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Organic electrode materials (OEMs) hold significant development potential in the field of batteries and are regarded as excellent complementary materials to resource‐limited inorganic electrode materials, which have recently been the subject of extensive research. As research deepens, an increasing number of scholars recognize the influence of weak bond interactions on the properties of OEMs. Generally, weak bond interactions have more pronounced effects on organic materials compared to inorganic ones. Among various weak interactions, hydrogen bonds are particularly noteworthy, having been proven to play crucial roles in adjusting electrode charge distribution, stabilizing crystal structures, and inhibiting cyclic dissolution. The studies of hydrogen bonds in OEMs are therefore of paramount importance for guiding their future development. In this review, we primarily summarize the research progress in hydrogen bond science within OEMs and discuss future research directions and development prospects in this area. Hoping to provide valuable references for the advancement of OEMs. [ABSTRACT FROM AUTHOR]

Two undescribed pyrrolizidine alkaloids, 13-dehydrosenkirkine (1) and chloromethylretrorsine (2), along with three known analogues, onetine (3), retrorsine (4), and usaramine N-oxide (5), were isolated from Jacobaea vulgaris Gaertn. The structures of the undescribed compounds were elucidated by extensive spectrometric and spectroscopic techniques, including HRESIMS, NMR, calculated 13C-NMR DP4+ analysis and comparison with experimental and calculated ECD spectra. The undescribed compounds were evaluated for their antitumour activity against HT29, HeLa, and HepG2 cells. In addition, the intramolecular interactions and quadrupolar couplings were revealed by investigating the geometrical and electronic properties of three typical otonecine-type PAs in DFT theory. [ABSTRACT FROM AUTHOR]

Four alkyl chains and cyclohexane modified FeII complexes [Fe(Ln)(L')](ClO4)2⋅solv (n=1, 2, 3, 4) were synthesized and characterized. X‐ray diffraction study showed that these complexes were constituted by asymmetric mononuclear FeII entities, incorporating alkyl‐chain‐modified bppCOOH (2,6‐bis(1H‐pyrazol‐1‐yl)isonicotinic acid) ligands and 6,6"‐2,6‐dimethoxyphenyl‐substituted terpy ligand (L'). Magnetic susceptibility measurements revealed that complexes 1, 2, and 3 were in the high spin state across the measured temperature range, whereas complex 4 displayed an incomplete spin crossover phenomenon, with a transition temperature (T1/2) at 240 K. Investigations into variable‐temperature structure and magneto‐structural correlations revealed that the integration of alkyl‐chain‐modified bipyridyl units fostered the π⋅⋅⋅π intra‐ and intermolecular interactions, contributing to distinct crystal stacking and spatial configurations in complex 4 when compared to its counterparts. These findings underscore the pivotal influence of intramolecular interactions on the FeII spin states and highlight the significance of designing flexible ligands for modulating spin‐crossover characteristics. [ABSTRACT FROM AUTHOR]

Eukaryotic proteins often feature modular domain structures comprising globular domains that are connected by linker regions and intrinsically disordered regions that may contain important functional motifs. The intramolecular interactions of globular domains and nonglobular regions can play critical roles in different aspects of protein function. However, studying these interactions and their regulatory roles can be challenging due to the flexibility of nonglobular regions, the long insertions separating interacting modules, and the transient nature of some interactions. Obtaining the experimental structures of multiple domains and functional regions is more difficult than determining the structures of individual globular domains. High‐quality structural models generated by AlphaFold offer a unique opportunity to study intramolecular interactions in eukaryotic proteins. In this study, we systematically explored intramolecular interactions between human protein kinase domains (KDs) and potential regulatory regions, including globular domains, N‐ and C‐terminal tails, long insertions, and distal nonglobular regions. Our analysis identified intramolecular interactions between human KDs and 35 different types of globular domains, exhibiting a variety of interaction modes that could contribute to orthosteric or allosteric regulation of kinase activity. We also identified prevalent interactions between human KDs and their flanking regions (N‐ and C‐terminal tails). These interactions exhibit group‐specific characteristics and can vary within each specific kinase group. Although long‐range interactions between KDs and nonglobular regions are relatively rare, structural details of these interactions offer new insights into the regulation mechanisms of several kinases, such as HASPIN, MAPK7, MAPK15, and SIK1B. [ABSTRACT FROM AUTHOR]

Organic photodetectors (OPDs) based on non‐fullerene acceptors (NFAs) have received considerable attention because of their potential for use in various commercial applications as near‐infrared (NIR) light sensing platforms. However, recent OPDs suffer from low NIR photoresponse and large dark/noise currents with narrow bandgap organic photoactive materials. Herein, a π‐bridge molecular engineering strategy replacing alkoxythienyl with benzothiadiazole for ultra‐narrow bandgap (ultra‐NBG) NFAs is designed to achieve simultaneously high photoresponse at NIR region and low noise current density, thereby leading to excellent NIR (≈1050 nm) detectivity (D*). The newly synthesized ultra‐NBG NFAs, namely COB and CBT with optical bandgaps below 1.14 eV, present high responsivity (R) with 0.369 and 0.080 A W−1, respectively, at a wavelength of 1050 nm. Especially, with effectively suppressed noise current density, COB‐based OPD exhibits a high NIR (≈1050 nm) D* value of 2.18 × 1011 cm Hz1/2 W−1 at −0.5 V bias. The obtained R and D* values for these NFAs exceed or are comparable to those of a commercial Si photodetector at 1050 nm. This work provides important insight into the π‐bridge molecular engineering strategy for ultra‐NBG NFAs, which facilitate achieving highly sensitive NIR OPDs with high NIR photoresponse and low dark/noise current. [ABSTRACT FROM AUTHOR]

Driven by the digitization and informatization of contemporary society, electrical sensors are developing toward minimal structure, intelligent function, and high detection resolution. Single‐molecule electrical measurement techniques have been proven to be capable of label‐free molecular recognition and detection, which opens a new strategy for the design of efficient single‐molecule detection sensors. In this review, we outline the main advances and potentials of single‐molecule electronics for qualitative identification and recognition assays at the single‐molecule level. Strategies for single‐molecule electro‐sensing and its main applications are reviewed, mainly in the detection of ions, small molecules, oligomers, genetic materials, and proteins. This review summarizes the remaining challenges in the current development of single‐molecule electrical sensing and presents some potential perspectives for this field. [ABSTRACT FROM AUTHOR]

