Synthesis,spectroscopic characterization,crystal structure and theoretical investigation of two azo-palladium (II) complexes derived from substituted (1-phenylazo)-2-naphtol

Transition Metal Chemistry - The ortho-substituted (E)-1-((2-methoxyphenyl)diazenyl)naphthalen-2-ol and the meta-substituted (E)-1-((3-methoxyphenyl)diazenyl)naphthalen-2-ol were, respectively,...     

Synthesis of deuterium-labeled derivatives of dimethylallyl diphosphate

Short practical syntheses for five deuterium-labeled derivatives of dimethylallyl diphosphate (DMAPP) useful for enzymological studies are reported. These include the preparation of the C1-labeled derivatives (R)-[1-2H]3-methylbut-2-enyl diphosphate ((R)-[1-2H]1-OPP) and (S)-[1-2H]3-methylbut-2-enyl diphosphate ((S)-[1-2H]1-OPP), the C2-labeled derivative [2-2H]3-methylbut-2-enyl diphosphate ([2-2H]1-OPP), and the methyl-labeled derivatives (E)-[4,4,4-2H3]3-methylbut-2-enyl diphosphate ((E)-[4,4,4-2H3]1-OPP) and (Z)-[4,4,4-2H3]3-methyl-but-2-enyl diphosphate ((Z)-[4,4,4-2H3]1-OPP).     

Multi-carbazole derivatives for two-photon absorption data storage:Synthesis,optical properties and theoretical calculation

Two novel quadrupolar organic compounds, 3-(4-((E)-2-(9-butyl-9H-carbazol-6-yl) vinyl)styryl)-9-propyl-9H-carbazole (BCSPC) and 3-(3-(3-((1E)-2-(4-((E)-2-(3-(3,5-bis(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazol-6-yl)vinyl)phenyl) vinyl)-9-butyl-9H-carbazol-6-yl)-5-(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazole (BCPBC), with different conjugated arms, have been designed and synthesized. Their one-and two-photon absorption (TPA) and excited fluorescence properties have been experimentally inve...     

Synthesis,characterization and biological properties of novel ON donor bidentate Schiff bases and their copper(II) complexes

Four novel ON donor Schiff bases (E)-3-((4-phenoxyphenylimino)methyl)benzene-1,2-diol (HL₁),(E)-3-((4-(4-biphenyloxy)phenyliminomethyl)benzene-1,2-diol (HL₂), (E)-3-((4-naphthoxyphenylimino)methyl)benzene-1,2-diol (HL₃), (E)-3-((4-(2-naphthoxy)phenylimino)methyl)benzene-1,2-diol (HL₄) and their copper(II) complexes bis((E)-3-((4-phenoxyphenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L₁)₂) bis((E)-3-((4-(4-biphenyloxy)phenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L₂)₂), bis((E)-3-((4-naphthoxyphenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L₃)₂), bis((E)-3-((4-(2-naphthoxy)phenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L₄)₂) have been synthesized and characterized by spectroscopic (FTIR, NMR, UV–visible) and elemental analysis. The crystal structures of HL₁, HL₂, HL_3, and HL₄ have been determined, which reveal intramolecular N-H?O (HL₁, HL₂, HL_3, and HL₄) hydrogen bonds in the solid state. Keto-amine and enol-imine tautomerism is exhibited by the Schiff bases in solid and solution states. The Schiff bases and their copper(II) complexes have been screened for their biological activities. In antimicrobial assays (antibacterial and antifungal), HL₄ showed promising results against all strains through dual inhibition property while the rest of the compounds showed activity against selective strains. On the other hand, in cytotoxic, DPPH, and inhibition of hydroxyl (OH) free radical-induced DNA damage assays, the results were found significantly correlated with each other, i.e. the ligands HL₁ and HL₂ showed moderate activity while their complexes Cu(L₁)₂ and Cu(L₂)₂ exhibited prominent increase in activity. As the results of these assays are supporting each other, it represents the strong positive correlation and antioxidant nature of investigated compounds.     

