Structure Of Bis Research Articles

Revisiting the early days of conjugated polyyne synthesis. Syntheses and structures of Bis(triethylsilyl) Polyynediyl Adducts Et3Si(C[tbnd]C)nSiEt3 previously regarded as Unisolable (n = 6, 8, 12)

An overview of bis(trialkylsilyl) polyynediyl adducts R3Si(CC)nSiR3 with n ≥ 5 is followed by syntheses of TESCxTES where x = 8, 12, 16, and 24 (TES = SiEt3; x = 2n). In a seminal 1972 study, the last three were presented as too unstable to isolate and thus only characterized by UV-visible spectroscopy. Although not a rational route, TESC24TES is consistently obtained from the reaction of trans-(C6F5)(p-tol3P)2Pt(CC)5SiEt3 and crude HC8TES under Hay oxidative cross coupling conditions. The latter contains some HC8H and TESC8TES. Hay oxidative homocouplings of HC4TES and crude HC8TES afford TESC8TES (83%) and TESC16TES (5%). A Cadiot-Chodkiewicz reaction of BrC4Br and HC4TES (2 equiv) yields TESC12TES (11%). All of these compounds are crystalline, and the crystal structures of TESC8TES and TESC16TES are determined. The 13C{1H} NMR and UV-visible properties are also compared.

Understanding the Adsorption Mechanism of BTPA, DEPA, and DPPA in the Separation of Malachite from Calcite and Quartz: DFT and Experimental Studies

The relationship between the structure of bis (2,4,4-trimethylpentyl) phosphinic acid (BTPA), diethyl phosphinic acid (DEPA), and diphenyl phosphinic acid (DPPA) on the flotation performance of malachite was investigated. Through a series of flotation experiments, density functional theory (DFT) calculations, and surface analysis methods, we aimed to deeply understand the microscopic mechanism of the interactions between these collectors and the malachite surface. The experimental results showed that BTPA exhibited excellent selectivity and flotation performance for malachite in the pH range of 5.0–11.0, significantly better than DEPA and DPPA. Surface analysis evidence from X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) further confirmed the chemical adsorption characteristics of BTPA on the malachite surface. DFT calculations revealed that the adsorption capacity of BTPA on the malachite surface exceeds that of DEPA and DPPA. Electron transfer analysis, especially through frontier molecular orbital theory, differential charge density, PDOS, and COHP analysis, indicated that the charge transfer process from the s orbitals of oxygen atoms in the collectors to the d orbitals of copper atoms on the mineral surface is the decisive factor for the adsorption strength.

From field-induced to zero-field SMMs associated with open/closed structures of bis(ZnDy) tetranuclear complexes: a combined magnetic, theoretical and optical study.

We have prepared a bis(compartmental) Mannich base ligand H4L (1,4,8,11-tetraaza-1,4,8,11-tetrakis(2-hydroxy-3-methoxy-5-methylbenzyl)cyclotetradecane) specifically designed to obtain bis(TMIILnIII) tetranuclear complexes (TM = transition metal). In this regard, we have succeeded in obtaining three new complexes of the formula [Zn2(μ-L)(μ-OAc)Dy2(NO3)2]·[Zn2(μ-L)(μ-OAc)Dy2(NO3)(OAc)]·4CHCl3·2MeOH (1) and [TM2(μ-H2L)2(μ-succinate)Ln2(NO3)2] (NO3)2·2H2O·6MeOH (TMII = Zn, LnIII = Dy (2); TMII = Co, LnIII = Dy (3)). Compound 1 contains two different bis(ZnDy) tetranuclear molecules that cocrystallize in the structure, in which acetato bridging ligands connect the ZnII and DyIII ions within each ZnDy subunit. This compound does not exhibit slow magnetic relaxation at zero field, but it is activated in the presence of an applied dc magnetic field and/or by Dy/Y magnetic dilution, showing two relaxation processes corresponding to each of the two different bis(ZnDy) units found in the structure. As revealed by the theoretical calculations, magnetic relaxation in 1 is single-ion in origin and takes place through the first excited state of each DyIII ion. When using the succinato dicarboxylate bridging ligand instead of acetate, compounds 2 and 3 were serendipitously formed, which have a closed structure with the succinate anion bridging two ZnDy subunits belonging to two different ligands. It should be noted that only compound 2 exhibits slow relaxation of magnetization in the absence of an external magnetic field. According to experimental and theoretical data, 2 relaxes through the second excited Kramers doublet (Ueff = 342 K). In contrast, 3 displays field-induced SMM behaviour (Ueff = 203 K). However, the Co/Zn diluted version of this compound 3Zn shows slow relaxation at zero field (Ueff = 347 K). Ab initio theoretical calculations clearly show that the weak ferromagnetic coupling between CoII and DyIII ions is at the origin of the lack of slow relaxation of this compound at zero field. Compound 2 and its diluted analogues 2Y and 3Zn show hysteresis loops at very low temperature, thus confirming their SMM behaviour. Finally, compounds 1 and 2 show DyIII based emission even at room temperature that, in the case of 2, allows us to extract the splitting of the ground 6H15/2 term, which matches reasonably well with theoretical calculations.