IntroductionThe influenza virus genome consists of single-stranded RNAs and forms viral ribonucleoprotein (RNP) complexes. After viral genome replication in the nucleus, the viral RNP interacts with viral protein M1. The M1-viral RNP complex is exported to the cytoplasm via the CRM1-dependent pathway using NS2/NEP as an export adaptor protein. NEP is a 14 kDa protein and diffusely localizes in the nucleus and cytoplasm. Upon binding to the NLS motif of M1, NEP inhibits the nuclear accumulation of M1 and promotes the nuclear export of M1-viral RNP complex. However, the detail mechanism by which NEP binds to M1 only in the nucleus remains unclear.MethodsTo visualize the interaction of NEP with M1 in the formation of vRNP export complexes, we performed in situ proximity ligation assays. The close proximity of N-terminal and C-terminal domains of NEP was tested by split Renilla luciferase complementation assays in which the N-terminal and C-terminal fragments of Renilla luciferase were fused to the N-terminus and C-terminus of NEP, respectively.Results and discussionWe found that the intramolecular interaction of NEP inhibits the interaction of NEP with M1. The intramolecular interaction of NEP was mediated through the interaction of the N-terminal NES motif with the M1-binding domain at the C-terminus. By adding leptomycin B, a potent inhibitor of CRM1, the interaction of NEP with M1 was impaired. These results suggest that CRM1 disrupts the intramolecular interaction of NEP by recognizing the NES motif at the N-terminus of NEP, thereby promoting the interaction of NEP with M1. We also found that NEP mutant deficient in the intramolecular interaction was co-localized with M1 at the plasma membrane and did not show nuclear localization with M1. Based on these results, we propose that the intramolecular interaction of NEP regulated by CRM1 ensures the unidirectional transport of M1.

An intramolecular interaction between the p53 transactivation and DNA binding domains inhibits DNA binding. To study this autoinhibition, we used a fragment of p53, referred to as ND WT, containing the N-terminal transactivation domains (TAD1 and TAD2), a proline rich region (PRR), and the DNA binding domain (DBD). We mutated acidic, nonpolar, and aromatic amino acids in TAD2 to disrupt the interaction with DBD and measured the effects on DNA binding affinity at different ionic strengths using fluorescence anisotropy. We observed a large increase in DNA binding affinity for the mutants consistent with reduced autoinhibition. The ΔΔG between DBD and ND WT for binding a consensus DNA sequence is −3.0 kcal/mol at physiological ionic strength. ΔΔG increased to −1.03 kcal/mol when acidic residues in TAD2 were changed to alanine (ND DE) and to −1.13 kcal/mol when all the nonpolar residues, including W53/F54, were changed to alanine (ND NP). These results indicate there is some cooperation between acidic, nonpolar, and aromatic residues from TAD2 to inhibit DNA binding. The dependence of DNA binding affinity on ionic strength was used to predict excess counterion release for binding both consensus and scrambled DNA sequences, which was smaller for ND WT and ND NP with consensus DNA and smaller for scrambled DNA overall. Using size exclusion chromatography, we show that the ND mutants have similar Stokes radii to ND WT suggesting the mutants disrupt autoinhibition without changing the global structure. [ABSTRACT FROM AUTHOR]

Incorporating a third component through ternary copolymerization strategy has proven to be a promising and effective approach for further improving the device performance of polymer donors. However, terpolymer donors typically exhibit negative effects on molecular stacking and weaken charge transport due to the irregular distribution of the polymer skeleton. Herein, two terpolymers PBBQ-5 (5% ff-Qx) and PBBQ-10 (10% ff-Qx) are developed by introducing the difluoro-2-(3-hexyldecyloxy) quinoxaline (ff-Qx) to the main chain of PM6. The introduction of ff-Qx unit not only enables the terpolymers to possess N···S noncovalent intramolecular interactions that contribute to enlarge molecular planarity and enhance intramolecular interaction but also can fine-tuning electrostatic potential (ESP) values of the related polymers, thereby regulate intermolecular interactions with acceptor by electrostatic force. After blending with L8-BO, the PBBQ-5:L8-BO-based blend film exhibits appreciated miscibility, desirable phase separation sizes, and more ordered molecular packing than the analogs. Consequently, an impressive power conversion efficiency (PCE) as high as 19.54% is realized in PBBQ-5-based devices, which set a new record for Qx-based polymer solar cells. The work emphasizes the drawbacks of terpolymers and provides a new pathway for developing high-performance polymer donors by optimizing intra/inter-molecular interaction., (© 2025 Wiley‐VCH GmbH.)

We study for the first time whether triphenylphosphonium (TPP) moiety can improve cellular delivery and redox properties of amphipathic cationic peptides based on YRFK/YrFK cell-penetrating and cytoprotective motif. TPP moiety was found to increase reducing activity of both stereoisomeric peptides in solution and on electrode surface in association with TPP-mediated intramolecular interactions. Among TPP-conjugated peptides, newly synthesized TPP3-YrFK featured both increased antioxidant efficacy and proteolytic resistance. TPP-conjugated peptides preferably mitigated endogenic ROS in mitochondria and cytoplasm of model glioblastoma cells with increased oxidative status. This anti-ROS effect was accompanied by mild reversible decrease of reduced glutathione level in the cells with relatively weak change in glutathione redox forms ratio. Such low interference with cell redox status is in accordance with non-cytotoxic nature of the compounds. Intracellular concentrations of label-free peptides were analyzed by LC–MS/MS, which showed substantial TPP-promoted penetration of YrFK motif across cell plasma membrane. However, according to ΔΨm analysis, TPP moiety did not profoundly enhance peptide interaction with mitochondrial inner membrane. Our study clarifies the role of TPP moiety in cellular delivery of amphipathic cationic oligopeptides. The results suggest TPP moiety as a multi-functional modifier for the oligopeptides which is capable of improving cellular pharmacokinetics and antioxidant activity as well as targeting increased ROS levels. The results encourage further investigation of TPP3-YrFK as a peptide antioxidant with multiple benefits.