Optimization,Spectroscopic(FT-IR,Excited States,UV/Vis) Studies,FMO, ELF,LOL, QTAIM and NBO Analyses and Electronic Properties of Two New Pyrimidine Derivatives

In the given research, the molecular structures of two new compounds, 4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-amine(PM-1) and N-(4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-yl)-4,6-dichloro 1,3,5-1,3,5-triazin-2-amine(PM-2), have been studied with the use of density functional theory(DFT/B3 LYP/MidiX) in dimethylformamide(DMF) for the first time. The electronic spectra of the new compounds in a DMF solvent were carried out by temporally dependent density functional theory(TD-DFT) method. The computed absorption spectral data of the title compounds are in good agreement with the experimental data, thus allowing an assignment of the UV/Vis spectra. The equilibrium geometry, the HOMO and LUMO molecular orbitals, excitation energies, oscillator strengths and Natural Bond Orbital(NBO) analysis for the molecules have also been calculated and presented. FT-IR spectra of the title molecules are recorded and discussed. The electron location function(ELF), localized orbital locator(LOL) and quantum theory of atoms in molecules(QTAIM) analyses were also carried out. On the basis of polyvinyl alcohol(PVA) and synthesized molecules, polarizer for UV/Vis region of the spectrum has been developed.     

Three new diterpenes and the biological activity of different extracts of Jasonia montana

Three new diterpenes, namely jasonin-a (1), jasonin-b (2), and jasonin-c (3) were isolated from the aerial parts of Jasonia montana (Asteraceae). Their structures were elucidated on the basis of spectral data as [(1E)-2-((2S)-1,2,5-trimethylbicyclo[3.2.l]octan-8-yl)vinyl] benzene-3-carboxylic acid (1), [3-((2S, 5S)-1,2, 5-trimethylcycloheptanyl)propyl]benzene-3-carboxylic acid (2), and [(1E)-3-((7R)-1,7-dimethy-4-methylenecycloheptanyl)prop-1-enyl] benzene-3-carboxylic acid (3). In addition, the previously reported 5,7,3'-trihydroxy-3,6,4'-trimethoxy flavone designated as centaureidin (4), was also isolated and characterized from this source. The different extracts of the plant were also screened for hypoglycemic, antidiabetic, and antimicrobial activities, wherein the petroleum ether and ethanolic extracts exhibited hypoglycemic and antidiabetic activity, and the petroleum ether and chloroform extracts showed antimicrobial activity.     

A new Schiff base system bearing two naphthalene groups as fluorescent chemodosimeter for Zn2+ ion and its logic gate behavior

1-((E)-(2-((2-nitrobenzyl)(2-((E)-(2-hydroxynaphthalen-1-yl)methyleneamino)ethyl)amino)ethylimino)methyl)naphthalen-2-ol (H(2)L), The new compound featuring two naphthalene units was synthesized and characterized. We find that H(2)L has high selectivity and sensitivity to detect Zn(2+) ion over other metal ions such as Na(+), Ag(+), Cd(2+), Co(2+), Cr(3+), Cu(2+), Hg(2+), Mn(2+), Ni(2+), Fe(3+), and the sensitivity is about 10(-7)M. The fluorescent changes of H(2)L upon the addition of cations Zn(2+) and triethylamine is utilized as an AND logic gate at the molecular level, using Zn(2+) and triethylamine as chemical inputs and the fluorescence intensity signal as output.     

DNA binding,cleavage, catalytic,magnetic active; 2,2–bipyridyl based d-f hetero binuclear Gd(III), Cu(II) complexes and their Electrochemical,fluorescence studies

Several 2,2-bipyridyl-based d-f heterobinuclear [GdCuL1-5(bpy)2(NO3)2] complexes are present, where (Ligand 1) (9E)-N¹-(2-Hydroxy-5-methylbenzylidene)–N²-((E)-2-(2-hydroxy-5-methyl benzylideneamino)ethyl)ethane-1,2-diamine. (Ligand 2) N¹,N¹-bis((E)-2-(2-hydroxy-5-methylbenzylideneamino)ethyl)ethane-1,2-diamine. (Ligand 3) (9E)-N¹-(2-((E)-2-(2-hydroxy-5-methylbenzylideneamino)ethylamino)ethyl)–N²-(2-hydroxy-5-methylbenzylidene)ethane-1,2-diamine. (Ligand 4) (9E)-N¹-(2-((E)-3-(2-hydroxy-5- methylbenzylideneamino) propylamino) ethyl)–N³-(2-hydroxy-5-methylbenzylidene)propane-1,3-diamine and (Ligand 5) (9E)-N-(2-hydroxy-5-methylbenzylidene)-3-(4-((E)-3-(2-hydroxy-5-methylbenzylideneamino)propyl)piperazin-1-yl)propan-1-amine. These compounds were described using spectroscopy and the elemental analysis method. Researches were conducted into the luminous, Genetic code, catalytic, magnetism, and breaking attributes of the [GdCuL1-5(bpy)2(NO3)2] complexes. In DMF with 0.1 M tetra-n-butylammonium perchlorate, the binuclear [GdCuL1-5(bpy)2(NO3)2] network complexes exhibit two one electron irreversible reduction events. VSM was used to calculate the complexes' magnetic susceptibility. There is ferromagnetic coupling in the [GdCuL1-5(bpy)2(NO3)2] complexes. The [GdCuL1-5(bpy)2(NO3)2] complexes' excited state lifetimes lengthen in the following order: [GdCuL5(bpy)₂] [GdCuL1(bpy)2(NO3)2] [GdCuL3(bpy)2(NO3)2] [GdCuL4(bpy)2] and [GdCuL2(bpy)2(NO3)2]. The binuclear [GdCuL1-5(bpy)2(NO3)2] complexes' inceptive rate of progress for oxidizing 1,2-benzenediol to cyclohexa-3,5-diene-1,2-dione are longer chains with higher activity. Both the [GdCuL5(bpy)2(NO3)2] and [GdCuL4(bpy)2(NO3)2] complexes have strong DNA genetic code properties in the calf genus thymus. The complexes exhibit considerable singlet oxygen-mediated oxidative rift of circular recombinant plasmid pBR322 cloning vector in the existence of 2-sulfanylethanol.     