Crystal structures of five halido gold complexes involving piperidine or pyrrolidine as ligands or (protonated) as cations.

In bromido-(pyrrolidine-κN)gold(I) bis-(pyrrolidine-κN)gold(I) bromide, [AuBr(pyr)]·[Au(pyr)2]Br (pyr = pyrrolidine, C4H9N), 2, alternating [AuBr(pyr)] mol-ecules and [Au(pyr)2]+ cations are connected by aurophilic contacts to form infinite chains of residues parallel to the b axis. The chains are cross-linked by three N-H⋯Br- hydrogen bonds and an Au⋯Br contact to form a layer structure parallel to the ab plane. Tri-chlorido-(piperidine-κN)gold(III), [AuCl3(pip)] (pip = piperidine, C5H11N), 3, consists of mol-ecules with the expected square-planar coordination at the gold atom, which are connected by an N-H⋯Cl hydrogen bond and an Au⋯Cl contact to form a layer structure parallel to the ac plane. The structures of bis-(piperidinium) tetra-chlorido-aurate(III) chloride, (pipH)2[AuCl4]Cl, 4, and bis-(pyrrolidinium) tetra-bromido-aurate(III) bromide, (pyrH)2[AuBr4]Br, 6, are closely related but not isotypic. Compound 6 crystallizes in space group Ibam; the Au and two Br atoms of the anion lie in the mirror plane x, y, 0, whereas the bromide ions occupy special positions 0, 0.5, 0 and 0, 0.5, 0.25, with site symmetry 2/m. The NH2 group forms a hydrogen bond to one bromide ion, and also a three-centre hydrogen bond to the other bromide atom and to a metal-bonded Br atom. The packing involves chains of hydrogen-bonded pyrrolidinium and bromide ions parallel to the c axis, combined with a layer structure of [AuBr4]- and bromide anions, parallel to the ab plane and involving Au⋯Br and Br⋯Br contacts. Compound 4, however, crystallizes pseudosymmetrically in space group Iba2; two chlorine atoms of the anion lie on the twofold axis 0.5, 0.5, z, and there are two independent cations. The packing is closely similar to that of 6, but there are no N-H⋯Cl hydrogen bonds to metal-bonded chlorines. The contact distances Au⋯Cl are appreciably longer than their Au⋯Br counterparts in 6, whereas the Cl⋯Cl contact is much shorter than Br⋯Br in 6. Tri-bromido-(piperidine-κN)gold(III) crystallizes as its di-chloro-methane solvate, [AuBr3(pip)]·CH2Cl2, 7. It too displays a square-planar coordination at the gold atom. The packing involves hydrogen bonds N-H⋯Br, stacking of neighbouring AuBr3 units by Au⋯Br contacts, and a short Br⋯Br contact; these combine to form a layer structure parallel to the ac plane.

