Long non-coding RNA MM2P suppresses M1-polarized macrophages-mediated excessive inflammation to prevent sodium taurocholate-induced acute pancreatitis by blocking SHP2-mediated STAT3 dephosphorylation.

M1 macrophage-mediated excessive inflammatory response plays a key role in the onset and progression of acute pancreatitis (AP), and this study aimed to investigate the role and underlying mechanisms by which the macrophage polarization-related long noncoding RNA (lncRNA) MM2P participated in the regulation of AP progression. By performing quantitative reverse-transcription PCR (qRT-PCR) assay, lncRNA MM2P was found to be downregulated in both sodium taurocholate-induced AP model mice tissues and lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and gain-of-function experiments confirmed that overexpression of lncRNA MM2P counteracted inflammatory responses, reduced macrophage infiltration and facilitated M1-to-M2 transformation of macrophages to ameliorate AP development in vitro and in vivo. Further mechanical experiments revealed that lncRNA MM2P inhibited Src homology 2 containing protein tyrosine phosphatase 2 (SHP2)-mediated signal transducer and activator of transcription 3 (STAT3) dephosphorylation to activate the STAT3 signaling, and silencing of SHP2 suppressed M1 type skewing in LPS-induced RAW264.7 cells. Interestingly, our rescuing experiments verified that lncRNA MM2P-induced suppressing effects on M1-polarization of LPS-treated RAW264.7 cells were abrogated by co-treating cells with STAT3 inhibitor stattic. Collectively, our data for the first time revealed that lncRNA MM2P suppressed M1-polarized macrophages to attenuate the progression of sodium taurocholate-induced AP, and lncRNA MM2P might be an ideal biomarker for AP diagnosis and treatment.

Reversible Single-Crystal-to-Single-Crystal Transformation of a Coordination Polymer through Solar-Switchable Cycloaddition and Cycloreversion Reaction.

Reversible covalent reactions within crystalline complexes are powerful tools for the design and developing of new generation of reusable smart materials. In this work, a unique photoreactive olefin-containing metal-organic coordination polymer [Ag2(2,3-ppe)2(1,3-bdc)]n (1) was prepared by the hydrothermal reaction between AgNO3, 1-(2-pyridyl)-2-(3-pyridyl)ethylene (2,3-ppe), and 1,3-benzenedicarboxylic acid (1,3-H2bdc). When exposed to sunlight, 1 can undergo single-crystal-to-single-crystal (SCSC) transformation to form [Ag2(dpdpcb)(1,3-bdc)]n (1a, dpdpcb = 1,3-di(2-pyridyl)-2,4-di(3-pyridyl)cyclobutane) through a [2 + 2] cycloaddition reaction. 1a can regenerate into 1 via the cycloreversion reaction based on the thermal effect of sunlight. Such a metal-organic complex exhibits interesting fluorescence switching behavior during the unprecedented fully solar-controlled reversible SCSC reaction, which makes it possible to be applied to the fields of optical memory storage and anti-counterfeiting.

Topological structural transformation of a two-dimensional coordination polymer via single-crystal to single-crystal photoreaction.

Photoreactive coordination polymers are particularly important media for the implementation of highly-selective photoreactions and creation of photoresponsive intelligent materials and devices. Herein, a two-dimensional (2D) photoreactive coordination polymer, formulated as [Cd(pha)(3,3'-bpe)]n (1) was prepared through the hydrothermal reaction between Cd(NO3)2·4H2O, phthalic acid (H2pha) and 1,2-bis(3-pyridyl)ethylene (3,3'-bpe). Upon exposure to 365 nm UV light, the 1H NMR spectroscopy and single crystal X-ray diffraction analysis results indicated that 1 can undergo a [2 + 2] photocycloaddition reaction and thus form a new coordination polymer [Cd(pha)(3,3'-tpcb)0.5]n (1a) through single-crystal to single-crystal (SCSC) transformation. Accompanied by the SCSC photoreaction, the 2D sql net of 1 converted into a 2D binodal network of 1a with the rare (324·627)(326272) topology. The SCSC transformation from 1 to 1a also exhibits an interesting photocontrolled fluorescence. The unique photoinduced structural change and fluorescence quenching of 1 makes it a potential intelligent material for optical anti-counterfeiting, fluorescence sensors and other fields.