Preparation of 2-, 3-, 4- and 7-(2-alkylcarbamoyl-1-alkylvinyl)benzo[b]furans and their BLT1 and/or BLT2 inhibitory activities

Several 2-alkylcarbamoyl-1-alkylvinylbenzo[b]furans were designed to find a selective leukotriene B4 (LTB4) receptor antagonist. 2-(2-Alkylcarbamoyl-1-alkylvinyl)benzo[b]furans having a substituent group at the 3-position, 4-(2-alkylcarbamoyl-1-methylvinyl)benzo[b]furans having a substituent group at the 3-position, and 7-(2-alkylcarbamoyl-1-methylvinyl)benzo[b]furans and 3-(2-alkylcarbamoyl-1-alkylvinyl)benzo[b]furans were prepared and evaluated for LTB4 receptor (BLT1 and BLT2) inhibitory activities. (E)-3-Amino-4-[2-[2-(3,4-dimethoxyphenyl)ethylcarbamoyl]-1-methylvinyl]benzo[b]furan ((E)-17c) showed potent and selective inhibitory activity for BLT2. On the other hand, (E)-7-(2-diethylcarbamoyl-1-methylvinyl)benzo[b]furan ((E)-27a) showed potent inhibitory activity for both BLT1 and BLT2.     

New synthesized ligands for detection of heavy metal ions

Some new chemo-sensors (4,4'-((1E,1′E)-(2,2′-dichloro-[1,1′-biphenyl]-4,4′-diyl)bis(diazene-2,1-diyl))bis(3,5-dihydroxybenzoic acid), 4-((E)-(4-(N-(4-((E)-(4-carboxy-2,6-dihydroxyphenyl)diazenyl)phenyl)sulfamoyl)phenyl)diazenyl)-3,5-dihydroxybenzoic acid, 4-((E)-(4-((4-((E)-(4-carboxy-2,6-dihydroxyphenyl)diazenyl)-2-sulfophenyl)amino)phenyl)diazenyl)-3,5-dihydroxybenzoic acid) were synthesized. These synthesized sensors were then characterized by FTIR, TLC, UV–Visible spectrophotometry, and NMR techniques. The sensors showed the best results for detection of all type of heavy metal ions simply by changing the colour of metal ion solution and by shifting in the λ_max values of sensors due to interactions.     

Density functional theory for investigation of optical and spectroscopic properties of zinc-quinonoid complexes as semiconductor materials

Structural Chemistry - Three Zn(II) complexes of a new organic compound [(E)-4-methyl-N1-((E)-4-methyl-6-(p-tolylimino) cyclohex-3-en-1-ylidene)-N2-(p-tolyl) benzene-1, 2-diamine] (HMBD) were...     

A catalytic asymmetric synthesis of chiral glycidic acid derivatives through chiral dioxirane-mediated catalytic asymmetric epoxidation of cinnamic acid derivatives

A novel and practical asymmetric synthesis of chiral glycidic acid derivatives involving methyl (2R,3S)-3-(4-methoxyphenyl)glycidate ((2R,3S)-2a), a key intermediate for diltiazem hydrochloride (1), was developed. Treatment of methyl (E)-4-methoxycinnamate ((E)-3a) with chiral dioxirane, generated in situ from a catalytic amount (5 mol %) of an 11-membered C(2)-symmetric binaphthyl ketone (R)-7a, provided (2R,3S)-2a in 92% yield and 80% ee. Other cinnamic acid esters and amides were epoxidized by the use of the same procedure to give the corresponding chiral glycidic acid derivatives with up to 95% yield and 92% ee. Higher enantioselectivities in the asymmetric epoxidation of (E)-cinnamates than that of (E)-stilbene derivatives were observed and were proposed to be attributed to a dipole-dipole repulsion between oxygen atoms of an ester group in the cinnamates and those of the lactone moieties in the binaphthyl dioxirane.     

