Fast Atom Bombardment Mass Spectrometry Research Articles

LC/MS Analysis of Cyclo Fatty Acid-containing Triacylglycerols in Cottonseed Oil

We measured the constituent triacylglycerol of cotton oil, the only edible oil containing a cyclo fatty acid. Due to the difficulty of obtaining a standard for triacylglycerols containing cyclo fatty acids, cotton oil is analyzed using cyclo triacylglycerol in kapok oil as a reference. Analytical methods used liquid chromatography fast atom bombardment mass spectrometry (LC / FAB-MS) using a matrix of 3% m-NBA containing 3 mM NaCl, and orthogonal transfer method for APCI / TOF-MS. FAB mass spectral properties of triacylglycerols containing cyclo fatty acids can be observed with [M + Na]+, [M-1]+ molecular ions, and [M- (RCOO)] + fragments. In the orthogonal APCI / TOF-MS spectrum, only the [M-1] + molecular ion appears, so that the presence of triacylglycerol containing CPFA becomes apparent. On the other hand, chain triacylglycerol can be observed as [M + 1]+ molecular ions and [M- (RCOO)]+ fragments. Based on these observations, triacylglycerols containing ten types of cyclo fatty acids were successfully successfully detected in crude cottonseed oil. In addition, the APCI/TOF-MS technique successfully detected dilinoleoyl-marvalyl-glycerol and palmtoyl-linoleoyl-marvalyl glycerol in the purified cottonseed oil.

Crystal structures of the first diselenophosphinate molybdenum(II) allyl complexes: [Mo(CH3CN)(κ3-C3H5)](CO)2(κ2-Se2PPh2)] and [Mo(κ3-C3H5)(CO)2(κ2-Phen)(κ1-Se2PPh2)

A reaction of [Mo(CH3CN)2(κ3-C3H5)(CO)2(Br)] (complex 1) and (Et4N)[Se2PPh2] (complex 2) produces a κ2-diselenophosphinate molybdenum [Mo(CH3CN)(κ3-C3H5)(CO)2(κ2-Se2PPh2)] complex (complex 3). Treatment of 3 with 1,10-phenanthroline, C12H8N2, yields a κ1-diseleno­phosphinate [Mo(κ3-C3H5)(CO)2(κ2-Phen)(κ1-Se2PPh2)] complex (complex 4). The coordination geometry around the molybdenum atom of complexes 3 and 4 is octahedral with aceto­nitrile, allyl, two carbonyls, and two selenium atoms and allyl, two carbonyls, two nitrogen atoms of the 1,10-phenanthroline ligand, and one selenium atom, occupying six-coordination sites, respectively. To the best of our knowledge, complexes 3 and 4 are the first diselenophosphinate molybdenum allyl complexes. Complexes 3 and 4 are characterized through the elemental analysis, fast atom bombardment mass spectrometry, 31P NMR spectroscopy, and single crystal X-ray diffraction.

A Review on Microbial Surfactants: Production, Classifications, Properties and Characterization

Surfactants are a surface-active group of molecular compounds with hydrophobic and hydrophilic moieties in one single molecule that distributes themselves between two immiscible fluids, reduce surface/ interfacial tensions and cause the solubility of non-polar compounds in polar solvents. Besides surface and interfacial activities, they display properties such as solubilization, detergency, lubrication, emulsification, stabilization and foaming capacity. Microbiologically derived surfactants are called biosurfactants. They are produced as either metabolic products or as the surface chemistry of an actual cell. The employment of screening techniques such as surface tension measurements, drop collapse test, oil spreading assay, emulsification index (%EI24), cetyltrimethylammonium bromide (CTAB)/methylene blue agar plate test and strain characterization. Others are analytical techniques including liquid chromatography-mass spectroscopy, thin layer chromatography, high-performance liquid chromatography, Fourier transform infrared spectroscopy, nuclear magnetic resonance, fast atom bombardment-mass spectrometry and electrospray ionization-mass spectrometry. These have led to the identification of biosurfactant producing microorganisms, properties and characterization of biosurfactants. Therefore, this review tends to provide the current knowledge of the screening techniques and chromatography/spectroscopic tools employed to study biosurfactants. Results from a detailed study of these tools can unveil new surfactant producing microorganism, decipher chemical diversity and multifunctional properties of biosurfactants critical for applications in diverse industrial sectors.

Cordidepsine is A Potential New Anti-HIV Depsidone from Cordia millenii, Baker.