Crystallographic Visualization of a Guest-Induced Solar-Driven Cycloaddition Reaction Based on a Recyclable Nonporous Coordination Polymer.

Stimuli-responsive solids with adjustable photophysical properties are particularly attractive because they can be used as smart materials in anticounterfeiting, information storage, holographic imaging, and other fields. Herein, we report a unique nonporous coordination polymer, {[Ag(3,3'-dpe)](2,2'-Hbpdc)}n (1; 3,3'-dpe = 1,2-dipyridin-3-ylethene and 2,2'-H2bpdc = 2,2'-biphenyldicarboxylic acid), that can convert to an extremely photoreactive compound, 1·H2O·MeCN (MeCN = acetonitrile), through guest capture. Upon irradiation of sunlight, 1·H2O·MeCN can transform to {[Ag(3,3'-tpcb)0.5](2,2'-Hbpdc)(H2O)(MeCN)}n (2·H2O·MeCN; 3,3'-tpcb = 1,2,3,4-tetrapyridin-3-ylcyclobutane). 2·H2O·MeCN can lose its solvent molecules to form 2 and further return to 1 at high temperature. Accompanied by direct visualization based on multistep single-crystal-to-single-crystal conversions, the recyclable crystalline solid exhibits remarkable fluorescence changes, which makes it a supramolecular switch for application in multiple anticounterfeiting.

Reversible single-crystal-to-single-crystal conversion of a photoreactive coordination network for rewritable optical memory storage.

Reversible single-crystal-to-single-crystal photocyclization-cycloreversion reaction of a stilbene-based coordination network exhibits a conspicuous fluorescence change. The controllable fluorescence and high fatigue resistance feature of this bistable material make it a single-crystalline device for applications in rewritable optical memory storage systems.

Regioselective Photochemical Cycloaddition Reactions of Diolefinic Ligands in Coordination Polymers.

The pure diolefinic ligand 1,4-bis(pyridin-4-yl)-1,3-butadiene (bpbde) is photostable in the crystalline state. With the assistance of coordination-driven metal-organic assemblies, the photoreactivity of this diolefinic ligand can be significantly enhanced. A hydrothermal reaction of bpbde with Cd(NO3 )2 ⋅4 H2 O and the auxiliary ligand adipic acid resulted in the formation of a two-dimensional photoreactive coordination polymer (CP), [Cd(adipate)(bpbde)]n (1). When the aliphatic carboxylic acid was replaced by pimelic acid, another photoreactive CP [Cd(pimelate)(bpbde)]n (2) with a three-dimensional framework was obtained. With irradiation of 365 nm UV light, the bpbde ligands in crystalline 1 and 2 underwent a regioselective photochemical [2+2] cycloaddition reaction and converted to 3,4,7,8-tetra(pyridin-4-yl)tricyclo[4.2.0.02,5 ]octane (tptco) and 1,3-bis(pyridin-4-yl)-2,4-bis(2-(pyridin-4-yl)vinyl)cyclobutane (bpbpvcb), respectively. The results provide an interesting insight into the rational design of highly regio- or stereoselective photocatalytic reactions for the formation of special organic molecules.

Synthesis, structure and photoluminescence properties of a three-dimensional cadmium(II) (4,5)-connected coordination network.