Quantum yields for product formation in the 120-133 nm photodissociation of O2

The photodissociation of O(2) in the region from 120-133 nm has been investigated using product imaging. The spectrum in this region is dominated by transitions from the ground state to the first three vibrational levels of the E (3)Sigma(u) (-) state. The O((1)D)+O((3)P) channel is the only product channel observed by product imaging for dissociation at either 124.4 nm or 120.4 nm. The O((1)D(2)) product is aligned in the molecular frame in such a way that its J vector is perpendicular to the relative velocity vector between the O((1)D) and the O((3)P). The variation in the anisotropy of dissociation is approximately predicted by considering transitions on individual lines and then taking into account the coherent excitation of overlapping resonances. At 132.7 nm, both the O((1)D)+O((3)P) and the O((3)P)+O((3)P) channels are observed with branching ratios of 0.40+/-0.08 and 0.60+/-0.09, respectively. At 130.2 nm, the quantum yield for production of O((1)D) is 0.76+/-0.28.     

Novel synthesis of conjugated dienes attached to a quaternary carbon center via Pd(0)-catalyzed deconjugative allylation of alkenylidenemalonates

Palladium(0)-catalyzed deconjugative allylation of alkenylidenemalonates and alkylidenemalonates was achieved for the first time. Reactions of dimethyl 2-((E)-but-2-enylidene)malonate with various allylic acetates using LHMDS as a base in DMF in the presence of Pd(2)dba(3) (2.5 mol %) and PPh(3) (10 mol %) proceeded at room temperature to give the corresponding alpha-allylation products in good yields in a regio- and stereoselective manner. This reaction can also be used for allylation of dimethyl ethylidenemalonate or dimethyl 2-((E)-pent-2-enylidene)malonate and give the desired alpha-allylation products in good yields.     

Preparation of 2- and 4-(2-alkylcarbamoyl-1-methylvinyl)-7-alkyloxybenzo[b]furans having potent antagonistic activity against human leukotriene B4 BLT1 and/or BLT2 receptors

(E)-2-Acetyl-4-(2-diethylcarbamoyl-1-methylvinyl)-7-(1-phenylethoxy)benzo[b]furan (4b) with a characteristic conformation and (E)-2-(2-morpholinocarbo-1-methylvinyl)-7-ethoxycarbopropoxybenzo[b]furan ((E)-3b) were prepared and evaluated for their leukotriene B4(LTB4) antagonistic activity. Compound 4b showed potent antagonistic activity against human BLT1 and BLT2 receptors. Compound (E)-3b displayed selective BLT2 receptor antagonistic activity. Both compounds were inactive to cysteinyl LT receptors.     

Side-hole to anti-hole conversion in time-resolved transient spectral hole-burning of emerald: ground state level versus excited state population storage in low magnetic fields

Time-resolved transient spectral hole-burning experiments in zero field and in low magnetic fields B( parallelc) are reported for the chromium(III) R(1)-line, 2A((2)E)<-- 2A((4)A(2)) of Chatham lab created emerald, Be(3)Al(2)Si(6)O(18)ratio Cr(III)(0.0017% per weight), in the temperature range of 3 to 12 K. In low magnetic fields and temperatures >5 K conversion of side-holes to anti-holes is observed with progressing time. Anti-holes are due to the population stored in ground state levels. The dynamics of the hole pattern can be well modelled by a set of coupled differential equations for the levels of the (4)A(2) and (2)E multiplets. The measurements allow the simultaneous determination of g-factors and spin-lattice relaxation rates in the excited state and the ground state. At 6 K the relaxation times between the split +/-1/2 2A((2)E) excited state levels and +/-3/2 2A((4)A(2)) levels of the ground state are about 0.16 ms and 9 ms, respectively. From the temperature dependence it follows that the spin-lattice relaxation rates are dominated by Orbach processes in the experimental temperature range.     