Chemical investigation of Cordia millenii, Baker resulted in the isolation of a new depsidone, cordidepsine (1), along with twelve known compounds including cyclooctasulfur (2), lup-20(29)-en-3-triacontanoate (3), 1-(26-hydroxyhexacosanoyl)glycerol (4), glyceryl-1-hexacosanoate (5) betulinic acid (6), lupenone (7), β-amyrone (8), lupeol (9), β-amyrin (10), allantoin (11), 2′-(4-hydroxyphenyl)ethylpropanoate (12) and stigmasterol glycoside (13). Hemi-synthetic reactions were carried out on two isolated compounds (5 and 6) to afford two new derivatives, that is, cordicerol A (14) and cordicerol B (15), respectively. The chemical structures of all the compounds were established based on analysis and interpretation of spectroscopic data such as electron ionization mass spectrometry (EI–MS), high resolution electrospray ionization mass spectrometry (HR-ESI–MS), fast atom bombardment mass spectrometry (FAB–MS), one dimension and two dimension nuclear magnetic resonance (1D and 2D-NMR) spectral data as well as X-ray crystallography (XRC). Lupeol ester derivatives [Lup-20(29)-en-3-triacontanoate (3)], monoglycerol derivatives [1-(26-hydroxyhexacosanoyl)glycerol (4) and glyceryl-1 hexacosanoate (5)] were isolated for the first time from Cordia genus while sulfur allotrope [cyclooctasulfur (2)] was isolated for the first time from plant origin. Biological assays cordidepsine (1) exhibited significant anti-HIV integrase activity with IC50 = 4.65 μM; EtOAc extract of stem barks, EtOAc fraction of roots and leaves were not toxic against 3T3 cells.

The present state of studies on attractive and amphiphilic multi-functional methylated β-cyclodextrins and their purity measurements

β-Cyclodextrins (β-CD) are widely used in multiple fields such as medicine, agriculture, alimentation, and cosmetics because their hydrophobic cavity enables the formation of inclusion complexes with various organic compounds to improve their performances. There are three types of methylated β-CDs (M-β-CDs) on the market, prepared by the introduction of methyl groups on various sites: 2,3,6-tri-O-methyl-β-CD (TM-β-CD), 2,6-di-O-methyl-β-CD (DM-β-CD), and randomly methyl-β-CD (RM-β-CD). M-β-CDs are now used in medical as well as non-medical systems due to their significant water solubility compared to β-CD and unique amphiphilic property in water and organic solvents despite the possibility of tissue damage from nephrotoxicity. It is important to investigate the degree of substitution of M-β-CDs by methyl groups for further applications in a wide range of fields. Studies investigating the substitution degree of M-β-CDs have been carried out for many years. The aim of this study is to analyze the tendency of substitution number of methyl group in RM-β-CD, as a simpler analysis method. First, we analyzed RM-β-CD with simple methods such as hydrophilic interaction chromatography (HILIC) using a refractive index detector (RID) that is widely used for the high performance liquid chromatography (HPLC) analysis of sugars. After separation, liquid chromatography/electrospray ionization mass spectrometry and fast atom bombardment mass spectrometry measurements were carried out on each fraction. In addition, TM-β-CD and DM-β-CD were also analyzed by reverse phase-HPLC with ODS column.

New Diterpenes with a Fused 6-5-6-6 Ring System Isolated from the Marine Sponge-Derived Fungus Trichoderma harzianum.

New diterpenes, namely, trichodermanins F–H, with a fused 6-5-6-6 ring system were isolated from the fungus Trichoderma harzianum OUPS-111D-4 separated from a marine sponge Halichondria okadai. These chemical structures were elucidated by 1D and 2D NMR as well as high-resolution fast atom bombardment mass spectrometry (HRFABMS) spectral analyses. We established their absolute stereostructures by application of the modified Mosher’s method or circular dichroism (CD) spectroscopy. In addition, their cytotoxicities were assessed using several cancer cell lines, with 1 and 2 exhibiting modest activities.