Direct blue 53, a biological dye, inhibits SARS-CoV-2 infection by blocking ACE2 and spike interaction in vitro and in vivo

COVID-19 is a global health problem caused by SARS-CoV-2, which has led to over 600 million infections and 6 million deaths. Developing novel antiviral drugs is of pivotal importance to slow down the epidemic swiftly. In this study, we identified five azo compounds as effective antiviral drugs to SARS-CoV-2, and mechanism study revealed their targets for impeding viral particles’ ability to bind to host receptors. Direct Blue 53, which displayed the strongest inhibitory impact, inhibited five mutant strains at micromole. In vitro, mechanism study demonstrated Direct Blue 53 inhibited viral infection through interaction with the spike of SARS-CoV-2. And 25 mg/kg/d compound treatment showed 50% or 60% survival protection against lethal Delta or Omicron BA.2 infection in vivo. Taken together, our results demonstrate that azo compounds with dimethyl-biphenyl-diyl-bis(azo)bis structure may be promising anti-SARS-CoV-2 drug candidates, which provide practicable therapies with the aid of structural optimizations and further research.

Role of ancillary ligands in selectivity towards acceptorless dehydrogenation versus dehydrogenative coupling of alcohols and amines catalyzed by cationic ruthenium(II)-CNC pincer complexes.

An unexpected reversal in catalytic activity for acceptorless dehydrogenative coupling compared to acceptorless alcohol dehydrogenation has been observed using a series of cationic Ru(II)-CNC pincer complexes with different ancillary ligands. In continuation of our study of cationic Ru(II)-CNC pincer complexes 1a-6a, new complexes with bulky N-wingtips [Ru(CNCiPr)(CO)(PPh3)Br]PF6 (1b), [Ru(CNCCy)(CO)(PPh3)Cl]PF6 (1c), [Ru(CNCCy)(CO)(PPh3)H]PF6 (2c), [Ru(CNCiPr)(PPh3)2Cl]PF6 (3b), [Ru(CNCCy)(PPh3)2Cl]PF6 (3c), [Ru(CNCiPr)(PPh3)2H]PF6 (4b), [Ru(CNCCy)(PPh3)2H]PF6 (4c), [Ru(CNCiPr)(DMSO)2Cl]PF6 (6b), and [Ru(CNCCy)(DMSO)2Cl]PF6 (6c) [CNCR = 2,6-bis(1-alkylimidazol-2-ylidene)-pyridine] have been synthesized and the catalytic activities of the new complexes have been compared with their N-methyl analogues for transfer hydrogenation of cyclohexanone and acceptorless dehydrogenation of benzyl alcohol. Furthermore, all complexes have been utilized as catalysts in the dehydrogenative coupling reaction of benzyl alcohol with amines. While the catalytic activities of the new complexes for transfer hydrogenation and acceptorless alcohol dehydrogenation were found to be in line with the previously observed trend based on the ancillary ligands (CO > COD > DMSO > PPh3), for the acceptorless dehydrogenative coupling reaction, complexes containing PPh3 and DMSO ligands performed better compared to complexes containing CO and COD ligands. Based on NMR and mass investigation of catalytic reactions, a plausible mechanism has been suggested to explain the difference in catalytic activity and its reversal during the dehydrogenative coupling reaction. Furthermore, the substrate scope for the dehydrogenative coupling reaction of benzyl alcohol with a wide range of amines has been explored, including synthesizing some pharmaceutically important imines. All new complexes have been characterized by various spectroscopic techniques, and the structures of 4b and 6b have been confirmed by the single-crystal X-ray diffraction technique.