The assembly of coordination polymers from metal ions and organic moieties is currently attracting considerable attention in crystal engineering due to their intriguing architectures and potential applications as functional materials. A new coordination polymer, namely poly[[µ2-trans-1,2-bis(pyridin-3-yl)ethylene-κ2N:N']bis(µ4-4,4'-oxydibenzoato-κ6O:O,O':O'':O'',O''')dicadmium(II)], [Cd2(C14H8O5)2(C12H10N2)]n or [Cd2(4,4'-OBB)2(3,3'-BPE)]n, has been synthesized by the the self-assembly of Cd(NO3)2·4H2O, 4,4'-oxydibenzoic acid (4,4'-H2OBB) and trans-1,2-bis(pyridin-3-yl)ethene (3,3'-BPE) under hydrothermal conditions. The title compound was structurally characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction analysis. Each CdII centre is coordinated by six carboxylate O atoms from four different 4,4'-OBB2- ligands and by one pyridyl N atom form a 3,3'-BPE ligand. Adjacent crystallographically equivalent CdII ions are bridged by 4,4'-OBB2- ligands, affording a two-dimensional [Cd(4,4'-OBB)]n net extending in the ac plane. Neighbouring [Cd(4,4'-OBB)]n nets are interlinked by 3,3'-BPE along the b axis to form a three-dimensional (3D) [Cd2(4,4'-OBB)2(3,3'-BPE)]n coordination network. In the network, each CdII centre is linked by four different 4,4'-OBB2- ligands and one 3,3'-BPE ligand. Meanwhile, each 4,4'-OBB2- ligand connects four separate CdII ions. Therefore, if the 4,4'-OBB2- ligands and CdII ions are considered as 4- and 5-connecting nodes, the structure of the title compound can be simplified as a 3D (4,5)-connected binodal framework with the rare (4462)(4466) TCS topology (Pearson, 1985; Blake et al., 2011). The thermal stability and photoluminescence properties of the title compound have also been investigated.

Construction and photoluminescence properties of a three-dimensional ZnII coordination network based on naphthalene-1,4-dicarboxylic acid and 1,6-bis(pyridin-3-yl)-1,3,5-hexatriene.

In recent years, coordination polymers constructed from multidentate carboxylate and pyridyl ligands have attracted much attention because these ligands can adopt a rich variety of coordination modes and thus lead to the formation of crystalline products with intriguing structures and interesting properties. A new coordination polymer, namely poly[[µ2-1,6-bis(pyridin-3-yl)-1,3,5-hexatriene-κ2N:N'](µ3-naphthalene-1,4-dicarboxylato-κ4O1,O1':O4:O4')zinc(II)], [Zn(C12H6O4)(C16H14N2)]n, has been prepared by the self-assembly of Zn(NO3)2·6H2O, naphthalene-1,4-dicarboxylic acid (1,4-H2ndc) and 1,6-bis(pyridin-3-yl)-1,3,5-hexatriene (3,3'-bphte) under hydrothermal conditions. The title compound has been structurally characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction and single-crystal X-ray diffraction analysis. Each ZnII ion is six-coordinated by four O atoms from three 1,4-ndc2- ligands and by two N atoms from two 3,3'-bphte ligands, forming a distorted octahedral ZnO4N2 coordination geometry. Pairs of ZnII ions are linked by 1,4-ndc2- ligands, leading to the formation of a two-dimensional square lattice (sql) layer extending in the ab plane. In the crystal, adjacent layers are further connected by 3,3'-bphte bridges, generating a three-dimensional architecture. From a topological viewpoint, if each dinuclear zinc unit is considered as a 6-connected node and the 1,4-ndc2- and 3,3'-bphte ligands are regarded as linkers, the structure can be simplified as a unique three-dimensional 6-connected framework with the point symbol 446108. The thermal stability and solid-state photoluminescence properties have also been investigated.

Substituent effects of two isophthalate derivatives on the construction of cadmium coordination polymers incorporating a dipyridyl ligand.

