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Seven Zn-dithiocarbamate complexes were suggested as corrosion inhibitors. Density functional theory (DFT) was used to predict the ability of inhibition. Room temperature conditions were applied to suggest the optimization of complexes, physical properties, and corrosion parameters. In addition, the HOMO, LUMO, dipole moment, energy gap, and other parameters were used to compare the inhibitors efficiency. Gaussian 09 software with LanL2DZ basis set was used. Total electron density (TED) and electrostatic surface potential (ESP) were utilized to show the sites of adsorption according to electron density.

Treatment of 1,4-benzothiazin-3-one (Hbto) with mercury(II) acetate Hg(OAc)2 in 2:1 mol ratio affords [Hg(bto)2] (1) in 99% yield. The resulted complex was used as a synthon to prepare new mixed-ligand complexes with monophosphines or diphosphines of the types [Hg(bto)2(L)2] or [Hg(bto)2(L-L)]; where L = triphenylphosphine (Ph3P) (2) or triphenylphosphinesulfide (Ph3PS) (3); L-L = 1,2-bis(diphenylphosphino)ethane (dppe) (4) or 1,1′-bis(diphenylphosphine)ferrocene (dppf) (5). FTIR, 1H NMR, 13C NMR, 31P-{1H} NMR, molar conductivity and elemental analysis were used to characterize the resulted complexes. Results suggest that 'bto' ion in [Hg(bto)2] (1) is linked to mercury ion via exocyclic oxygen and endocyclic nitrogen atoms in a chelating bidentate fashion while in the complexes (2–5), it is linked to mercury ion via endocyclic nitrogen atom in a monodentate fashion. Furthermore, to take benefit of mercury complexes which were classified as toxic compounds, [Hg(bto)2] (1) complex has been evaluated for its susceptibility to hydrogen storage. The result of H2 storage showed that this complex can store 1.42 wt% of hydrogen under 88 bar and 77 K.

Six N-acetamide complex, [Pd(bzta)2](1a), [Pd(bzmta)2](1b) and [Pd(bzcta)2](1c), [Pt(bzta)2] (2a), [Pt(bzmta)2](2b) and [Pt(bzcta)2](2c) {bztaH: N-(1,3-benzothiazol-2-yl)acetamide, bzmtaH: N-(6-methyl-1,3-benzothiazol-2-yl)acetamide, bzctaH: N-(6-chloro-1,3-benzothiazol-2-yl) acetamide} have been prepared and characterized by NMR (1H & 13C, 1H-1H COSY), infrared and UV–visible technique, elemental analysis, and molar conductivity. The spectroscopic data is in agreement with the coordination of acetamide to Pd(II) and Pt(II) through the N atom of the heterocyclic ring and the deprotonated oxygen atom of the amide group. The anticancer effect of 1a, 1b, 2a, and 2b were examined against three different cancer cell lines, Lung (A549), ovarian (A2780), and Melanoma (518A2). It's clear that the results revealed that the cytotoxic effect of 1a, 1b, 2a, and 2b was different against the cell lines. Density functional theory (DFT) was used to investigate the structure and stability of the compounds by calculating the highest unoccupied molecular orbital (HUMO), lowest unoccupied molecular orbital (LUMO), band gap energies, and frequency calculations.

The reaction of the equimolar ratio of ammonium pyrrolidinedithiocarbamate {(NH4)PyDT} and sodium N,N-diethyldithiocarbamate (NaEt2DT) with the divalent ion salts of zinc, cadmium and mercury resulted in the complexes of the type [M(κ2-PyDT)(κ2-Et2DT)]; {M(II) = Zn, Cd, Hg}. These complexes were characterized using different techniques: elemental analysis, molar conductivity, FTIR, 1H NMR, 13C{1H} NMR and HSQC. The results demonstrate the bidentate chelating mode of the two dithiocarbamate ligands through the sulfur atoms to afford a tetrahedral geometry around the metal ion. Surprisingly, these coordination compounds were obtained as nanocomplexes with regular geometrical nanostructures as follows; [Zn(κ2-PyDT)(κ2-Et2DT)] (1) as nanosheets with a thickness of 21–24 nm, [Cd(κ2-PyDT)(κ2-Et2DT)] (2) as nanorods with a diameter of 70–380 nm while [Hg(κ2-PyDT)(κ2-Et2DT)] (3) was found as merged nanospheres with a diameter of 54–70 nm. These nanostructures have been demonstrated using the SEM and X-ray diffraction of the powder.