Structural characterization of three hydride-bridged sodium aluminate compounds

The synthesis and single-crystal structures of three hydride-bridged sodium aluminate compounds containing the utility amide HMDS [N(SiMe3)2 or C6H18NSi2] are reported. Both bis[bis(trimethylsilyl)amido-2κN]-μ-hydrido-hydrido-2κH-(N,N,N′,N′′,N′′-pentamethyldiethylenetriamine-1κ3 N,N′,N′′)(tetrahydrofuran-1κO)aluminiumsodium, [AlNa(C6H18NSi2)2H2(C4H8O)(C9H23N3)] or (HMDS)2Al(H)2Na(THF)(PMDETA), (1) (THF = tetrahydrofuran, C4H8O; PMDETA = N,N,N′,N′′,N′′-pentamethyldiethylenetriamine, C9H23N3) and tetrakis[bis(trimethylsilyl)amido]-3κ2 N,4κ2 N-tetra-μ-hydrido-tetrakis(tetrahydrofuran)-1κ2 O,2κ2 O-dialuminiumdisodium, [Al2Na2(C6H18NSi2)4H4(C4H8O)4] or [(HMDS)2Al(H)2Na(THF)2]2 (2), are dihydrides. However, 1 is a dinuclear Al—H—Na monomer with one bridging and one terminal hydride ligand whilst in 2 all the hydride ligands bridge between Al and Na atoms to give a dimeric structure with a core (AlHNaH)2 eight-membered ring. In contrast, the structure of bis[bis(trimethylsilyl)amido]-3κN,4κN-dihydrido-3κH,4κH-tetra-μ-hydrido-bis(N,N,N′,N′′,N′′-pentamethyldiethylenetriamine)-1κ3 N,N′,N′′;2κ3 N,N′,N′′-dialuminiumdisodium, [Al2Na2(C6H18NSi2)2H6(C9H23N3)2] or [(HMDS)Al(H)3Na(PMDETA)]2 (3), also contains a (AlHNaH)2 eight-membered ring but is a trihydride with two bridging and one terminal hydride ligand per Al centre. The (AlHNaH)2 eight-membered rings of 2 and 3 differ in their structural details. That of 2 is based around a twofold axis and has a larger Al...Al intra-ring distance than that found in centrosymmetric 3.

Zn(II) halide coordination compounds with imidazole and 2-methylimidazole. Structural and computational characterization of intermolecular interactions and disorder

Novel zinc(II) coordination compounds with imidazole (Im) and 2-methylimidazole (2-MeIm) were prepared and characterized: [ZnX2(Im)2] (X = Cl (1a), Br (1b), I (1c)) and [ZnX2(2-MeIm)2] (X = Cl (2a), Br (2b), I (2c)). Coordination compounds 1a–c were prepared mechanochemically by neat grinding while 2a–c were prepared by solution synthesis. The complexes were characterized by FT-IR and NMR spectroscopy and by powder X-ray diffraction. Crystal and molecular structures were determined by the single crystal X-ray diffraction. The characteristic of all structures is a distorted tetrahedral coordination of zinc consisting of two halide atoms and two nitrogen atoms from the imidazole (or 2-methylimidazole) ligand. Molecules in 1a–c are interconnected by hydrogen bonds into 3D structures. Structures of 1b and 1c were found to have similar unit cells and similar crystal packing and hydrogen bonding. Introduction of the 2-methylimidazole substituent introduced disorder in the crystal structures of 2a–c. Because of the very small size of the crystals data were collected by synchrotron radiation. For the disordered 2a,2b and 2c fixed geometry was used in refining of the structures. Crystal structures of 2a–c are characterized by chains of molecules connected by hydrogen bonds of the type N–H⋅⋅⋅X, with weak π⋅⋅⋅π and van der Waals interactions between the chains. The QTAIM, RDG and NCI computational analysis of 1a and 2a–c confirmed the presence of weak attractive intermolecular interactions that can be attributed to weak N–H⋅⋅⋅X and van der Waals interactions.

Synthesis, Structural Characterization, Conformational and Topological Classification of Different Salts in the 2,2-Dimethylpropane-1,3-diamine/HCl/H2O-System

The reaction of 2,2-dimethylpropane-1,3-diamine (dmpn) with an excess of concentrated aqueous hydrochloric acid yielded colorless crystals of 2,2-dimethylpropane-1,3-diaminium dichloride, dmpnH2Cl2 (1), in addition to small amounts of a monohydrate, dmpnH2Cl2∙H2O (2). The compounds were studied via X-ray crystallography, IR and Raman spectroscopy, NMR spectroscopy and thermal analysis. Single crystal structure determinations on 1 and 2 showed that dmpnH2Cl2 exists in two polymorphic forms, 1a and 1b. The crystal structure of 1b showed to be much more complex than that of 1a. In the crystal structure of 2, four (dmpnH2)2+ cations and eight chloride anions form a cage constructed by N−H∙∙∙Cl hydrogen bonds. In the center of these cages water dimers with a O∙∙∙O distance of 2.776 (8) Å are present. In addition, a conformational analysis of the 2,2-dimethylpropane-1,3-diaminium cation was performed. The results are compared to the experimental findings of 1a, 1b, 2 and other related hydrogen bonded salt structures from the Cambridge crystallographic structure database (CCDC). Last, a topological classification of the solid-state structures of 1a and 2 was performed and the simplified topological networks are discussed.