In recent years, the design and construction of crystalline coordination complexes by the assembly of metal ions with multitopic ligands have attracted considerable attention because of the unique architectures and potential applications of these compounds. Two new coordination polymers, namely poly[[µ-trans-1-(2-aminopyridin-3-yl)-2-(pyridin-4-yl)ethene-κ2N:N'](µ3-5-methylisophthalato-κ4O1,O1':O3:O3')cadmium(II)], [Cd(C9H6O4)(C12H11N3)]n or [Cd(5-Me-ip)(2-NH2-3,4-bpe)]n, (I), and poly[[µ-trans-1-(2-aminopyridin-3-yl)-2-(pyridin-4-yl)ethene-κ2N:N'](µ2-5-hydroxyisophthalato-κ4O1,O1':O3:O5)cadmium(II)], [Cd(C8H4O5)(C12H11N3)]n or [Cd(5-HO-ip)(2-NH2-3,4-bpe)]n, (II), have been prepared hydrothermally by the self-assembly of Cd(NO3)2·4H2O and trans-1-(2-aminopyridin-3-yl)-2-(pyridin-4-yl)ethene (2-NH2-3,4-bpe) with two similar dicarboxylic acids, i.e. 5-methylisophthalic acid (5-Me-H2ip) and 5-hydroxyisophthalic acid (5-HO-H2ip). The coordination network of (I) is a two-dimensional sql net parallel to (101). Adjacent sql nets are further linked to form a three-dimensional supramolecular framework via hydrogen-bonding interactions. Compound (II) is a two-dimensional (3,5)-connected coordination network parallel to (010) with the point symbol (63)(55647). As the other reactants and reaction conditions are the same, the structural differences between (I) and (II) are undoubtedly determined by the different substituent groups in the 5-position of isophthalic acid. Both (I) and (II) exhibit good thermal stabilities and photoluminescence properties.

Covalent switching, involving divinylbenzene ligands within 3D coordination polymers, indicated by changes in fluorescence.

Reversible cycloaddition reactions between 1,4-bis[2-(3-pyridyl)ethenyl]benzene and its photodimers were performed within a pair of three-dimensional coordination polymers with retention of single crystal character. In each case, switching between two crystalline forms could be followed by monitoring the flourescence behaviour.

Controllable Fluorescence Switching of a Coordination Chain Based on the Photoinduced Single-Crystal-to-Single-Crystal Reversible Transformation of a syn-[2.2]Metacyclophane.

The observation of a reversible chemical transformation corresponding to an external stimulus in the solid state is intriguing in the exploration of smart materials, which can potentially be applied in molecular machines, molecular switches, sensors, and data storage devices. The solid-state photodimerization reaction of 1,3-bis[2-(4-pyridyl)ethenyl]benzene (1,3-bpeb) in a one-dimensional coordination polymer {[Cd2(1,3-bpeb)2(4-FBA)4]·H2O}n (4-FBA = 4-fluorobenzoate) with 365 nm UV light afforded syn-tetrakis(4-pyridyl)-1,2,9,10-diethano[2.2]metacyclophane (syn-tpmcp) in quantitative yield via a single-crystal-to-single-crystal (SCSC) transformation. Upon irradiation with 254 nm UV light, an SCSC conversion from syn-tpmcp to 1,3-bpeb was also achieved in quantitative yield within the syn-tpmcp-supported coordination polymer {[Cd2(syn-tpmcp)(4-FBA)4]·H2O}n. In particular, accompanied by the reversible transformation between 1,3-bpeb and syn-tpmcp, the coordination chain exhibits photocontrollable fluorescence-switching behavior, which makes this intelligent material an appealing candidate for practical applications.

A three-dimensional cadmium coordination polymer based on 1,4-bis(1,2,4-triazol-1-yl)but-2-ene and benzene-1,3,5-tricarboxylic acid.