Intramolecular Cl−S non‐covalent interaction is introduced to modify molecular backbone of a benzodithiophene terthiophene rhodamine (BTR) benchmark structure, helping planarize and rigidify the molecular framework for improving charge transport. Theoretical simulations and temperature‐variable NMR experiments clearly validate the existence of Cl−S non‐covalent interaction in two designed chlorinated donors and explain its important role in enhancing planarity and rigidity of the molecules for enhancing their crystallinity. The asymmetric isomerization of side‐chains further optimizes the molecular orientation and surface energy to strike a balance between its crystallinity and miscibility. This carefully manipulated molecular design helps result in increased carrier mobility and suppressed charge recombination to obtain simultaneously enhanced short‐circuit current (Jsc) and fill factor (FF) and a very high efficiency of 15.73 % in binary all‐small‐molecule organic solar cells. [ABSTRACT FROM AUTHOR]

A novel green-absorbing organic molecule featuring dual intramolecular chalcogen bonds is synthesized and characterized. This molecule incorporates two such bonds: one between a tellurium atom and the oxygen atom of a carbonyl moiety, and the other between the tellurium atom and the adjacent nitrogen atom within a pyridine moiety. The molecule, featuring dual intramolecular chalcogen bonds exhibits a narrow absorption spectrum and elevated absorption coefficients, closely aligned with a resonance parameter of approximately 0.5. This behavior is due to its cyanine-like characteristics and favorable electrical properties, which are a direct result of its rigid, planar molecular structure. Therefore, this organic molecule forming dual intramolecular chalcogen bonds achieves superior optoelectronic performance in green-selective photodetectors, boasting an external quantum efficiency of over 65% and a full-width at half maximum of less than 95 nm while maintaining the performance after 1000 h of heating aging at 85 °C. Such organic photodetectors are poised to enhance stacked organic photodetector-on-silicon hybrid image sensors, paving the way for the next-generation of high-resolution and high-sensitivity image sensors., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

An H2O2 molecule was isolated inside hydroxylated open‐cage fullerene derivatives by mixing an H2O2 solution with a precursor molecule followed by reduction of one of carbonyl groups on its orifice. Depending on the reduction site, two structural isomers for H2O2@open‐fullerenes were obtained. A high encapsulation ratio of 81 % was attained at low temperature. The structures of the peroxosolvate complexes thus obtained were studied by 1H NMR spectroscopy, X‐ray analysis, and DFT calculations, showing strong hydrogen bonding between the encapsulated H2O2 and the hydroxy group located at the center of the orifice. This OH group was found to act as a kinetic stopper, and the formation of the hydrogen bonding caused thermodynamic stabilization of the H2O2 molecule, both of which prevent its escape from the cage. One of the peroxosolvates was isolated by HPLC, affording H2O2@open‐fullerene with 100 % encapsulation ratio, likely due to the intramolecular hydrogen‐bonding interaction. [ABSTRACT FROM AUTHOR]

The work is a continuation of the research on the use of NMR spectroscopy in the quality control of natural peptide hormone-based active substances and their synthetic analogues. The aim of the paper was to develop identification test methods for triptorelin acetate and goserelin acetate substances using NMR spectroscopy that does not require reference standards ‒ with the aim of using the newly developed test methods in pharmacopoeial analysis. Materials and methods: the procedure was developed using two-dimensional NMR spectroscopy (1H-1H gCOSY, 1H-13C gHSQC, 1H-13C gHMBC). Results: thestudy made it possible to assign 1H and 13C NMR signals to a specific molecular fragment, and to determine the amino acid composition of each oligopeptide. Conclusions: the authors drew up a table showing structural assignment of NMR signals, which makes it possible to use the NMR method for identification testing of triptorelin acetate and goserelin acetate substances without the use of pharmacopoeial reference standards. The study helped to determine the optimal temperature conditions for recording 13C NMR spectra (27 °С and 50 °С for triptorelin acetate and goserelin acetate, respectively). It was demonstrated that 13C NMR spectroscopy could be used for identification testing in pharmacopoeial analysis.

Arabidopsis cyclophilin38 (CYP38) is a thylakoid lumen protein critial for PSII assembly and maintenance, and its C-terminal region serves as the target binding domain. We hypothesized that four conserved residues (R290, F294, Q372, and F374) in the C-terminal domain are critical for the structure and function of CYP38. In yeast two-hybrid and protein pull-down assays, CYP38s with single-sited mutations (R290A, F294A, Q372A, or F374A) did not interact with the CP47 E-loop as the wild-type CYP38. In contrast, CYP38 with the R290A/F294A/Q372A/F374A quadruple mutation could bind the CP47 E-loop. Gene transformation analysis showed that the quadruple mutation prevented CYP38 to efficiently complement the mutant phenotype of cyp38. The C-terminal domain half protein with the quadruple mutation, like the wild-type one, could interact with the N-terminal domain or the CP47 E-loop in vitro. The cyp38 plants expressing CYP38 with the quadruple mutation showed a similar BN-PAGE profile as cyp38, but distinct from the wild type. The CYP38 protein with the quadruple mutation associated with the thylakoid membrane less efficiently than the wild-type CYP38. We concluded that these four conserved residues are indispensable as changes of all these residues together resulted in a subtle conformational change of CYP38 and reduced its intramolecular N-C interaction and the ability to associate with the thylakoid membrane, thus impairing its function in chloroplast.

In this study we aim to determine the origin of the electron density describing a CH···HC interaction in planar and twisted conformers of biphenyl. In order to achieve this, the fragment, atomic, localized, delocalized, intra‐ and inter‐atomic (FALDI) decomposition scheme was utilized to decompose the density in the inter‐nuclear region between the ortho‐hydrogens in both conformers. Importantly, the structural integrity, hence also topological properties, were fully preserved as no 'artificial' partitioning of molecules was implemented. FALDI‐based qualitative and quantitative analysis revealed that the majority of electron density arises from two, non‐classical and non‐local effects: strong overlap of ortho CH σ‐bonds, and long‐range electron delocalization between the phenyl rings and ortho carbons and hydrogens. These effects resulted in a delocalized electron channel, that is, a density bridge or a bond path in a QTAIM terminology, linking the H‐atoms in the planar conformer. The same effects and phenomena are present in both conformers of biphenyl. We show that the CH···HC interaction is a molecular‐wide event due to large and long‐range electron delocalization, and caution against approaches that investigate CH···HC interactions without fully taking into account the remainder of the molecule. [ABSTRACT FROM AUTHOR]

