffold and pharmacokinetic analysis in rat and human liver microsomes, followed by in vivo pharmacokinetic and behavioral analysis. We identified several compounds with high binding affinity and D4R selectivity (Ki ≤ 6.87 nM and >91-fold vs. other D2-like receptors (D2R, D3R)) with diverse partial agonist and antagonist profiles. Based on the affinity profiles, 5f (CAB-01-019) was selected for an in vitro metabolic stability assay in rat and human liver microsomes which displayed an acceptable stability profile. Based on these results, we moved 5f forward into in vivo pharmacokinetic analysis in rats where it displayed excellent brain penetration with AUCbrain/plasma > 3. The full antagonist 5f (5, 15 and 30 mg/kg, i.p.) was tested in cocaine self-administration studies in rats, using a within-session multidosing procedure. 5f dose-dependently decreased the number of i.v. infusions obtained for three-unit doses of cocaine under a fixed ratio (FR) FR3 schedule of reinforcement, suggesting that the selected D4R antagonist reduced the rewarding effects of cocaine. Together, these results support the development of D4R-selective antagonists for SUDs and support 5f as a new probe for studying D4R-specific behaviors.

The need for safer pain-management therapies with decreased abuse liability inspired a novel drug design that retains μ-opioid receptor (MOR)-mediated analgesia, while minimizing addictive liability. We recently demonstrated that targeting the dopamine D3 receptor (D3R) with highly selective antagonists/partial agonists can reduce opioid self-administration and reinstatement to drug seeking in rodent models without diminishing antinociceptive effects. The identification of the D3R as a target for the treatment of opioid use disorders prompted the idea of generating a class of ligands presenting bitopic or bivalent structures, allowing the dual-target binding of the MOR and D3R. Structure-activity relationship studies using computationally aided drug design and in vitro binding assays led to the identification of potent dual-target leads (23, 28, and 40), based on different structural templates and scaffolds, with moderate (sub-micromolar) to high (low nanomolar/sub-nanomolar) binding affinities. Bioluminescence resonance energy transfer-based functional studies revealed MOR agonist-D3R antagonist/partial agonist efficacies that suggest potential for maintaining analgesia with reduced opioid-abuse liability.

The abuse of illicit psychostimulants such as cocaine and methamphetamine continues to pose significant health and societal challenges. Despite considerable efforts to develop medications to treat psychostimulant use disorders, none have proven effective, leaving an underserved patient population and unanswered questions about what mechanism(s) of action should be targeted for developing pharmacotherapies. As both cocaine and methamphetamine rapidly increase dopamine (DA) levels in mesolimbic brain regions, leading to euphoria that in some can lead to addiction, targets in which this increased dopaminergic tone may be mitigated have been explored. Further, understanding and targeting mechanisms underlying relapse are fundamental to the success of discovering medications that reduce the reinforcing effects of the drug of abuse, decrease the negative reinforcement or withdrawal/negative affect that occurs during abstinence, or both. Atypical inhibitors of the DA transporter and partial agonists/antagonists at DA D3 receptors are described as two promising targets for future drug development.

Recent studies have proposed that heteromers of µ-opioid receptors (MORs) and galanin Gal

In this paper, the benzo-cracking approach was applied to the potent sigma1 (σ1) receptor antagonist 1 to afford the less conformationally constrained 1,3-dioxane derivatives 2 and 3. To evaluate the effect of the increase in the distance between the two hydrophobic structural elements that flank the basic function, the cis and trans diastereomers of 4 and 5 were also prepared and studied. Compounds 2 and 3 showed affinity values at the σ1 receptor significantly higher than that of the lead compound 1. In particular, 3 displayed unprecedented selectivity over the σ2 receptor, the phencyclidine site of the NMDA receptor, and opioid receptor subtypes, as well as over the dopamine transporter. Docking results supported the structure–activity relationship studies. Due to its interesting biological profile, derivative 3, selected for an in vivo study in a validated preclinical model of binge eating, was able to counteract the overeating of palatable food only in binging rats, without affecting palatable food intake in the control group and anxiety-like and depression-related behaviors in female rats. This result strengthened the involvement of the σ1 receptor in the compulsive-like eating behavior and supported the σ1 receptor as a promising target for the management of eating disorders.