Study of chemical states of lanthanoid nitrate in solution by electrospray ionization and fast atom bombardment mass spectrometry

Lanthanoids (Ln) are used in batteries, magnets and various industrial materials. Due to wide applications and few resources, efficient methods for the recovery of Lns are required. In this study, the soluble states of Ln in aqueous and organic phases were directly observed by electrospray ionization mass spectrometry (ESI-MS). We used La(NO3)3, Pr(NO3)3, and Tb(NO3)3 as representatives of Ln in our studies. When La(NO3)3, and Tb(NO3)3 was dissolved in water at pH 4.7, [La2(NO3)3(H2O)n]3+ (n = 0, 3) or [La2(NO3)(OH)2(H2O)m]+ (m = 9, 10), were observed. When La(NO3)3, Pr(NO3)3, and Tb(NO3)3 were dissolved at pH 1.8, [La2(NO3)3(H2O)n]3+ (n = 0, 3, 6, 9), [Pr2(NO3)(OH)2(H2O)7]3+, [Tb2(NO3)(OH)2(H2O)n]3+ (n = 6, 9, 12, 15, 18) were mainly observed. Particularly, in the Pr and Tb solutions, monomers generated were identified. By fast atom bombardment mass spectrometry (FAB-MS), monomer of Ln was not observed but dimer with glycerin was observed. This indicated that monomer was sufficiently hydrated to be ionized by FAB-MS. But dimer with glycerin was ionized due to less hydration by FAB-MS.On the other hand, when La, Pr, and Tb were extracted with TOPO in hexane solution at pH 1.8, [Ln(NO3)2-3TOPO]+, [Ln(NO3)2-4TOPO]+, and the monomers and dimers of TOPO (Ln = La, Pr, and Tb) were observed. This ESI-MS method could be useful for identifying chemical species in both aqueous and organic solutions.

Site-specific glycoproteomic characterization of ES-62: The major secreted product of the parasitic worm Acanthocheilonema viteae.

ES-62 is the major secreted product of the parasitic filarial nematode Acanthocheilonema viteae and has potent anti-inflammatory activities as a consequence of posttranslational decoration by phosphorylcholine (PC). Previously, we showed that ES-62’s PC was attached to N-linked glycans, and using fast atom bombardment mass spectrometry, we characterized the structure of the glycans. However, it was unknown at this time which of ES-62’s four potential N-glycosylation sites carries the PC-modified glycans. In the present study, we now employ more advanced analytical tools—nano-flow liquid chromatography with high-definition electrospray mass spectrometry—to show that PC-modified glycans are found at all four potential N-glycosylation sites. Also, our earlier studies showed that up to two PC groups were detected per glycan, and we are now able to characterize N-glycans with up to five PC groups. The number per glycan varies in three of the four glycosylation sites, and in addition, for the first time, we have detected PC on the N-glycan chitobiose core in addition to terminal GlcNAc. Nevertheless, the majority of PC is detected on terminal GlcNAc, enabling it to interact with the cells and molecules of the immune system. Such expression may explain the potent immunomodulatory effects of a molecule that is considered to have significant therapeutic potential in the treatment of certain human allergic and autoimmune conditions.

Isolation, characterization and DFT studies of epoxy ring containing new withanolides from Withania coagulans Dunal

A new withanolide named as withacoagulin J (1) along with a known withanolide H (2) from Withania coagulans Dunal are reported in this paper. The isolated compounds were elucidated by using 1D-NMR (1H NMR, 13C NMR) and 2D-NMR including homonuclear (COSY, NOESY) and heteronuclear (HSQC, HMBC); along with Mass spectrometry, UV-Visible and IR spectroscopic techniques. The molecular formula based on Fast-Atom Bombardment Mass Spectrometry [FAB-MS (M + 1)] for 1 and 2 were deduced as C28H37O5 and C28H39O6 with m/z values 453.2624 and 471.6041, respectively. The quantum mechanical studies of both compounds are based on DFT calculations. The DFT studies show band gaps of 4.86 and 4.83 eV for 1 and 2, respectively. The band gaps of 1 and 2 reflect high stability and resistivity towards oxidation-reduction reactions. The energies of HOMO and LUMO for compound 1 are -6.11 and -1.25 eV and for compound 2: -6.47 and -1.64 eV respectively. Theoretical and experimental FTIR data closely match for both the compounds which support the high accuracy of the computational protocol selection. Other parameters such as bond lengths, bond angles and dihedral angles for both compounds are also studied.

Synergistic Effect of Two Major Components of Malva verticillata in the Recovery of Alloxan-Damaged Pancreatic Islet Cells in Zebrafish.