Arabidopsis cyclophilin38 (CYP38) is a thylakoid lumen protein critial for PSII assembly and maintenance, and its C-terminal region serves as the target binding domain. We hypothesized that four conserved residues (R290, F294, Q372, and F374) in the C-terminal domain are critical for the structure and function of CYP38. In yeast two-hybrid and protein pull-down assays, CYP38s with single-sited mutations (R290A, F294A, Q372A, or F374A) did not interact with the CP47 E-loop as the wild-type CYP38. In contrast, CYP38 with the R290A/F294A/Q372A/F374A quadruple mutation could bind the CP47 E-loop. Gene transformation analysis showed that the quadruple mutation prevented CYP38 to efficiently complement the mutant phenotype of cyp38. The C-terminal domain half protein with the quadruple mutation, like the wild-type one, could interact with the N-terminal domain or the CP47 E-loop in vitro. The cyp38 plants expressing CYP38 with the quadruple mutation showed a similar BN-PAGE profile as cyp38 , but distinct from the wild type. The CYP38 protein with the quadruple mutation associated with the thylakoid membrane less efficiently than the wild-type CYP38. We concluded that these four conserved residues are indispensable as changes of all these residues together resulted in a subtle conformational change of CYP38 and reduced its intramolecular N-C interaction and the ability to associate with the thylakoid membrane, thus impairing its function in chloroplast. [ABSTRACT FROM AUTHOR]

Low-dimensional Ruddlesden-Popper phase (LDRP) perovskites are widely studied in the field of photovoltaics due to their tunable energy-band properties, enhanced photostability, and improved environmental stability compared to the 3D perovskites. However, the insulating spacers with weak intramolecular interaction used in LDRP materials limit the out-of-plane charge transport, leading to poor device performance of LDRP perovskite solar cells (PSCs). Here, a functional ligand, 3-guanidinopropanoic acid (GPA), which is capable of forming strong intramolecular hydrogen bonds through the carboxylic acid group, is employed as an organic spacer for LDRP PSCs. Owing to the strong interaction between GPA molecules, high-quality LDRP (GPA) 2 (MA) n-1 Pb n I 3n+1 film with promoted formation of n = 5 phase, improved crystallinity, preferential vertical growth orientations, reduced trap-state density, and prolonged carrier lifetime is achieved using GPAI as the dimensionality regulator compared to butylamine hydroiodide (BAI). As a result, GPA-based LDRP PSC exhibits a champion power conversion efficiency of 18.16% that is much superior to the BA-based LDRP PSC (15.43%). Importantly, the optimized GPA-based LDRP PSCs without encapsulation show enhanced illumination, thermal, storage, and humidity stability compared to BA-based ones. This work provides new insights into producing high n value LDRP films and their efficient and stable PSCs., (© 2024 Wiley‐VCH GmbH.)

Summary: Transient receptor potential (TRP) channels are regulated by diverse stimuli comprising thermal, chemical, and mechanical modalities. They are also commonly regulated by phosphatidylinositol-4,5-bisphosphate (PIP2), with underlying mechanisms largely unknown. We here revealed an intramolecular interaction of the TRPP3 N and C termini (N-C) that is functionally essential. The interaction was mediated by aromatic Trp81 in pre-S1 domain and cationic Lys568 in TRP-like domain. Structure-function analyses revealed similar N-C interaction in TRPP2 as well as TRPM8/-V1/-C4 via highly conserved tryptophan and lysine/arginine residues. PIP2 bound to cationic residues in TRPP3, including K568, thereby disrupting the N-C interaction and negatively regulating TRPP3. PIP2 had similar negative effects on TRPP2. Interestingly, we found that PIP2 facilitates the N-C interaction in TRPM8/-V1, resulting in channel potentiation. The intramolecular N-C interaction might represent a shared mechanism underlying the gating and PIP2 regulation of TRP channels.

The tumor-suppressor p53 is a critical regulator of the cellular response to DNA damage and is tightly regulated by posttranslational modifications. Thr55 in the AD2 interaction motif of the N-terminal transactivation domain functions as a phosphorylation-dependent regulatory switch that modulates p53 activity. Thr55 is constitutively phosphorylated, becomes dephosphorylated upon DNA damage, and is subsequently rephosphorylated to facilitate dissociation of p53 from promoters and inactivate p53-mediated transcription. Using NMR and fluorescence spectroscopy, we show that Thr55 phosphorylation inhibits DNA-binding by enhancing competitive interactions between the disordered AD2 motif and the structured DNA-binding domain (DBD). Nonphosphorylated p53 exhibits positive cooperativity in binding DNA as a tetramer. Upon phosphorylation of Thr55, cooperativity is abolished and p53 binds initially to cognate DNA sites as a dimer. As the concentration of phosphorylated p53 is further increased, a second dimer binds and causes p53 to dissociate from the DNA, resulting in a bell-shaped binding curve. This autoinhibition is driven by favorable interactions between the DNA-binding surface of the DBD and the multiple phosphorylated AD2 motifs within the tetramer. These interactions are augmented by additional phosphorylation of Ser46 and are fine-tuned by the proline-rich domain (PRD). Removal of the PRD strengthens the AD2-DBD interaction and leads to autoinhibition of DNA binding even in the absence of Thr55 phosphorylation. This study reveals the molecular mechanism by which the phosphorylation status of Thr55 modulates DNA binding and controls both activation and termination of p53-mediated transcriptional programs at different stages of the cellular DNA damage response. [ABSTRACT FROM AUTHOR]

Ultralong organic phosphorescence (UOP) has attracted increasing attention due to its potential applications in optoelectronics, bioelectronics, and security protection. However, achieving UOP with high quantum efficiency (QE) over 20 % is still full of challenges due to intersystem crossing (ISC) and fast non‐radiative transitions in organic molecules. Here, we present a novel strategy to enhance the QE of UOP materials by modulating intramolecular halogen bonding via structural isomerism. The QE of CzS2Br reaches up to 52.10 %, which is the highest afterglow efficiency reported so far. The crucial reason for the extraordinary QE is intramolecular halogen bonding, which can not only effectively enhance ISC by promoting spin–orbit coupling, but also greatly confine motions of excited molecules to restrict non‐radiative pathways. This work provides a reasonable strategy to develop highly efficient UOP materials for practical applications. [ABSTRACT FROM AUTHOR]