Missense mutations that give rise to protein misfolding are rare, but collectively, defective protein folding diseases are consequential. Folding deficiencies are amenable to pharmacological correction (pharmacochaperoning), but the underlying mechanisms remain enigmatic. Ibogaine and its active metabolite noribogaine correct folding defects in the dopamine transporter (DAT), but they rescue only a very limited number of folding-deficient DAT mutant proteins, which give rise to infantile Parkinsonism and dystonia. Herein, a series of analogs was generated by reconfiguring the complex ibogaine ring system and exploring the structural requirements for binding to wild-type transporters, as well as for rescuing two equivalent synthetic folding-deficient mutants, SERT-PG601,602AA and DAT-PG584,585AA. The most active tropane-based analog (9b) was also an effective pharmacochaperone in vivo in Drosophila harboring the DAT-PG584,585AA mutation and rescued 6 out of 13 disease-associated human DAT mutant proteins in vitro. Hence, a novel lead pharmacochaperone has been identified that demonstrates medication development potential for patients harboring DAT mutations.

A series of novel 1,4-dioxane analogues of the muscarinic acetylcholine receptor (mAChR) antagonist 2 was synthesized and studied for their affinity at M1–M5 mAChRs. The 6-cyclohexyl-6-phenyl derivative 3b, with a cis configuration between the CH2N+(CH3)3 chain in the 2-position and the cyclohexyl moiety in the 6-position, showed pKi values for mAChRs higher than those of 2 and a selectivity profile analogous to that of the clinically approved drug oxybutynin. The study of the enantiomers of 3b and the corresponding tertiary amine 33b revealed that the eutomers are (2S,6S)-(−)-3b and (2S,6S)-(−)-33b, respectively. Docking simulations on the M3 mAChR-resolved structure rationalized the experimental observations. The quaternary ammonium function, which should prevent the crossing of the blood–brain barrier, and the high M3/M2 selectivity, which might limit cardiovascular side effects, make 3b a valuable starting point for the design of novel antagonists potentially useful in peripheral diseases in which M3 receptors are involved.

In this study, starting from our selective D3R agonist FOB02-04A (5), we investigated the chemical space around the linker portion of the molecule via insertion of a hydroxyl substituent and ring-e...

The crystal structure of the dopamine D(3) receptor (D(3)R) in complex with eticlopride inspired the design of bitopic ligands that explored 1) N-alkylation of eticlopride’s pyrrolidine ring, 2) shifting the position of the pyrrolidine nitrogen, 3) expanding the pyrrolidine ring system, and 4) incorporating O-alkylations at the 4-position. Structure Activity Relationships (SAR) revealed that moving the N- or expanding the pyrrolidine ring was detrimental to D(2)R/D(3)R binding affinities. Small pyrrolidine N-alkyl groups were poorly tolerated, but addition of a linker and secondary pharmacophore (SP) improved affinities. Moreover, O-alkylated analogues showed higher binding affinities compared to analogously N-alkylated compounds, e.g., O-alkylated 33 (D(3)R, 0.436 nM and D(2)R, 1.77 nM) vs. the N-alkylated 11 (D(3)R, 6.97 nM and D(2)R, 25.3 nM). All lead molecules were functional D(2)R/D(3)R antagonists. Molecular models confirmed that 4-position modifications would be well-tolerated for future D(2)R/D(3)R bioconjugate tools that require long linkers and or sterically bulky groups.

In the search for novel bitopic compounds targeting the dopamine D3 receptor (D3R), the N-(2,3-dichlorophenyl)piperazine nucleus (primary pharmacophore) has been linked to the 6,6- or 5,5-diphenyl-1,4-dioxane-2-carboxamide or the 1,4-benzodioxane-2-carboxamide scaffold (secondary pharmacophore) by an unsubstituted or 3-F-/3-OH-substituted butyl chain. This scaffold hybridization strategy led to the discovery of potent D3R-selective or multitarget ligands potentially useful for central nervous system disorders. In particular, the 6,6-diphenyl-1,4-dioxane derivative 3 showed a D3R-preferential profile, while an interesting multitarget behavior has been highlighted for the 5,5-diphenyl-1,4-dioxane and 1,4-benzodioxane derivatives 6 and 9, respectively, which displayed potent D2R antagonism, 5-HT1AR and D4R agonism, as well as potent D3R partial agonism. They also behaved as low-potency 5-HT2AR antagonists and 5-HT2CR partial agonists. Such a profile might be a promising starting point for the discovery of novel antipsychotic agents.