Co(NCS)2(abpt)2 and Ni(NCS)2(abpt)2 [abpt is 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole]: structural characterization of polymorphs A and B.

The synthesis and structures of bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N2,N3]bis(thiocyanato-κN)cobalt(II), [Co(NCS)2(C12H10N6)2] or Co(NCS)2(abpt)2, and bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N2,N3]bis(thiocyanato-κN)nickel(II), [Ni(NCS)2(C12H10N6)2] or Ni(NCS)2(abpt)2, are reported. In both cases, two polymorphs, A and B, were identified and structurally characterized. For both polymorphs, the structures obtained with the different metals, i.e. CoII or NiII, were found to be isostructural. All of the structures contained an intramolecular N-H...N hydrogen bond, C-H...N interactions and π-π stacking interactions. No structural evidence was observed for a thermal spin crossover for either of the Co(NCS)2(abpt)2 polymorphs between 300 (2) and 120 (2) K.

The Structure of Bis(catecholato)silanes: Phase Adaptation by Dynamic Covalent Chemistry of the Si-O Bond.

Catechols occupy a unique role in the structural, bio-, and geochemistry of silicon. Although a wealth of knowledge exists on their hypercoordinate complexes, the structure of tetracoordinate bis(catecholato)silane, Si(catH)2 1, has been enigmatic since its first report in 1951. Indeed, the claim of a planar-tetracoordinated silicon in 1 triggered a prominent debate, which is unsettled to this day. Herewith, we present a comprehensive structural study on 1 and derivatives in the gas phase by electron diffraction, in a neon matrix by IR spectroscopy, in solution by diffusion NMR spectroscopy, and in the solid-state by X-ray diffraction and MAS NMR spectroscopy, complemented by high-level quantum-chemical computations. The compound exhibits unprecedented phase adaptation. In the gas phase, the monomeric bis(catecholato)silane is tetrahedral, but in the condensed phase, it is metastable toward oligomerization up to a degree controllable by the type of catechol, temperature, and concentration. For the first time, spectroscopic evidence is obtained for a rapid Si-O σ-bond metathesis reaction. Hence, this study sorts out a long-lasting debate and confirms dynamic covalent features for our Earth's crust's most abundant chemical bond.

Synthesis, characterization, X-ray crystal structure and antibacterial activity of bis[3-(4-chloro-N,N-diethylpyridine-2-carboxamide)] diselenide

An efficient methodology for the synthesis of bis[3-(4-chloro-N,N-diethylpyridine-2-carboxamide)] diselenide has been successfully achieved through ring lithiation using 2.2equivalents oflithium diisopropylamide (LDA) in THF. The hitherto unknown compound has been fully characterized by spectroscopic techniques NMR (1H and 13C), Mass spectrometry and elemental analysis. The crystal structure ofbis[3-(4-chloro-N,N-diethylpyridine-2-carboxamide)] diselenide has been determined by single crystal X-ray diffraction. The diselenide crystallizes in the monoclinic system (C2/c) with torsional angle of the selenium atoms attached to pyridyl rings (-C1–Se–Se–C1-) is −77.5(1). Bis[3-(4-chloro-N,N-diethylpyridine-2-carboxamide)] diselenide was found antibacterial active and results were compared with the most studied pyridylselenium compound (2,2′-dipyridyl diselenide) and standard drug Ampicillin.

STRUCTURE OF BIS(LIDOCAINE) TETRACHLORIDOCUPRATE(II)

The present paper reports on the synthesis and structure of bis(2-(diethylamino)-N-(2,6-dimethylphenyl)acetamide) or bis(lidocaine) tetrachloridocuprate(II). The complex with the formula (C14H23ON2)2CuCl4 (or (LidH)2[CuCl4]), crystallizes in the monoclinic space group P21/c with a = 15.7831(2), b = 24.2992(2), c = 17.8748(2) Å, β = 104.874(1)°,V = 6625.58(13) Å3, Z = 8, and Dc = 1.355 Mg/m3. The coordination of the Cu2+ ions with chlorine atoms generates two differently distorted tetrahedral anions [CuCl4]2–, while four protonated cations LidH+ remain in an outer coordination sphere. Anions and cations are associated by hydrogen bonds of the N–H···Cl type to form the 2((LidH)2[CuCl4]) dimer, in which the distance between two copper atoms is 8.95 Å. With the help of hydrogen bonds of the type N–H···O and N–H···Cl, each dimer is connected with four neighboring dimers, resulting in a three-dimensional structure in which dimers lie at an angle of 28.39° to the a crystallographic axis in the ab planes located at a distance of 10.67 Å from each other.