The CdII three-dimensional coordination poly[[[µ4-1,4-bis(1,2,4-triazol-1-yl)but-2-ene]bis(µ3-5-carboxybenzene-1,3-dicarboxylato)dicadmium(II)] dihydrate], {[Cd2(C9H4O6)2(C8H10N6)]·2H2O}n, (I), has been synthesized by the hydrothermal reaction of Cd(NO3)2·4H2O, benzene-1,3,5-tricarboxylic acid (1,3,5-H3BTC) and 1,4-bis(1,2,4-triazol-1-yl)but-2-ene (1,4-btbe). The IR spectrum suggests the presence of protonated carboxylic acid, deprotonated carboxylate and triazolyl groups. The purity of the bulk sample was confirmed by elemental analysis and X-ray powder diffraction. Single-crystal X-ray diffraction analysis reveals that the CdII ions adopt a five-coordinated distorted trigonal-bipyramidal geometry, coordinated by three O atoms from three different 1,3,5-HBTC2- ligands and two N atoms from two different 1,4-btbe ligands; the latter are situated on centres of inversion. The CdII centres are bridged by 1,3,5-HBTC2- and 1,4-btbe ligands into an overall three-dimensional framework. When the CdII centres and the tetradentate 1,4-btbe ligands are regarded as nodes, the three-dimensional topology can be simplified as a binodal 4,6-connected network. Thermogravimetric analysis confirms the presence of lattice water in (I). Photoluminescence studies imply that the emission of (I) may be ascribed to intraligand fluorescence.

Poly[di-µ-aqua-µ-1,2-bis(pyridin-4-yl)ethene-κ2N:N'-tetrakis(4-iodobenzoato-κ2O,O')dicadmium].

Colourless crystals of the title compound, [Cd(2)(C(7)H(4)IO(2))(4)(C(12)H(10)N(2))(H(2)O)(2)](n), were obtained by the self-assembly of Cd(NO(3))(2)·4H(2)O, 1,2-bis(pyridin-4-yl)ethene (bpe) and 4-iodobenzoic acid (4-IBA). Each Cd(II) atom is seven-coordinated in a pentagonal-bipyramidal coordination environment by four carboxylate O atoms from two different 4-IBA ligands, two O atoms from two water molecules and one N atom from a bpe ligand. The Cd(II) centres are bridged by the aqua molecules and bpe ligands, which lie across centres of inversion, to give a two-dimensional net. Topologically, taking the Cd(II) atoms as nodes and the µ-aqua and µ-bpe ligands as linkers, the two-dimensional structure can be simplified as a (6,3) network.

catena-Poly[[[tetra-aqua-nickel(II)]-µ-4,4'-bipyridyl-κN:N'] 3,3'-(p-phenyl-ene)diacrylate].

In the title compound, {[Ni(C(10)H(8)N(2))(H(2)O)(4)](C(12)H(8)O(4))}(n), the Ni(II), 4,4'-bipyridyl (bipy) and 3,3'-(p-phenyl-ene)diacrylate (L(2-)) moieties are situated on inversion centres. The bipy ligands bridge Ni(II) ions into positively charged polymeric chains along [101]. The Ni(II) atom is coordinated by two N atoms from two bipy ligands and four water mol-ecules in a distorted octa-hedral geometry. L(2-) anions inter-act with the polymeric chains via O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular network.

Single-crystal to single-crystal transformation of 1D coordination polymer via photochemical [2+2] cycloaddition reaction.

Photochemical single-crystal to single-crystal transformation of one 1D polymer [Cd(bpe)(CBA)(2)](n) afforded a new 1D polymer [Cd(rctt-tpcb)(0.5)(CBA)(2)](n) which underwent hydrothermal reaction in strong acidic solution to form a 3D coordination polymer {[Cd(rtct-tpcb)Cl(2)]·2H(2)O}(n).

Poly[(µ(2)-1,3-di-4-pyridyl-propane)(µ(3)-1,3-phenyl-enediacetato)-cadmium].

In the title compound, [Cd(C(10)H(8)O(4))(C(13)H(14)N(2))](n), two symmetry-related Cd atoms are bridged by two carboxyl-ate O atoms into a binuclear Cd(2) subunit around an inversion center. The Cd atom has a distorted penta-gonal-bipyramidal environment, defined by five O atoms from three different 1,3-phenylendiacetate (1,3-pda) ligands and two N atoms from two 1,3-di-4-pyridyl-propane (bpp) ligands. Each Cd(2) subunit is linked to four different Cd(2) subunits by four 1,3-pda ligands and four bpp ligands, forming a two-dimensional network with rhombic grids (12.50 × 12.50 Å(2)) extending along the ab plane.

catena-Poly[[[bis-(4-bromo-benzoato-κO)zinc]-µ-1,2-bis-(4-pyrid-yl)ethene-κN:N'] acetonitrile monosolvate].