Because of the large degree of homology among dopamine D2-like receptors, discovering ligands capable of discriminating between the D2, D3, and D4 receptor subtypes remains a significant challenge....

The discovery of functionally biased and physiologically beneficial ligands directed toward G-protein coupled receptors (GPCRs) has provided the impetus to design dopamine D2 receptor (D2R) targeted molecules that may be therapeutically advantageous for the treatment of certain neuropsychiatric or basal ganglia related disorders. Here we describe the synthesis of a novel series of D2R agonists linking the D2R unbiased agonist sumanirole with privileged secondary molecular fragments. The resulting ligands demonstrate improved D2R affinity and selectivity over sumanirole. Extensive in vitro functional studies and bias factor analysis led to the identification of a novel class of highly potent Go-protein biased full D2R agonists with more than 10-fold and 1000-fold bias selectivity toward activation of specific G-protein subtypes and β-arrestin, respectively. Intracellular electrophysiological recordings from midbrain dopamine neurons demonstrated that Go-protein selective agonists can elicit prolonged ligand-induced GIRK activity via D2Rs, which may be beneficial in the treatment of dyskinesias associated with dopamine system dysfunction.

The D3 dopamine receptor (D3R) has been suggested as a drug target for the treatment of a number of neuropsychiatric disorders, including substance use disorders (SUD). Many D3R-selective antagonists are bivalent in nature in that they engage two distinct sites on the receptor – a primary pharmacophore binds to the orthosteric site, where dopamine binds, whereas a secondary pharmacophore interacts with a unique secondary binding pocket (SBP). When engagement of the secondary pocket exerts allosteric activity, the compound is said to be bitopic. We recently reported the synthesis and characterization of two bitopic antagonists of the D3R, (±)-VK04–87 and (±)-VK05–95, which incorporated a racemic trans-cyclopropylmethyl linking chain. To gain a better understanding of the role of chirality in determining the pharmacology of such compounds, we resolved the enantiomers of (±)-VK04–87. We found that the (+)-isomer displays higher affinity for the D3R and exhibits greater selectivity versus the D2R than the (−)-isomer. Strikingly, using functional assays, we found that (+)-VK04–87 inhibits the D3R in a noncompetitive manner, while (−)-VK04–87 behaves as a purely competitive antagonist, indicating that the apparent allosteric activity of the racemate is due to the (+)-isomer. Molecular dynamic simulations of (+)-VK04–87 and (−)-VK04–87 binding to the D3R suggest that the (+)-isomer is able to interact with the SBP of the receptor whereas the (−)-isomer bends away from this pocket, thus potentially explaining their differing pharmacology. These results emphasize the importance of the linker, and its isomeric conformations, within extended-length molecules for their positioning and engagement within GPCR binding pockets.

The dopamine transporter (DAT) is critical for spatiotemporal control of dopaminergic neurotransmission and the target for therapeutic agents, including ADHD medications, and abused substances, such as cocaine. Here, we develop new fluorescently labeled ligands that bind DAT with high affinity and enable single-molecule detection of the transporter. The cocaine analogue MFZ2–12 (1) was conjugated to novel rhodamine-based Janelia Fluorophores (JF(549) and JF(646)). High affinity binding of the resulting ligands to DAT was demonstrated by potent inhibition of [(3)H]dopamine uptake in DAT transfected CAD cells and by competition radioligand binding experiments on rat striatal membranes. Visualization of binding was substantiated by confocal or TIRF microscopy revealing selective binding of the analogues to DAT transfected CAD cells. Single particle tracking experiments were performed with JF(549)-conjugated DG3–80 (3) and JF(646)-conjugated DG4–91 (4) on DAT transfected CAD cells enabling quantification and categorization of the dynamic behavior of DAT into four distinct motion classes (immobile, confined, Brownian, and directed). Finally, we show that the ligands can be used in direct stochastic optical reconstruction microscopy (dSTORM) experiments permitting further analyses of DAT distribution on the nanoscale. In summary, these novel fluorescent ligands are promising new tools for studying DAT localization and regulation with single-molecule resolution.