Background Little phosphorus availability in soil is one of the major forces for crop production. Phosphate solubilizing fungi enhance available phosphorus from soils and contribute to achieve the plants phosphorus requirement. Phosphate solubilizing fungi are important component of soil microbiota and play an essential role in the biogeochemical cycling of phosphorus in natural ecosystems. Results The study tested the potential of the isolated phosphate solubilizing fungi to inhibit the growth of Alternaria alternata, Fusarium solani, Geotrichum candidum, Rhizoctonia solani and Sclerotium rolfsii. A total of 137 fungal isolates were isolated and identified from 30 soil samples. Nine isolates solubilized inorganic phosphate (tricalcium phosphate). Eight of these isolates were isolated from the rhizosphere of Alhagi graecorum Boiss., Allium cepa L., Ehrharta calycina Sm., Ludwigia stolonifera (Guill. & Perr.) Raven, Mentha longifolia L., Phragmites communis Trin.,Triticum aestivum L. and Zea mays L., respectively and one isolate was isolated from island's free soil. Purified single spore cultures of these nine isolates were identified to species level by multi loci DNA barcoding using internal transcribed spacer1and 2 (ITS1 and ITS 2) of the rRNA gene cluster, Calmodulin (CaM) and β-tubulin)BenA) gene markers. Conclusions The isolated phosphate solubilizing fungi belonged to two genera, Aspergillus and Penicillium. The phosphate solubilization index ranged from 1 to 1.5. Aspergillius japonicus 2 had the highest solubilization index (1.5) and also had the highest inhibition percentage (70%) against Alternaria alternata. This isolate is promising for development of biocontrol agent of Fusarium solani, Geotricum candidium and Alternaria alternata. The highest phosphate solubilization by Aspergillius japonicus 2 was obtained by using sucrose as carbon source and also ammonium chloride and tryptophan as nitrogen source. The highest solubilization percentage was 78.2% at optimum glucose concentration (5%) while the pH value that gave the highest solubilization percentage (90%) was 3. After eight days of incubation of Aspergillius japonicus 2, the solubilization percentage reached its maximum value (80.2%).

Treatment of the chelated palladium(II) complex, trans-[Pd(K2-Sac-CH2O)2].2H2O with one mole equivalent of the diammines (L-L), L-L = 2,2'-bipyridine (bipy),. ethylene diamine (en), 1,10-phenanthroline (phen), or N,N-dimethyl ethylene diammine (dmen) in EtOH solvent afforded mixed ligand complexes of the type [Pd(K1-Sac-CH2O)2(L-L)] in 82-93% yield. While treatment of trans-[Pd(K2-Sac-CH2O)2].2H2O with two mole equivalents of the monoamines (L), L=pyridine (py), 3-methylpyridine (3-mpy) or 3-aminopyridine (3-apy) in EtOH solvent gave trans-[Pd(K1-Sac-CH2O)2(L)2] complexes in 86-89% yield The prepared complexes were characterized by elemental CHN analysis, .conductivity measurements,. infrared and 1H nmr spectra.