Malva verticillata (Chinese mallow) has long been used in traditional medicines and herbal teas in Asia. The n-BuOH fraction (Fr) from M. verticillata promoted significant recovery of alloxan-damaged (AXD) pancreatic islets (PIs) in zebrafish (ZF). Two major components were isolated from M. verticillata through repeated-column chromatography. Based on several spectroscopic methods, including nuclear magnetic resonance (NMR), infrared spectroscopy (IR), and fast atom bombardment-mass spectrometry (FAB-MS), the chemical structures of compounds 1 and 2 were determined. In addition, the quantity of both compounds in the n-BuOH Fr was investigated through high-performance liquid chromatography (HPLC) and the quantities of compounds 1 and 2 in the n-BuOH Fr were determined to be 5.58% ± 0.16% and 2.85% ± 0.13%, respectively. The n-BuOH Fr, compounds 1 and 2, and the mixture of compounds 1 and 2 (MX, 1 and 2, the ratio of both compounds in n-BuOH Fr, 1.96:1) were evaluated for their ability to recover AXD PIs and for their KATP channel-blocking mechanism using diazoxide in ZF. The n-BuOH Fr (10 μg/mL) and compounds 1 and MX (1 μg/mL) exhibited a recovery effect on AXD PIs. The n-BuOH Fr (10 μg/mL) and MX (1 μg/mL) were also confirmed to be useful KATP channel activators. A synergistic effect of MX in the recovery of AXD PIs was first confirmed in ZF, and it was discovered that 2 acted as an insulin sensitivity activator that increased the activity of compound 1.

Cell cycle arrest and apoptosis in human liver cancer cell line and A549 cell lines by Turbiconol– A novel sterol isolated from Turbinaria conoides

Background: Turbinaria conoides, a brown seaweed, is a rich source of oxygenated fucosterols which are capable of suppressing the proliferation of cancer cells. Their specific therapeutically significant biological activity is directly related to the unique structural features of the molecule. This study specifically focuses on extracting unconventional sterol molecules (side chain extension) from this seaweed which can be used as a lead molecule to evolve therapeutical agents. Materials and Methods: To isolate unconventional sterol molecule, for structural elucidation and bioactivity study, sufficient amount of T. conoides was collected from Mandapam, an unique biodiverse environment along the Southeast coast of India. State-of-the-art methods available for the purification and characterization of molecule (High-resolution fast-atom bombardment mass spectrometry, ultraviolet-visible spectroscopy, attenuated total reflection–fourier transform infra-red, One-dimensional nuclear magnetic resonance, and two-dimensional nuclear magnetic resonance) were put in. In vitro bioassays (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium bromide, double staining, and flowcytometry) were carried out against A549 and human liver cancer cell line (HepG2) malignant cells to assess the cytostatic potential. Data were statistically validated. Results: A unique unconventional sterol molecule (Turbiconol) with ethyl and methyl group at C-27 was isolated. This molecule induced apoptosis in A549 and HepG2. However, cell cycle assessment revealed G0/G1 cell cycle arrest in Hep G2 and G2/M checkpoint was responsible for the suppression of A549 cell line. Conclusion: A novel unconventional compound, turbiconol, is reported in this study. In vitro results highlight the potential of this molecule in developing therapeutical combination which can be used for novel treatment methods.

A green chemical oligomerization of phloroglucinol induced by plasma as novel α-glucosidase inhibitors.

A new facile method was developed for simple green synthesis of methylene-bridged phloroglucinol oligomers using nonthermal dielectric barrier discharge (DBD) plasma in methanolic solution. The chemical structures of these newly generated oligomers 2-5 were determined by interpretation of the spectroscopic data, and the inhibitory activity toward α-glucosidase of all isolates was evaluated. The unusual phloroglcuinol pentamer 5 connected by four methylene linkages showed a much higher potential inhibitory effect against α-glucosidase than the other generated oligomers 2-4 and appeared to be a promising lead for development as a potential antidiabetic agent. Abbreviations: T2DM, type2 diabetes mellitus; DBD, dielectric barrier discharge; HPLC, high-performance liquid chromatography; IC50, 50% inhibition concentration; NMR, nuclear magnetic resonance; FABMS, fastatom bombardment mass spectrometry.

Synthesis of a Novel α-Glucosyl Ginsenoside F1 by Cyclodextrin Glucanotransferase and Its In Vitro Cosmetic Applications.