Resilience has become a popular term in spatial planning, often replacing sustainability as a reference frame. However, different concepts and understandings are embedded within it, which calls for keeping a critical stance about its widespread use. In this paper, we engage with the resilience turn in spatial planning and we dwell on the relation between resilience and sustainability from a planning perspective. Building on insights from ecology, complex system theory and epistemology, we question whether resilience can effectively act as a &lsquo, boundary object&rsquo, i.e., a concept plastic enough to foster cooperation between different research fields and yet robust enough to maintain a common identity. Whilst we do not predicate a dichotomy between resilience and sustainability, we argue that the shift in the dominant understanding of resilience from a descriptive concept, to a broader conceptual and normative framework, is bound to generate some remarkable tensions. These can be associated with three central aspects in resilience thinking: (i) the unknowability and unpredictability of the future, whence a different focus of sustainability and resilience on outcomes vs. processes, respectively, ensue, (ii) the ontological separation between the internal components of a system and an external shock, (iii) the limited consideration given by resilience to inter- and intra-generational equity. Empirical evidence on actual instances of planning for resilience from different contexts seems to confirm these trends. We advocate that resilience should be used as a descriptive concept in planning within a sustainability framework, which entails a normative and transformative component that resonates with the very raison d&rsquo, &ecirc, tre of planning.

The production context linked to the agricultural sector in Basilicata is not very competitive, especially in international contexts. In fact, there are few companies that occupy a good market position beyond the border. The reasons are to be found in the high degree of fragmentation, in the high percentage of small businesses, mainly family-run, and a general low propensity to entrepreneurship.

Missense mutations that give rise to protein misfolding are rare, but collectively, defective protein folding diseases are consequential. Folding deficiencies are amenable to pharmacological correction (pharmacochaperoning), but the underlying mechanisms remain enigmatic. Ibogaine and its active metabolite noribogaine correct folding defects in the dopamine transporter (DAT), but they rescue only a very limited number of folding-deficient DAT mutants, which give rise to infantile Parkinsonism and dystonia. Herein, a series of analogs was generated by reconfiguring the complex ibogaine ring system and exploring the structural requirements for binding to wild type transporters, and for rescuing two equivalent synthetic folding-deficient mutants, SERT-PG601,602AA and DAT-PG584,585AA. The most active tropane-based analog (9b) was also an effective pharmacochaperone in vivo, in Drosophila harboring DAT-PG584,585AA and rescued six out of 13 disease-associated human DAT mutants in vitro. Hence, a novel lead pharmacochaperone has been identified that demonstrates medication development potential for patients harboring DAT mutants.

Since its very inception in the late decades of the twentieth century, environmental assessment (EA) has been imbued with a complex interplay of power, knowledge and values. Despite instrumental rationality seemingly dominating current practices, actors are faced with growing relational complexity and seem to be slowly becoming increasingly mindful of political, social and cultural implications of EA. Within this context, this paper explores the role of statutory environmental consultees in strategic environmental assessment (SEA), by reflecting on issues of power among the different actors involved, the handling of values and the generation, use and exchange of knowledge in SEA processes. The authors adopted a framework for contemporary environmental governance to map actors’ strategies onto a conceptual space stretching along two directions: the polarization between confrontational and collaborative attitudes, and the tendency to underpin knowledge claims with factual evidence or subjective considerations. By dwelling on a case study concerning the SEA of a national programme to promote sustainable urban development in metropolitan areas in Italy, the use of objectivity to support either neutrality- or advocacy-oriented approaches is contrasted with the use of strategies where statutory consultees have shown more adaptive and confrontational behaviours – that hinge upon both political and scientific legitimacy – to pursue their particular organizational strategies agendas.