One pot synthesis of bis (dihydropyrimidinone) and tetrahydro-4H-chromenes derivatives using Ag2O/GO/TiO2 composite nanostructure

In this study, a simple and efficient synthesis reaction was used to prepare Bis (dihydropyrimidinone) derivatives through Biginelli condensation reaction of terephthalic aldehyde, 1,3-dicarbonyl compounds and (thio) urea or guanidine and tetrahydro-4H-chromenes via one pot condensation of aromatic aldehydes, malononitrile, and dimedone with Ag2O/GO/TiO2 composite nanostructures as the catalyst. The structural functionalities and morphological observations of catalyst were obtained using characterization techniques of field emission scanning electron microscopy, X-ray diffraction, Fourier transfer infrared (FT-IR) spectroscopy and transmission electron microscope. The structures of Bis (dihydropyrimidinone) and tetrahydro-4H-chromenes were confirmed by FT-IR, NMR, and mass spectroscopy. Excellent yields of products, simple reaction process and simple work-up are attractive features of these effective synthesis methods.

Synthesis and Structures of Bis(indolyl)-Coordinated Titanium Dichlorido Complexes and Their Catalytic Application in the Cyclotrimerization of Alkynes

Synthesis and Structures of Bis(indolyl)-Coordinated Titanium Dichlorido Complexes and Their Catalytic Application in the Cyclotrimerization of Alkynes

Aliphatic C–H hydroxylation activity and durability of a nickel complex catalyst according to the molecular structure of the bis(oxazoline) ligands

• Bis(oxazoline) complexes of nickel catalyze alkane hydroxylation with m-CPBA. • Structure of bis(oxazoline) ligands influences the catalytic performance. • Durability of catalysts toward O 2 depends on the structure of the bis(oxazoline) ligands. Applicability of the oxazoline-based compounds, bis(2-oxazolynyl)methane (BOX) and 2,6-bis(2-oxazolynyl)pyridine (PyBOX), as supporting ligands of nickel(II) complexes for the catalysis of aliphatic C H hydroxylation with m -CPBA ( meta -chloroperoxybenzoic acid) was explored. Substituent groups at the fourth and fifth positions of oxazoline rings and the bridgehead carbon atom of the BOX derivatives affected the catalytic performances toward cyclohexane hydroxylation. Presence of dioxygen led to a reduced catalytic performance of the nickel complexes, except in the case of a fully substituted BOX ligand complex.

SCREENING NATURAL PRODUCT COMPOUNDS FROM CLEISTOCALYX OPERCULATUS FOR PROTEIN TYROSINE PHOSPHATASE 1B INHIBITORY ACTIVITY BY USING MOLECULAR DOCKING METHOD

Background: Diabetes mellitus is a complex chronic disease. It is characterized by high level of glucose in the blood, caused by deficiency in insulin secretion from the β pancreatic’s cells or the operability of insulin. The protein tyrosine phosphatase 1B (PTP1B) catalyzes in order to remove of the phosphate group from the insulin receptor's phosphotyrosine, so it reduces the effects of insulin on target tissues. Therefore, inhibiting this enzyme is an effective method to treat diabetes mellitus. Cleistocalyx operculatus has been shown to be effective with the treatment of diabetes mellitus. Objectives: In this study, we evaluated the inhibitory effects of PTP1B enzyme of Cleistocalyx operculatus’s compounds by using molecular docking method. Materials and Methods: The protein tyrosin protease 1B structure was obtained from Protein Data Bank. Compounds were collected from the publication of Cleistocalyx operculatus and these structures were obtained from the PubChem database. Molecular docking was done by Autodock vina software. Lipinski Rule of Five is used to compare compounds with drug-like and non-drug-like properties. Pharmacokinetic parameters of potential compounds were evaluated using the pkCSM tool. Results: Based on previous publication of Cleistocalyx operculatus, we have collected 62 compounds. The results showed that there are 4 compounds have PTP1B inhibitory effect stronger than the positive control including abieta-7,13-diene, kaempferol, quercetin, luteolin. Analysising Lipinski rule of five showed that all 4 compounds have drug-likeness propieties. Moreover, predict ADMET showed that these compounds have good intestinal absorption and low toxicity. Conclusion: Therefore, kaempferol, quercetin, luteolin and abieta-7,13-diene may be potential natural product compound for diatetes treatment.