Nucleotide‐binding (NB) leucine‐rich repeat (LRR) receptors (NLRs) provide resistance against several plant pathogens. We previously cloned the wheat powdery mildew resistance gene Pm21, which encodes a coiled‐coil (CC) NLR that confers broad‐spectrum resistance against Blumeria graminis f. sp. tritici. Here, we report comprehensive biochemical and functional analyses of Pm21 CC domain in Nicotiana benthamiana. Transient overexpression assay suggested that only the extended CC (eCC, amino acid residues 1–159) domain has cell‐death‐inducing activity, whereas the CC‐containing truncations, including CC‐NB and CC‐NB‐LRR, do not induce cell‐death responses. Coimmunoprecipitation (Co‐IP) assay showed that the eCC domain self‐associates and interacts with the NB and LRR domains in planta. These results imply that the activity of the eCC domain is inhibited by the intramolecular interactions of different domains in the absence of pathogens. We found that the LRR domain plays a crucial role in D491V‐mediated full‐length (FL) Pm21 autoactivation. Some mutations in the CC domain leading to the loss of Pm21 resistance to powdery mildew impaired the CC activity of cell‐death induction. Two mutations (R73Q and E80K) interfered with D491V‐mediated Pm21 autoactivation without affecting the cell‐death‐inducing activity of the eCC domain. Notably, some susceptible mutants harbouring mutations in the CC domain still exhibited cell‐death‐inducing activity. Taken together, these results implicate the CC domain of Pm21 in cell‐death signalling and disease‐resistance signalling, which are potentially independent of each other. [ABSTRACT FROM AUTHOR]

In mitosis, the accurate segregation of sister chromosomes relies on kinetochore, a multiple subunits complex assembled on centromere of each sister chromosome. As a core component of inner kinetochore, CENP‐I plays important functions to mediate kinetochore assembly and supports the faithful chromosome segregation. The structures of the N‐terminus and C‐terminus of CENP‐I homologs in complex with CENP‐H/K have been reported, respectively. Unfortunately, the intramolecular interactions of CENP‐I are poorly understood, and how CENP‐I interacts with CENP‐M remains unknown. Here, we verified a unique helix α11, which forms the intramolecular interactions with N‐terminal HEAT repeats in fungal CENP‐I. Deletion of the helix α11 exposed the hydrophobic surface and resulted in the in vitro protein aggregation of N‐terminal HEAT repeats of fungal CENP‐I. The corresponding helix and its intramolecular interaction are highly conserved in human CENP‐I. Deletion of the corresponding helix in human CENP‐I dramatically reduced the functional activity to interact with CENP‐H and CENP‐M. Mutations of the conserved residues on the helix in human CENP‐I significantly weakened the binding to CENP‐M, but not CENP‐H, in HeLa cells. Therefore, our findings for the first time unveiled a conserved helix of CENP‐I, which is important for the intramolecular interaction and function, and would be helpful for understanding the structure basis of how CENP‐I mediates the kinetochore assembly during cell cycle and mitosis. [ABSTRACT FROM AUTHOR]

The compounds 2-(1-benzofuran-2-yl)-2-oxoethyl 2-nitrobenzoate, C17H11NO6 (I), and 2-(1-benzofuran-2-yl)-2-oxoethyl 2-aminobenzoate, C17H13NO4 (II), were synthesized under mild conditions. Their molecular structures were characterized by both spectroscopic and single-crystal X-ray diffraction analysis. The molecular conformations of both title compounds are generally similar. However, different ortho-substituted moieties at the phenyl ring of the two compounds cause deviations in the torsion angles between the carbonyl group and the attached phenyl ring. In compound (I), the ortho-nitrophenyl ring is twisted away from the adjacent carbonyl group whereas in compound (II), the ortho-aminophenyl ring is almost co-planar with the carbonyl group. In the crystal of compound (I), two C—H...O hydrogen bonds link the molecules into chains propagating along the c-axis direction and the chains are interdigitated, forming sheets parallel to [20-1]. Conversely, pairs of N—H...O hydrogen bonds in compound (II) link inversion-related molecules into dimers, which are further extended by C—H...O hydrogen bonds into dimer chains. These chains are interconnected by π–π interactions involving the furan rings, forming sheets parallel to the ac plane.

The synthesis of a series of palladium(II) complexes of unsymmetrical, hybrid selenoether and telluroether ligands is reported. While the reaction of Pd(II) precursors with symmetrical telluroether ligands containing two coordinating groups results in cleavage of Te–C bond, no such labilisation is observed using unsymmetrical ligands containing one coordinating group. Two novel unsymmetrical selenoether ligands namely, N,N -dimethyl-2-(o -tolylselanyl)aniline (10) and 2-((2,6-dimethylphenyl)selanyl)- N,N -dimethylaniline (11) were synthesized from N,N -dimethylbenzylamine via the ortho -lithiation route. When ligands 10 and 11 were treated with Pd(COD)Cl 2 (COD = 1,5-cyclooctadiene), the reaction afforded novel Pd(II) complexes of the form Pd(2-NMe 2 CH 2 C 6 H 4)(R)SeCl 2 , where R = 2-MeC 6 H 4 (16) and 2,6-MeC 6 H 3 (17) respectively. Similarly, when unsymmetrical telluroether ligands, N,N -dimethyl-2-(phenyltellanyl)aniline (12) , N,N -dimethyl-2-(o-tolyltellanyl)aniline (13), 2-((2,6-dimethylphenyl)tellanyl)- N,N -dimethylaniline (14) and 2-((2,6-diisopropylphenyl)tellanyl)- N,N -dimethylaniline (15), which contain one coordinating group with an sp 3 N-donor atom, were treated with Pd(COD)Cl 2 , the palladium telluroether complexes of the form Pd(2-NMe 2 CH 2 C 6 H 4)(R)TeCl 2 , where R = C 6 H 5 (18), 2-MeC 6 H 4 (19), 2,6-MeC 6 H 3 (20) and 2,6- i PrC 6 H 3 (21) respectively were obtained. The selenoether complexes 16 and 17 and telluroether complexes 18 , 20 and 21 were characterized by single crystal X-ray diffraction studies. In the asymmetric unit of complex 18 , two molecules are present and due to the presence of weak, intermolecular Te⋯Cl interactions, the two molecules exist as symmetrically related dimer. The N-donor substituents, which were involved in intramolecular chalcogen bonding (IChB) with the chalcogen atoms in the free ligand, made six-membered chelating rings in the complexes. Again, when bis(2-phenylazophenyl- C,N ′)selenide 22 was treated with Pd(COD)Cl 2 , it afforded ortho C–H bond activated cyclopalladated complex 24. However, when bis(2-phenylazophenyl- C,N ′)telluride 23 was treated with Pd(COD)Cl 2 , due to strong IChB from two N-donor substituents, the reaction afforded cleaved product, [2-(phenylazo)phenyl-C,N′]tellurenyl chloride, 25. All the metal complexes exhibited significant downfield chemical shifts in 77Se/125Te NMR spectra as compared to the corresponding free ligands. The downfield shifts in the 77Se/125Te NMR signal in the complexes might be attributed to the coordination of the chalcogen atoms to the electropositive Pd(II) center. [ABSTRACT FROM AUTHOR]