In the field of environmental protection, the reference to ecosystem services (ES) - the benefits that human beings derive, directly or indirectly, from ecosystem functions- is increasingly widespread. The objectives of the new energy strategy try to combine two public interests: Renewable Energy Sources (RES) and the landscape and its cultural, environmental and naturalistic values. However, RES has a spatial impact on the landscape and consequently on ES. This paper analyzes some critical aspects of their spatial mutual relationship considering an area of the Basilicata region including 5 municipalities (Cancellara, Pietragalla, San Chirico Nuovo, Tolve and Vaglio Basilicata) assessing changes in Habitat Quality coming from not-regulated wind farms installation. This represents an approach for the correct planning of renewable technologies, the management of the land use and its ecological, cultural and economic functions, in order to preserve biodiversity and sustainability.

This paper investigates how agri-food research and innovation (R&I) activity may interact with sustainable local development processes. The focus is on smart specialisation strategies and partnerships between agri-food business and research organisations, established under the open innovation paradigm. An exploratory study is carried out on recent (2010–19) agri-food R&I activity in Puglia (Italy), covering both projects and patents carried out by 47 research centres (affiliated to any of 11 research institutions) and 40 agri-food enterprises. Beside project data analysis based on categorisation, the methodology applied social network analysis to partnerships. Findings point to Sustainable Manufacturing and Human and Environmental Health being the prevalent target areas of innovation activity, thus resulting in some form of sustainable agricultural intensification, with a bias towards Industrial Biotechnology, Advanced Materials and Nanotechnology. Open innovation approaches seem to be still phasing in, and the innovation potential of agri-food enterprises appears to be largely untapped. Future research may address the friction between industry-driven smart specialisation strategies and place-based innovation patterns that harness the intangible potential of social and relational capital.

The term ‘polycentrism’ describes a model of territorial settlement of all human activities in which there are a plurality of connected centres. Polycentrism refers to two very important aspects: the morphological one, which concerns the distribution of built environment in the territory, and the functional one, which concerns the relations between the different poles.

From the beginning of the 21st century, following major global and European initiatives such as the Millennium Ecosystem Assessment (2005) and The Economics of Ecosystem and Biodiversity (2010), the idea that ecosystem services could be used as a decision support tool, gained considerable importance in several fields: from economy to public policy, from territorial planning to environmental assessment. Defined as the set of goods and services provided by ecosystems for the benefit of humans life quality, they express the potential to overcome traditional and not sufficiently effective approaches of policies and interventions undertaken so far for biodiversity conservation purposes. In urban and territorial planning disciplines, it is therefore necessary testing new tools capable of spatially explaining territorial components that constitute biodiversity hotspots or, specularly, threats to biological diversity persistence and resilience. Taking part to this methodological framework, this work assesses changes in habitat quality, considered as a proxy for biodiversity, in Tomar (Portugal), a study area particularly affected by forest fires-driven degradation phenomena. Results highlight the potential of such tools in explicating the role of different territorial threats on biodiversity conservation and points out the importance of proper natural and semi-natural environments’ management.

In Basilicata region (Italy), the “Lagonegro-Rotonda” cycling route had been realized in the framework of the policy instrument “The Pact” (Basilicata Region Development Pact - DGR 517 of 17 May 2016) managed by Basilicata Region Mobility and Infrastructures department. The realization of this cycling project involved eight Municipalities under leading role of Nemoli Municipality and FAL Ferrovie Appulo Lucane s.r.l., concessionaire of disused railway sections located in the southern part of the region.

[Image: see text] In this study, starting from our selective D(3)R agonist FOB02-04A (5), we investigated the chemical space around the linker portion of the molecule via insertion of a hydroxyl substituent and ring-expansion of the trans-cyclopropyl moiety into a trans-cyclohexyl scaffold. Moreover, to further elucidate the importance of the primary pharmacophore stereochemistry in the design of bitopic ligands, we investigated the chiral requirements of (+)-PD128907 ((+)-(4aR,10bR)-2)) by synthesizing and resolving bitopic analogues in all the cis and trans combinations of its 9-methoxy-3,4,4a,10b-tetrahydro-2H,5H-chromeno[4,3-b][1,4] oxazine scaffold. Despite the lack of success in obtaining new analogues with improved biological profiles, in comparison to our current leads, a “negative” result due to a poor or simply not improved biological profile is fundamental toward better understanding chemical space and optimal stereochemistry for target recognition. Herein, we identified essential structural information to understand the differences between orthosteric and bitopic ligand–receptor binding interactions, discriminate D(3)R active and inactive states, and assist multitarget receptor recognition. Exploring stereochemical complexity and developing extended D(3)R SAR from this new library complements previously described SAR and inspires future structural and computational biology investigation. Moreover, the expansion of chemical space characterization for D(3)R agonism may be utilized in machine learning and artificial intelligence (AI)-based drug design, in the future.