Synthesis and antioxidant properties of bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propyl)phosphite

Bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propyl)phosphite was synthesized by reaction of 2,6-di-tert-butyl-4-(3-hydroxyproyl)phenol with dibutyl phosphite. The structure of bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propyl)phosphite was supported by IR and NMR (1H, 13C, 31P) spectroscopy; its composition was confirmed by elemental analysis. High antioxidant activity of the synthesized phosphite has been shown in a model reaction with the free chromogen-radical 2,2-diphenyl-1-picrylhydrazyl and under conditions of accelerated thermal oxidation of paraffinic and mineral oils.

Экспериментальное и теоретическое исследование спектроскопии биядерных борфторидных комплексов дипиррометенов

The spectroscopic characteristics of mono and binuclear boron fluoride complexes of dipyrromethenes in various solvents and solid-state polymer media (films) are investigated depending on the wavelength and intensity of the exciting radiation. Along with experimental studies, quantum-chemical calculations of the electronic structure and geometry of electronically excited molecules were carried out, an interpretation of the experimental data (absorption and emission bands) was given, and a connection between the absorption spectra and the structure of bis (dipyrromethenes) and their conformations was established. The analysis of the obtained results is carried out in comparison with the modern literature data. The possibilities of practical application of the studied compounds in the development of liquid and solid-state lasers and optical solvent polarity sensor are discussed.

One-pot synthesis of cobalt complexes with 2,6-bis(arylimino)phenoxyl/phenthioxyl ligands and catalysis on isoprene polymerization.

Several cobalt complexes supported by 2,6-bis(arylimino)phenoxyl/phenthioxyl ligands κ2N,X-Ar[NXN]CoCl(THF) (1a, X = O, Ar = 2,6-Me2C6H3; 1b, X = O, Ar = 2,6-iPr2C6H3; 2a, X = S, Ar = 2,6-Me2C6H3; 2b, X = S, Ar = 2,6-iPr2C6H3) were synthesized by direct oxygen(sulfur) insertion into the C-Co bond of the mixed-valence cobalt complexes {κ2C,N,η6-Ar[NCN]Co-κN-CoCl(μ-Cl)}2. Crystallization of 1b in the presence of water gave the hydrolysis product 1b'. Treatment of Ar[NCN]Li with dioxygen followed by the addition of CoCl2 afforded the heteroatomic complexes {κ2N,O-Ar[NON]Co(μ-Cl)2Li}2 (3a, Ar = 2,6-Me2C6H3; 3b, Ar = 2,6-iPr2C6H3) or κ2N,O-Ar[NON]Co2Cl2(μ-Cl)2Li(THF)2 (4a, Ar = 2,6-Me2C6H3; 4b, Ar = 2,6-iPr2C6H3) depending on the amount of CoCl2 used. The Co(iii)/Li heterometallic complex 3b' with imino-phenoxyl-amino ligands was formed probably via a redox reaction of 3b. The reactions of Ar[NCN]Li with elemental sulfur and CoCl2 gave κ2N,S-Ar[NSN]Co2Cl2(μ-Cl)2Li(THF)2 (5a, Ar = 2,6-Me2C6H3; 5b, Ar = 2,6-iPr2C6H3) respectively. These complexes were well characterized by FT-IR and elemental analyses, and the molecular structures of 1b', 3b', 4a, and 4b were confirmed by X-ray crystallography. Upon activation with Al2Et3Cl3 in toluene, these complexes showed high activities in isoprene polymerization affording cis-1,4 enriched polymers with a moderate molecular weight (0.85-4.72 × 104 Da).