A series of heteroleptic diorganotellurides (2-NMe 2 CH 2 C 6 H 4)(R)Te, where R = C 6 H 5 (5), 2-MeC 6 H 4 (6), 2,6-MeC 6 H 3 (7) and 2,6- i PrC 6 H 3 (8) was synthesised from N,N -dimethylbenzylamine via the ortho -lithiation route. Reactions of 5 – 8 with SO 2 Cl 2 followed by alkaline hydrolysis afforded diorganotelluroxides (2-NMe 2 CH 2 C 6 H 4)(R)TeO, where R = C 6 H 5 (10), 2-MeC 6 H 4 (11), 2,6-MeC 6 H 3 (12) and 2,6- i PrC 6 H 3 (13) respectively. A similar alkaline hydrolysis of homoleptic diorganotellurides, {2,6-(Me 2 NCH 2) 2 C 6 H 3 } 2 Te (9), afforded a co-crystal of [{2,6-(Me 2 NCH 2) 2 C 6 H 3 } 2 TeO] (14a) and disordered [{2,6-(Me 2 NCH 2) 2 C 6 H 3 } 2 Te(OH)]Cl (14b) or a completely ordered diorganohydroxytelluronium chloride [{2,6-(Me 2 NCH 2) 2 C 6 H 3 } 2 Te(OH)]Cl (14c). Heteroleptic diorganotellurides 7 – 8 and telluroxides 10 – 14a-b and diorganohydroxytelluronium chloride 14c were characterised by single crystal X-ray diffraction studies. In the molecular structures, the N-donor substituent made five membered chelating ring with the tellurium atom via Te⋯N secondary bonding interactions. Diorganotelluroxide 10 existed in dimeric form exhibiting both intramolecular Te⋯N and intermolecular Te⋯O secondary interactions. Due to the strong intramolecular Te⋯N secondary bonding interactions from the three N-donor substituents, diorganotelluroxide 14a was stabilised in the monomeric form. This is, in fact, the only second example of a discrete monomeric diorganotelluroxide. Again, because of the presence of intramolecular Te⋯N secondary bonding interactions, the diorganotelluroxides 10 – 14a-b and diorganohydroxytelluronium chloride 14c exhibited downfield 125Te NMR chemical shift as compared with the earlier reported oligomeric or polymeric diorganotelluroxides. Image 1 • Synthesis of a series of heteroleptic diorganotellurides containing sp3 N-donor substituents is presented. • Synthesis of heteroleptic diorganotelluroxides is reported by the reactions of diorganotellurides with SO 2 Cl 2 /hydrolysis. • The second example of secondary interaction stabilized monomeric diorganotelluroxide is reported. [ABSTRACT FROM AUTHOR]

Abstract A theoretical study using density functional theory (DFT) is carried out to compare and explain the observed solubility of four antiemetic molecules, namely chlorpromazine, haloperidol, ondansetron and metoclopramide. The COSMO-RS (conductor-like screening model for real solvents) method is used to study the interaction between hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs) of the antiemetic drugs, and their molecular interactions with water (dipole moments, interaction and solvation energies). In addition, the AIM (Atoms in Molecules) method is used to deeply study the hydrogen bonding interaction of the antiemetic drug which was found the most soluble in water, namely the metoclopramide. In fact, results show that atom O42 makes two H-bonds with two different water-oxygen atoms (BCP59 and BCP60). One of them, have another H-bond (BCP62) with the hydrogen H27. This study confirms that two of the three H-bonds with water are more stable than the intramolecular interaction between O9 and H27 (BCP1). These H-bonds are likely responsible of the highest solubility of metoclopramide. Graphical abstract Unlabelled Image Highlights • Theoretical study of the antiemetic solubility • Determination of the bonding type using σ-profile and σ-potential • The interaction mechanism between Metoclopramide and water molecules • The reactivity study of the antiemetic molecules [ABSTRACT FROM AUTHOR]

Oxido bridges commonly form between iron(III) ions, but their bond angles and symmetry vary with the circumstances. A large number of oxido-bridged dinuclear iron(III) complexes have been structurally characterized. Some of them belong to the C2 point group, possessing bent Fe–O–Fe bonds, while some others belong to the Ci symmetry, possessing the linear Fe–O–Fe bonds. The question in this study is what determines the structures and symmetry of oxido-bridged dinuclear iron(III) complexes. In order to gain further insights, three oxido-bridged dinuclear iron(III) complexes were newly prepared with 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen) ligands: [Fe2OCl2(bpy)4][PF6]2 (1), [Fe2O(NO3)2(bpy)4][PF6]2·0.6MeCN·0.2(2-PrOH) (2), and [Fe2OCl2(phen)4][PF6]2·MeCN·0.5H2O (3). The crystal structures of 1, 2, and 3 were determined by the single-crystal X-ray diffraction method, and all of them were found to have the bent Fe–O–Fe bonds. Judging from the crystal structure, some intramolecular interligand hydrogen bonds were found to play an important role in fixing the structures. Additional density functional theory (DFT) calculations were conducted, also for a related oxido-bridged dinuclear iron(III) complex with a linear Fe–O–Fe bond. We conclude that the Fe–O–Fe bridge tends to bend like a water molecule, but is often stretched by interligand steric repulsion, and that the structures are mainly controlled by the intramolecular interligand interactions.

Crystallized aluminium(III) derivative was synthesized and characterized followed by nano alumina from the former reflecting high potential for the dye degradation of congo-red dye and electrochemical sensing of paracetamol [Display omitted] A new homoleptic derivative of aluminium(III) was synthesized quantitatively as white solid by refluxing Al(OPr i) 3 and C 6 H 5 COCH 2 COC 6 H 5 in 1:3 stoichiometry using anhydrous benzene as a solvent for 8 h and was characterized subsequently by relevant spectral tools. The single crystal X-ray diffraction analysis of the complex reveled that new aluminium derivative is triclinic with space group P 1 ¯ and appearing in hexacoordination around aluminium atom. Crystallinity and purity were verified by powder XRD techniques. Further, the complex [(PhCOCHCOPh) 3 Al] was analyzed theoretically using Gaussian software at DFT/B3LYP/LanL2DZ and the results were found in accordance with the experimental data. Findings of intermolecular interactions of [(PhCOCHCOPh) 3 Al] were supported by Hirshfeld surface analysis as it illustrated that packing of the crystal was prominently due to the existence of 51.4% H---H, 21.3% C---H and 16.8% H---C interaction. In addition, nano alumina was also synthesized using this new derivative [(PhCOCHCOPh) 3 Al] as a precursor via well-established sol–gel technique. The obtained nano alumina was assigned as α - phase by powder XRD and its composition and morphology were characterized using FE-SEM and EDX analyses. Subsequently, nano α -alumina was employed as photocatalyst for congo red (CR) dye and was subjected for electrochemical sensing measurements using cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (ESI). The outcomes displayed that the CR dye underwent a remarkable (95%) amount of photodegradation within 10 min on exposure to sunlight. Electrochemical performance of nano α -Al 2 O 3 modified glassy carbon electrode (GCE) demonstrated the oxidation peak at E pa = + 0.2 V in buffer solution with paracetamol and exhibited best sensing performance for the detection of paracetamol. Thus, it might appear as a possible sensor electrode material in the forthcoming investigations. [ABSTRACT FROM AUTHOR]