To obtain novel muscarinic acetylcholine receptor (mAChR) antagonists, the enantiomers of the hybrid compounds 3-5, in which the quinuclidin-3-yloxy fragment of solifenacin and the 6,6-diphenyl-1,4dioxane-2-yl moiety of 2 linked by an ester or ether spacer were embedded in the same chemical entity, were prepared and evaluated for their affinity at the five mAChR subtypes (M-1-M-5). Stereochemistry and the nature of the linker between the quinuclidine moiety and the 1,4-dioxane nucleus play an important role on the affinities of the compounds. The presence of an ether bridge confers higher affinities for all mAChR subtypes to the ligand. Interestingly, the ether enantiomer (R,S)-5 shows the highest affinity at all mAChR subtypes with K-p(i) values similar to that of solifenacin at M-3 and higher at the other subtypes. Unlike solifenacin, it shows a preference for M-1 mAChR subtype with respect to the other subtypes. This compound, lacking a permanent positive charge on the nitrogen atom, can be a useful tool for the pharmacological study of mAChRs in the central nervous system. (C) 2017 Elsevier Masson SAS. All rights reserved.

Antagonists that selectively target GluN2B-subunit-containing N-methyl-d-aspartate (NMDA) receptors are of major interest for the treatment of various neurological disorders. In this study, relationships between variously substituted benzo[7]annulen-7-amines and their GluN2B affinity were investigated. 2-Nitro-5,6,8,9-tetrahydrobenzo[7]annulen-7-one (8) represents the central building block for the introduction of various substituents at the 2-position and various 7-amino moieties. N-(3-Phenylpropyl)-6,7,8,9-tetrahydro-5H-benzo[7]annulen-7-amines with a 2-NO2 (7 c), 2-Cl (15 c), or 2-OBn group (22 c) show very high GluN2B affinity (Ki =1.6-3.6 nm). Docking studies revealed the same binding poses for benzo[7]annulen-7-amines and ifenprodil at the interface of GluN1b and GluN2B subunits. The large 2-OBn moiety of 22 c occupies a previously unrecognized subpocket, which explains its high GluN2B affinity (Ki =3.6 nm). In two-electrode voltage clamp experiments and cytoprotection assays, the high-affinity GluN2B ligands 7 c, 15 c, and 22 c could not inhibit the glutamate-/glycine-evoked current and cytotoxic effects. However, the analogous phenols 16 c ((3-phenylpropyl)amino moiety) and 16 d ((4-phenylbutyl)amino moiety) with 10-fold lower GluN2B affinity (Ki =28 and 21 nm, respectively) showed promising inhibition of glutamate-/glycine-evoked effects in both assays. The presence of a phenolic hydroxy group seems to be essential for inducing conformational changes of the receptor protein, which finally results in closure of the ion conduction pathway.

Both dopamine D3 receptor (D3R) partial agonists and antagonists have been implicated as potential medications for substance use disorders. In contrast to antagonists, partial agonists may cause fewer side effects since they maintain some dopaminergic tone and may be less disruptive to normal neuronal functions. Here, we report three sets of 4-phenylpiperazine stereoisomers that differ considerably in efficacy: the (R)-enantiomers are antagonists/weak partial agonists, whereas the (S)-enantiomers are much more efficacious. To investigate the structural basis of partial agonism, we performed comparative microsecond-scale molecular dynamics simulations starting from the inactive state of D3R in complex with these enantiomers. Analysis of the simulation results reveals common structural rearrangements near the ligand binding site induced by the bound (S)-enantiomers, but not by the (R)-enantiomers, that are features of partially activated receptor conformations. These receptor models bound with partial agoni...