Ginsenosides from Panax ginseng (Korean ginseng) are unique triterpenoidal saponins that are considered to be responsible for most of the pharmacological activities of P. ginseng. However, the various linkage positions cause different pharmacological activities. In this context, we aimed to synthesize new derivatives of ginsenosides with unusual linkages that show enhanced pharmacological activities. Novel α-glycosylated derivatives of ginsenoside F1 were synthesized from transglycosylation reactions of dextrin (sugar donor) and ginsenoside F1 (acceptor) by the successive actions of Toruzyme®3.0L, a cyclodextrin glucanotransferase. One of the resultant products was isolated and identified as (20S)-3β,6α,12β-trihydroxydammar-24ene-(20-O-β-D-glucopyranosyl-(1→2)-α-D-glucopyranoside) by various spectroscopic characterization techniques of fast atom bombardment-mass spectrometry (FAB-MS), infrared spectroscopy (IR), proton-nuclear magnetic resonance (1H-NMR), 13C-NMR, gradient heteronuclear single quantum coherence (gHSQC), and gradient heteronuclear multiple bond coherence (gHMBC). As expected, the novel α-glycosylated ginsenoside F1 (G1-F1) exhibited increased solubility, lower cytotoxicity toward human dermal fibroblast cells (HDF), and higher tyrosinase activity and ultraviolet A (UVA)-induced inhibitory activity against matrix metalloproteinase-1 (MMP-1) than ginsenoside F1. Since F1 has been reported as an antiaging and antioxidant agent, the enhanced efficacies of the novel α-glycosylated ginsenoside F1 suggest that it might be useful in cosmetic applications after screening.

Penetration of an antimicrobial zinc-sugar alcohol complex into Streptococcus mutans biofilms

Mature biofilms are highly resistant to antimicrobial agents due to the presence of extracellular polymeric substances (EPS), which inhibit the penetration of external molecules. In this study, we developed a coordination compound consisting of zinc chloride and erythritol that exhibits penetrating and bactericidal activity against Streptococcus mutans biofilms. An in vitro biofilm model was established in microplates, and bactericidal activity against biofilms was evaluated using an Alamar blue assay. The cause of the antimicrobial activity of the zinc-erythritol mixture on mature biofilms was demonstrated using fast atom bombardment-mass spectrometry, confocal laser scanning microscopy and atomic force microscopy. We demonstrated that zinc chloride spontaneously formed cationic complexes with erythritol in water. The zinc-erythritol complexes reduced intra- and inter-molecular interactions between bacterial exopolysaccharides, a major component of EPS. This activity was confirmed by measuring the attenuation of the hardness of dried polysaccharides isolated from S. mutans biofilms. The reduction in the interactions between polysaccharides allowed the complexes to penetrate into biofilms and kill the embedded bacteria. While approximately 13% of biofilm-associated microbes were killed by a 10 min treatment with 6.6 mM zinc chloride, 45% were killed when a solution containing 19.8 mM erythritol and 6.6 mM zinc chloride was used. This strategy of leveraging the coordination properties of metal ions with sugar alcohols provides a simple way to effectively remove mature biofilms using only conventional substances without the need for intricate chemical synthesis processes.

Visible Light-Driven Dye-Sensitized Photocatalytic Hydrogen Production by Porphyrin and its Cyclic Dimer and Trimer: Effect of Multi-Pyridyl-Anchoring Groups on Photocatalytic Activity and Stability

The monomer, dimer, and trimer of 5,15-diphenyl-10,20-di(pyridin-4-yl)porphyrin are used to investigate the multianchoring effect on TiO2 for visible light-driven photocatalytic hydrogen production in a water medium. Further, the porphyrin trimer is prepared and analyzed by nuclear magnetic resonance (NMR) spectroscopy, absorption spectroscopy, electrochemical voltammetry, fast atom bombardment (FAB) mass spectroscopy, and density functional theory (DFT) computation. The results of this study indicate that the peak intensities of the absorption spectra increase as the number of porphyrin units increases, while changes could be barely observed in the highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gaps. The porphyrin dimer in a 1 wt % Pt-loaded TiO2 powder photocatalyst system exhibited optimal hydrogen production performance in a stable state over a period of 80 h and at a superior rate of 1023 μmol·g–1·h–1. Further, the stability of the photocatalytic system was syste...