This article is probably the first such comprehensive review of theoretical methods for estimating the energy of intramolecular hydrogen bonds or other interactions that are frequently the subject of scientific research. Rather than on a plethora of numerical data, the main focus is on discussing the theoretical rationale of each method. Additionally, attention is paid to the fact that it is very often possible to use several variants of a particular method. Both of the methods themselves and their variants often give wide ranges of the obtained estimates. Attention is drawn to the fact that the applicability of a particular method may be significantly limited by various factors that disturb the reliability of the estimation, such as considerable structural changes or new important interactions in the reference system.

Genetic defects in SHANK genes are associated with autism. Deletions and truncating mutations suggest haploinsufficiency for Shank3 as a major cause of disease which may be analyzed in appropriate Shank deficient mouse models. Here we will focus on the functional analysis of missense mutations found in SHANK genes. The relevance of most of these mutations for Shank function, and their role in autism pathogenesis is unclear. This is partly due to the fact that mutations spare the most well studied functional domains of Shank3, such as the PDZ and SAM domains, or the short proline-rich motifs which are required for interactions with postsynaptic partners Homer, Cortactin, dynamin, IRSp53 and Abi-1. One set of mutations affects the N-terminal part, including the highly conserved SPN domain and ankyrin repeats. Functional analysis from several groups has indicated that these mutations (e.g., R12C; L68P; R300C, and Q321R) interfere with the critical role of Shank3 for synapse formation. More recently the structural analysis of the SPN-ARR module has begun to shed light on the molecular consequences of mutations in the SPN of Shank3. The SPN was identified as a Ras association domain, with high affinities for GTP-bound, active forms of Ras and Rap. The two autism related mutations in this part of the protein, R12C and L68P, both abolish Ras binding. Further work is directed at identifying the consequences of Ras binding to Shank proteins at postsynaptic sites.

Two novel hypervalent selenium(IV) compounds stabilized by intramolecular interactions, namely 6‐phenyl‐6,7‐dihydro‐5H‐2,3‐dioxa‐2aλ4‐selenacyclopenta[hi]indene, C14H12O2Se, 14, and 5‐phenyl‐5,6‐dihydro‐4H‐benzo[c][1,2]oxaselenole‐7‐carbaldehyde, C14H12OSe2, 15, have been synthesized by the reaction of 2‐chloro‐1‐formyl‐3‐(hydroxymethylene)cyclohexene with in‐situ‐generated disodium diselenide (Na2Se2). The title compounds were characterized by FT–IR spectroscopy, ESI–MS, and single‐crystal X‐ray diffraction studies. For 14, there is whole‐molecule disorder, with occupancies of 0.605 (10) and 0.395 (10), a double bond between C and Se, and the five‐membered selenopentalene rings are coplanar. The packing is stabilized by π–π stacking interactions involving one of the five‐membered Se/C/C/C/O rings [centroid–centroid (Cg...Cg) distance = 3.6472 (18) Å and slippage = 1.361 Å], as well as C—H...π interactions involving a C—H group and the phenyl ring. In addition, there are bifurcated C—H...Se,O interactions which link the molecules into ribbons in the c direction. For 15, the C—Se bond lengths are longer than those of 14. The two five‐membered rings are coplanar. There are no π–π or C—H...π interactions; however, molecules are linked by C—H...O interactions into centrosymmetric dimers, with graph‐set notation R22(16). In the structures of two chalcogenapentalene derivatives, 6‐phenyl‐6,7‐dihydro‐5H‐2,3‐dioxa‐2aλ4‐selenacyclopenta[hi]indene and 5‐phenyl‐5,6‐dihydro‐4H‐benzo[c][1,2]oxaselenole‐7‐carbaldehyde, the former is stabilized by Se—O bonds, while in the latter, there is both an Se—Se bond and an Se...O interaction, which helps in the stabilization of the structure. [ABSTRACT FROM AUTHOR]

A convenient approach for the synthesis of alicyclic selenospirocycles, 24 and 25, stabilized by intramolecular chalcogen bonding (IChB) is reported by the reaction of 5‐alkyl‐2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene derivatives {alkyl=H (22), Me (23)} with in situ generated disodium diselenide (Na2Se2). However, when 2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene, 22 is condensed with aniline or 4‐methoxyaniline and the resulting Schiff bases 26 and 27 are subjected to identical reactions, the Schiff bases undergo cyclisation to afford brightly colored, fused 1,6‐diaza‐6a‐selenapentalene derivatives 28–29, instead of the expected selenospirocycles. The aromatic nucleophilic substitution (SNAr) reaction of N‐(2‐bromo‐3‐nitrobenzyl)naphthylamine, 33 with nBuSeLi affords N‐[2‐(butylselanyl)‐3‐nitrobenzyl]naphthylamine, 34. The bromination of 34 results in the formation of cyclic isoselenazolines, 35. Selenospirocycles 24 and 25, 1,6‐diaza‐6a‐selenapentalenes 28 and 29 and isoselenazoline 35 are authenticated by single‐crystal X‐ray diffraction studies. Compounds 24, 25 and 35 are stabilized by intramolecular secondary interactions. The reaction of 5‐alkyl‐2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene derivatives (alkyl=H, Me) with in situ generated disodium diselenide (Na2Se2) affords alicyclic selenospirocycles. However, a similar reaction of the Schiff base derivatives of 2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene with Na2Se2 leads to the formation of highly colored azapentalenes. The attempted synthesis of selenospirocycle from N‐[2‐(butylselanyl)‐3‐nitrobenzyl]naphthylamine results in the formation of isoselenazolines. [ABSTRACT FROM AUTHOR]