Analysis of M···H-Si interactions in [{M(CpSiMe2H)Cl3}2], (M = Zr, Hf, Ti and Mo) complexes

For the d(0) complex [{Zr(CpSiMe(2)H)Cl(3)}(2)] which contains a linear Si-H···Zr interaction across the dimer, DFT calculations are in good agreement with X-ray structures. The BP86 functional shows a slightly stronger interaction than B3LYP but for qualitative purposes either functional is sufficient. QTAIM analysis shows a bond critical point (bcp) for the interaction, a small negative value for the total energy density [H((r))] and the H atomic basin decreases in energy, E(H), and atomic volume compared to the free ligand. NBO analysis showed E(2) for Si-H σ to Zr(dz(2)) donation at 42.8 kcal mol(-1) and a 34% spatial overlap for the interaction consistent with an inverse hydrogen bond. The Wiberg bond index for the interaction is 0.1735 (0.7205 for the Si-H bond), ν((Si-H)) and (1)J((Si-H)) at 2060 cm(-1) and 145.4 Hz compared to 2183 cm(-1) and 172.1 Hz in the free ligand. Using a "synthesis by computation" approach to forming like complexes, similar features were found for [{Hf(CpSiMe(2)H)Cl(3)}(2)]. The titanium complex [{Ti(CpSiMe(2)H)Cl(3)}(2)] does not contain any Si-H···Ti interaction as rotation about the C-Si bond of the ligand occurs to place the Si-H bond hydrogen closer to a terminal chloro ligand across the dimer. An increase in electron density on the metal in the d(2) complex [{Mo(CpSiMe(2)H)Cl(3)}(2)] results in a stronger interaction with a distinct QTAIM analysis bcp [ρ((r)) 0.0448 a.u.], a small negative value for H((r)) and a much reduced H atomic volume. NBO analysis shows E(2) for Si-H σ to Mo(dz(2)) donation at 143.1 kcal mol(-1) and a 29% spatial overlap. Mo(dz(2)) to Si-H σ* donation (back donation) is minimal [E(2) 1.3 kcal mol(-1), ~1% spatial overlap]. The Wiberg bond index is 0.3114 (0.5667 for the Si-H bond), ν((Si-H)) 2015 cm(-1) and (1)J((Si-H)) 120.6 Hz.     

A biomimetic sensor based on specific receptor ETBD and Fe3O4@Au/MoS2/GN for signal enhancement shows highly selective electrochemical response to ultra-trace lead (II)

Journal of Solid State Electrochemistry - A lead-chelating ligand, 2,2′-((1E)-((4-((2-mercaptoethyl)thio)-1,2phenylene)bis(azany-lylidene))bis(methanylylide-ne))diphenol (ETBD), was...     

Synthesis and coordination behavior of planar-chiral ferrocene alkenylphosphines

A series of planar-chiral ferrocene alkenylphosphines, (S(p))-2-(diphenylphosphino)-1-vinylferrocene (2), (S(p))-2-(diphenylphosphino)-1-(prop-1-en-1-yl)ferrocene (3; as a mixture of Z and E isomers in ca. 5:1 ratio), and (E,S(p))-2-(diphenylphosphino)-1-(2-phenylethen-1-yl)ferrocene ((E)-4), was obtained by Wittig and Horner-Wadsworth-Emmons reactions from the common precursor, (S(p))-2-(diphenylphosphino)ferrocene-1-carboxaldehyde (1). Coordination properties of these novel ferrocene donors were studied in their palladium(II) and tungsten(0)-carbonyl complexes. The reaction between 2 and [{Pd(mu-Cl)(L(NC))}2] (5, L(NC) = 2-{(dimethylamino)methyl-kappaN}phenyl-kappaC(1)) gave the bridge-cleavage product [PdCl(L(NC))(2-kappaP)] (6) while the reaction with [Pd(L(NC))(MeCN)2]ClO4 (7) yielded the cationic bis(chelate) [Pd(L(NC))(2-eta2:kappaP)]ClO4 (8). Chelate complexes of the type [W(CO)4(L-eta2:kappaP)] (9 with L = 2; (Z/E)-10 with L = (Z/E)-3) were obtained by reacting [W(CO)4(cod)] (cod = eta2:eta2-cycloocta-1,5-diene) with the appropriate phosphinoalkene in refluxing toluene while a similar reaction with (E)-4 yielded mixtures of [W(CO)5(4-kappaP)] ((E)-11) and [W(CO)4(4-eta2:kappaP)] ((E)-12). All compounds were characterized by spectral methods (multinuclear NMR, IR, MS, and CD), and the structures of 1, 2, 8, 9, (Z/E)-10, and (E)-11 were corroborated by X-ray diffraction analysis. Ligands 2 and (E)-4 as well as their complexes 6, 8, 9, (E)-11, and (E)-12 were further studied by electrochemical methods.