Isolation, spectroscopic and density functional theory of two withanolide glycosides

Spectroscopic studies-based on 1D (1H NMR, 13C NMR), 2D-NMR (COSY, HMBC, HSQC), UV–visible, FTIR techniques and quantum chemical studies established on the density functional theory (DFT) were carried out for the natural withanolide glycosides, isolated from Withania Coagulans Dunal. The new glycoside withanolide named as (20R,22R)-14α,17,20β,27-trihydroxy-1-oxowitha-5,24-dienolide-27β-(O-β-d-glucopyranoside) (1), and a known withanolide (20R,22R)-14α-20β,27-trihydroxy-1-oxowitha-5,24-dienolide-3β-(O-β-d-glucopyranoside) (2) are reported here from W. coagulans. The molecular mass of these compounds were confirmed through Fast Atom Bombardment Mass Spectrometry (FAB-MS). Geometric and spectroscopic detailed were obtained from DFT calculations. 1H and 13C NMR theoretical values were found a little higher than the experimental values, but the trend in the chemical shift correlates well with the experimental values. The RMSD values of 1H and 13C NMR of 1 and 2 were 0.4 and 0.38, and 4.94 and 5.02 respectively. The calculated band gap was found 4.93 and 5.00 eV for 1 and 2 respectively which indicated the stable nature of these compounds towards redox reactions.

Ormosanine from Akebia quinata suppresses ethanol-induced inflammation and apoptosis and activates antioxidants via the mitogen activated protein kinase signaling pathway

We investigated the hepatoprotective, anti-inflammatory, anti-apoptosis, and antioxidant effects of ormosanine from Akebia quinata in a rat model of ethanol-induced liver injury. Ormosanine was identified and isolated by high-performance liquid chromatography and fast atom bombardment mass spectrometry. Oral administration of ormosanine significantly reduced the serum and liver levels of liver injury markers (alanine aminotransferase, aspartate aminotransferase, total cholesterol, and triglyceride). In addition, ormosanine significantly inhibited ethanol-induced cytochrome P450 2E1 activation and upregulated the levels of ALDH2. Ormosanine suppressed pro-inflammatory cytokines (tumor necrosis factor-alpha, cyclooxygenase-2, and interleukin-6) and downregulated apoptosis-related proteins (p53, cytochrome C, procaspase-3, poly[ADP-ribose] polymerase 1) by upregulating the phosphorylated-AKT, JNK, and extracellular signal regulated kinase pathways. Ormosanine exhibited antioxidant activity by upregulating superoxide dismutase, glutathione S-transferase, and B-cell lymphoma 2. Therefore, ormosanine plays an important role as a free radical-scavenger and may help prevent as well as alleviate ethanol-induced liver injury.

Carapanosins D-F from the Seeds of Andiroba (Carapa guianensis, Meliaceae) and Their Effects on LPS-Activated NO Production.

A novel nor-phragmalin-type limonoid, named carapanosin D (1), and two novel mexicanolide-type limonoids, carapanosins E (2) and F (3), were isolated from the seed oil of andiroba (Carapa guianensis Aublet), a traditional medicine in Brazil and Latin American countries. Their structures were unambiguously determined on the basis of spectroscopic analyses using one-dimensional (1D) and two-dimensional (2D) NMR techniques and High resolution Fast Atom Bombardment Mass Spectrometry (HRFABMS). Compounds 1–3 were evaluated for their effects on the production of nitric oxide (NO) in Lipopolysaccharide (LPS)-activated mouse peritoneal macrophages. The NO inhibitory assay suggested that compounds 2 and 3 have high potency as inhibitors of macrophage activation.

Meet the Editors: David R. Goodlett

Meet the Editors: David R. Goodlett

Crystal Structures of 2,2′-Bipyridyl Palladium(II) Complexes: [Pd(PPh3)2{κ1-C10H6N2Br}(Br)] and [Pd(PPh3)2Br]2{μ,κ2-C10H6N2}

A reaction of Pd(PPh3)4 (complex 1) and 6,6′-dibromo-2,2′-bipyridyl C10H6N2Br2 in a 1:1 molar ratio or 2:1 produces a mononuclear [Pd(PPh3)2{κ1-C10H6N2Br}(Br)] complex (2) and a binuclear [Pd(PPh3)2Br]2{μ,κ2-C10H6N2}complex (3). In complex 3, the 2,2′-bipyridyl ligand is coordinated through two C and two metal (Pd) centers and bridges two Pd atoms to the trans-N of the 2,2′-bipyridyl ligand. The crystal characteristics are outlined as follows: space group P2(1)/n, Z = 2, a = 9.2008(4) A, b = 14.5268(6) A, c = 30.6609(13) A, α = 90, β = 91.3415(13), and γ = 90°. Complexes 2 and 3 are characterized through elemental analyses, fast atom bombardment mass spectrometry, 1H, 13C, and 31P nuclear magnetic resonance spectroscopy, and single crystal X-ray diffraction.