The total electron density (ED) along the λ2‐eigenvector is decomposed into contributions which either facilitate or hinder the presence of an electron density bridge (DB, often called an atomic interaction line or a bond path). Our FALDI‐based approach explains a DB presence as a result of a dominating rate of change of facilitating factors relative to the rate of change of hindering factors; a novel and universal criterion for a DB presence is, thus, proposed. Importantly, facilitating factors show, in absolute terms, a concentration of ED in the internuclear region as commonly observed for most chemical bonds, whereas hindering factors show a depletion of ED in the internuclear region. We test our approach on four intramolecular interactions, namely (i) an attractive classical H‐bond, (ii) a repulsive O⋅⋅⋅O interaction, (iii) an attractive Cl⋅⋅⋅Cl interaction, and (iv) an attractive CH⋅⋅⋅HC interaction. (Dis)appearance of a DB is (i) shown to be due to a "small" change in molecular environment and (ii) qualitatively and quantitatively linked with specific atoms and atom‐pairs. The protocol described is equally applicable (a) to any internuclear region, (b) regardless of what kind of interaction (attractive/repulsive) atoms are involved in, (c) at any level of theory used to compute the molecular structure and corresponding wavefunction, and (d) equilibrium or nonequilibrium structures. Finally, we argue for a paradigm shift in the description of chemical interactions, from the ED perspective, in favor of a multicenter rather than diatomic approach in interpreting ED distributions in internuclear regions. © 2018 Wiley Periodicals, Inc. A novel quantum chemical function is introduced which can be used to study and understand the presence or absence of a density bridge in an internuclear region. The CP(r) function uses the gradients of bonding, nonbonding, and antibonding density contributions from the FALDI density decomposition scheme to assess the origin and nature of density bridges for intermolecular and intramolecular interactions in equilibrium and nonequilibrium structures. [ABSTRACT FROM AUTHOR]

Ubiquitination, the covalent attachment of ubiquitin to proteins, by E3 ligases of the HECT (homologous to E6AP C terminus) family is critical in controlling diverse physiological pathways. Stringent control of HECT E3 ligase activity and substrate specificity is essential for cellular health, whereas deregulation of HECT E3s plays a prominent role in disease. The cell employs a wide variety of regulatory mechanisms to control HECT E3 activity and substrate specificity. Here, we summarize the current understanding of these regulatory mechanisms that control HECT E3 function. Substrate specificity is generally determined by interactions of adaptor proteins with domains in the N-terminal extensions of HECT E3 ligases. These N-terminal domains have also been found to interact with the HECT domain, resulting in the formation of inhibitory conformations. In addition, catalytic activity of the HECT domain is commonly regulated at the level of E2 recruitment and through HECT E3 oligomerization. The previously mentioned regulatory mechanisms can be controlled through protein-protein interactions, post-translational modifications, the binding of calcium ions, and more. Functional activity is determined not only by substrate recruitment and catalytic activity, but also by the type of ubiquitin polymers catalyzed to the substrate. While this is often determined by the specific HECT member, recent studies demonstrate that HECT E3s can be modulated to alter the type of ubiquitin polymers they catalyze. Insight into these diverse regulatory mechanisms that control HECT E3 activity may open up new avenues for therapeutic strategies aimed at inhibition or enhancement of HECT E3 function in disease-related pathways. [ABSTRACT FROM AUTHOR]

A chlorophyll- a derivative homo-dimer covalently linked with a flexible methylene-amino-methylene group at the 3-position was benzoylated to give the dyad bearing a CH 2 N(COPh)CH 2 linker. The synthetic dyad with the relatively rigid spacer showed red-shifted visible absorption bands and was oxidized more readily, in comparison with the corresponding monomer. The optical and electrochemical properties of the dimer are ascribable to the partial π-stacking of chlorin moieties in the benzoylated dyad, mimicking the special dimeric species in reaction centers of photochemical systems in natural phototrophs. [ABSTRACT FROM AUTHOR]

Genetic defects in SHANK genes are associated with autism. Deletions and truncating mutations suggest haploinsufficiency for Shank3 as a major cause of disease which may be analyzed in appropriate Shank deficient mouse models. Here we will focus on the functional analysis of missense mutations found in SHANK genes. The relevance of most of these mutations for Shank function, and their role in autism pathogenesis is unclear. This is partly due to the fact that mutations spare the most well studied functional domains of Shank3, such as the PDZ and SAM domains, or the short proline-rich motifs which are required for interactions with postsynaptic partners Homer, Cortactin, dynamin, IRSp53 and Abi-1. One set of mutations affects the N-terminal part, including the highly conserved SPN domain and ankyrin repeats. Functional analysis from several groups has indicated that these mutations (e.g., R12C; L68P; R300C, and Q321R) interfere with the critical role of Shank3 for synapse formation. More recently the structural analysis of the SPN-ARR module has begun to shed light on the molecular consequences of mutations in the SPN of Shank3. The SPN was identified as a Ras association domain, with high affinities for GTP-bound, active forms of Ras and Rap. The two autism related mutations in this part of the protein, R12C and L68P, both abolish Ras binding. Further work is directed at identifying the consequences of Ras binding to Shank proteins at postsynaptic sites. [ABSTRACT FROM AUTHOR]

In order to test the possible presence of the intramolecular interactions O → M in the group 14 elements and its consequences on the geometry, the 2-methoxybenzyl chlorine was reacted with magnesium and subsequently with the group 14 chlorides, Ph 3 MCl, to produce the organometallic compounds (2-CH 3 OC 6 H 4 )CH 2 MPh 3 [M = Si ( 1 ), Ge ( 2 ) and Pb ( 3 )]. The compounds were fully characterized by elemental analysis, infrared spectroscopy, mass spectrometry (FAB + ), and multinuclear ( 1 H, 13 C, 29 Si, 207 Pb) NMR spectroscopy. The compounds 1 and 2 also were investigated by single crystal X-ray diffraction analysis, they are isostructural with a triclinic crystal system and P -1 space group, exhibiting a distorted tetrahedral environment. The possible intramolecular O → M distances in 1 and 2 are 3.810 Å and 3.802 Å respectively, and represent more than the 100% of the sum of the appropriate Van der Waal’s radii. By comparison, in the previously reported tin analogous compound, that is not part of this work, the intramolecular distance O → Sn is ∼80% of the sum of the Van der Waal’s radii. The molecular structures of the four organometallic complexes were fully studied within the Density Functional Theory formalism. [ABSTRACT FROM AUTHOR]