Ten transition metal dithiocarbamate (DTC)complexes of the type [M(κ 2‐Et2DT)2] (1–5), and [M(κ 2‐PyDT)2] (6–10) (where M = Co, Ni, Cu, Pd, and Pt; Et2DT = diethyl dithiocarbamate; PyDT = pyrrolidine dithiocarbamate) were synthesized and characterized by different methods. The dithiocarbamate acted as bidentate chelating ligands to afford a tetrahedral complexes with Co(II) ion and square planner with other transition metal ions. The dithiocarbamate complexes showed good activity against the pathogen bacteria species. The results showed the Pt‐dithiocarbamate complexes are more active against all the tested bacteria than the Pd‐dithiocarbamate complex. The dithiocarbamate complexes displayed the maximum inhibition zone against E. coli bacteria, whereas the lowest activity of the dithiocarbamate against Salmonella typhimurium bacteria. The cytotoxicity of the Pd(II) and Pt(II) complexes was screened against the MCF‐7 breast cancer cell line and the complexes showed moderate activity compared with the cis‐platin. The results indicated that the MCF7 cells treated with 500 μg\ml of ligands and Pd(II) and Pt(II) complexes after 24 hr exposure showed intercellular space and dead cells. Finally, molecular docking studies were carried out to examine the binding mode of the synthesized compounds against the proposed target; SARS COV2 RNA‐dependent RNA polymerase., Transition metal dithiocarbamate complexes of the type [M(κ 2‐Et2DT)2] (1–5), and [M(κ 2‐PyDT)2] (6–10) (Where M = Co, Ni, Cu, Pd, and Pt; Et2DT = Diethyl dithiocarbamate; PyDT = Pyrrolidine dithiocarbamate) were synthesized and characterized. The dithiocarbamate (DTC) act as bidentate chelating ligands to afford a tetrahedral complexes with Co(II) ion and square planner with other transition metal ion. The dithiocarbamate complexes showed good activity against the pathogen bacteria species. The cytotoxicity of the Pd(II) and Pt(II) complexes was screened against MCF‐7 breast cancer cell line and the complexes showed moderate activity compared with the cis‐platin. Finally, molecular docking studies were carried out to examine the binding mode of the synthesized compounds against the proposed target; SARS COV2 RNA‐dependent RNA polymerase.

A novel 2- [-2-(4, 5-dimethyl thiazolyl) azo] -5-dimethyl amino benzoic acid) was synthesized from 2-amino-4,5- dimethyl thiazole. The azo ligand was obtained by the diazotization of 2-amino-4,5- dimethyl thiazole and coupling with 3-dimethyl amino benzoic acid in an alkaline alcoholic solution. Compounds were characterized by spectroscopic methods such as (1H, 13C NMR, UV–Vis, FT-IR) mass spectra, and XRD diffraction. In addition to, standard characterization techniques that including elemental analysis, thermal gravimetric analysis, molar conductivity, and FESEM. These studies revealed octahedral geometries around the Co(III) and Cd(II) ions. The prepared compound was a screen for their bioactive such as streptococcusEscherichia coli, and Penicillium.sp. Moreover, Anticancer activity of the new ligand and Co complex was tested against breast carcinoma cell (MCF-7) cell lines by MTT assay and results revealed that the synthesized complex exhibited a good anticancer activity a promising candidate for future anti-cancer drugs. Also, the theoretical section was used to determine the physical characteristics and inhibitory activity of cancer cells via docking.

Highlights • Synthesis new Schiff bases and characterized by IR, NMR and elemental analysis. • In vitro antibacterial activity were investigated. • Calculations of the density functional theory • The synthetic compounds have also been docked with 3-chymotrypsin-like protease (3CLpro)., New Schiff bases {N'-(phenyl(pyridin-2-yl)methylene) isonicotinohydrazide (L1H), N1-(naphthalen-1-yl)-N2-(phenyl(pyridin-2-yl) methylidene) ethane-1,2-diamine (L2H), N-(6-chlorobenzo[d]thiazol-2-yl)-1-phenyl-1-(pyridin-2-yl) methanimine (L3H)}were synthesized by reaction of 2-benzoylpyridine with different amines (2-amino-6-chlorobenzothiazole, isonicotinohydrazide and N1-(naphthalen-1-yl)ethane-1,2-diamine) and characterized by 1H-NMR, 13C-NMR, IR mass spectroscopy and elemental analysis. The compounds were assayed by the disc diffusion method for anti-bacterial against five pathogenic bacteria species (Staphylococcus aureus, Micrococcus luteus, Staphylococcus pyogenes, Bacillus subtilis, and E. coli). All prepared Schiff bases showed good activity compared to positive control (streptomycin), Moreover the L3H showed the highest activity against S. aureus, and M. luteus than the other compounds and streptomycin. In additional molecular docking studies with 3-chymotrypsin-like protease (3CLpro), the essential enzyme for SARS-CoV-2 proliferation. The rest of compounds have shown promising results as 3CLpro inhibitors interacting with the active sites of the enzymes. Finally, DFT 's estimated electrostatic molecular potential results were used to illustrate the molecular docking findings. The DFT calculations showed that L3H has the highest dipole moment and electrophilicity index. Interestingly, L2H of the largest energy gap ∆E = 2.49 eV, there are several hydrophilic interactions that could facilitate the binding with the receptors. All of these parameters could be shared to significantly affect the protein sites of binding affinity with different extent.