In the title coordination compound, {[Zn(C(7)H(4)BrO(2))(2)(C(12)H(10)N(2))]·CH(3)CN}(n), the Zn(II) atom is four-coordinated in a distorted tetra-hedral environment by two carboxyl-ate O atoms from two different 4-bromo-benzoate (bpe) ligands and two N atoms from two symmetry-related 1,2-bis-(4-pyrid-yl)ethene ligands. The Zn(II) atoms are bridged by the bpe ligands, which lie across centres of inversion, forming a zigzag chain along [001]. The void space of each unit cell is occupied by an acetonitrile solvent mol-ecule, which is connected to the complex mol-ecule by a weak C-H⋯N hydrogen bond.

Benzene-1,3-dicarb-oxy-lic acid-1,2-bis-(4-pyrid-yl)ethene (1/1).

In the title compound, C(12)H(10)N(2)·C(8)H(6)O(4), the asymmetric unit contains two halves of 1,2-bis-(4-pyrid-yl)ethene (bpe) mol-ecules and one benzene-1,3-dicarb-oxy-lic acid (1,3-H(2)BDC) mol-ecule. These bpe and 1,3-H(2)BDC mol-ecules are linked by classical O-H⋯N hydrogen bonds, forming an extended one-dimensional zigzag chain. Each chain is further linked with neighboring ones by π-π inter-actions between the pyridine and aromatic rings [centroid-centroid distances = 3.9306 (15) Å] and the pyridine rings of pairs of symmetry-related mol-ecules [centroid-centroid distances = 3.5751 (15), 3.7350 (15) and 3.6882 (15) Å], with the formation of a three-dimensional supra-molecular framework.

Construction of [Ag2X2]-based complexes from reactions of Ag(I) salts with N-diphenylphosphanylmethyl-4-aminopyridine: isolation, structures, and luminescent properties.

Reactions of N-diphenylphosphanylmethyl-4-aminopyridine (dppmapy) with K[Ag(CN)(2)], Ag(dca) (dca = dicyanamide), AgSCN, AgCl, AgBr or AgI gave rise to six [Ag(2)X(2)]-based (X = CN(-), dca, SCN(-), Cl(-), Br(-) and I(-)) compounds, [{Ag(2)(CN)(2)(dppmapy)}.0.5CHCl(3)](n) (1), [Ag(2)L(2)(dppmapy)(2)](n) (2: L = dca; 3: L = SCN), [{Ag(2)L(2)(dppmapy)(2)}.sol](n) (4: L = Cl, sol = 0.5MeOH.0.5CH(2)Cl(2); 5: L = Br, sol = 2CHCl(3)), and [Ag(2)I(2)(dppmapy)(4)].3MeOH (6). Complexes 1-6 were characterized by elemental analysis, IR, powder X-ray diffraction (PXRD), and single crystal X-ray diffraction. Compound 1 has a one-dimensional (1D) spiral chain constructed by bridging the [(CN)Ag(mu-CN)Ag] fragments via dppmapy ligands. In 2, 3 and 4, each [Ag(2)X(2)] (X = dca, SCN, Cl) fragment is linked by dppmapy bridges to the other two equivalent ones to form a 1D chain containing 16-membered rings (2) or a 1D double chain containing 20-membered rings (3) or a 1D spiral chain containing 20-membered rings (4). Compound 5 possesses a two dimensional (2D) (4,4) network consisting of 36-membered metallomacrocycles in which each [Ag(2)Br(2)] fragment acts as a unique planar four-connecting node to link the other four equivalent ones via dppmapy bridges. Complex 6 has a [Ag(2)I(2)] unit with a pair of monodentate dppmapy ligands coordinated at each Ag center. The photoluminescent properties of 1-6 in the solid state at ambient temperature were also investigated.