Treatment of one molar equivalent of [M(HCPPT)2] (M=Pd, Pt; H2CPPT = 1-(5-chloropyridin-2-yl)-3-phenylthiourea) with one molar equivalent of κ2-diphos (diphos = dppe, dppp, dppb, and dppf) or two molar equivalent of κ1-phos afforded eight heterocyclic thiourea dianion complexes (1-8). The spectroscopic data analysis showed clear AX splitting pattern, which indicates that the two coordinated phosphorus atoms are non-equivalent. Meaning that, the metal's center is attached to both S,N donor atoms in a chelating fashion. In addition, the splitting system show a good resemblance to the previously synthesized thiourea dianion complexes. Furthermore, the reaction is believed to undergo a square planar substitution mechanism at which five coordinate intermediate is formed. Generally, the reported complexes (1-8) are believed to resemble their analogues thiourea dianion complexes at which a four membered ring structure is formed with Pt(II) or Pd(II) being centered, adopting a square planar geometry. Four of the synthesized complexes (1-4) were tested against Salmonella typhimurium and Bacillus subtilis bacteria at which complexes 4 and 2 showed highest activity values.

Treatment of two molar equivalents of 1,8-diaminonaphthalene-2-thione with one molar equivalent of the metal's(II) salt (Pd, Pt, Hg, Cd, Zn) afforded both neutral thione complexes and thionate derived complexes. The prepared ligand and its complexes (1-8) were characterized via different spectroscopic technics including: FT-IR, 1H, 13C-NMR, and mass spectroscopy. The spectroscopic data analysis suggested that these compounds adopt different structural geometries. For instance, Pd(II) and Pt(II) complexes show square planar geometry. Whereas, thione complexes of Hg(II), Zn(II), and Cd(II) showed probable tetrahedral structure. However, thionate derived complexes of Hg, and Ph-Hg are expected to be linear. The thionato-Cd(II) complex show bidentate chelating mode through its N and S donor atoms. Furthermore, the newly prepared complexes exhibit nano-structural characteristics, which were measured by SEM and X-Ray diffraction of the powder. SEM data showed that complexes from (3, 5) and (8) gave irregular nano-structure, nano-rod structure, and nano-sphere structural pattern respectively. On the other hand, Complexes (1) and (2) were tested against MCF-7 (breast) and LoVo (colon) cancer cells using MTT assay. It was found that the palladium complex showed a promising antiproliferative activity against colon (LoVo) and breast (MCF-7) cancer cells with IC50 values 21.13 and 22.25 µM respectively. In addition the anti-bacterial activity was study against two different pathogenic bacteria, and the Pd(II) complex displayed highest activity compared with other complexes.

This study aims at exploiting salinity stress as an innovative, simple, and cheap method to enhance the production of antioxidant metabolites and enzymes from bacteria for potential application as functional additives to foods and pharmaceuticals. We investigated the physiological and biochemical responses of four bacterial isolates, which exhibited high tolerance to 20% NaCl (wt/vol), out of 27 bacterial strains isolated from Aushazia Lake, Qassim region, Saudi Arabia. The phylogenetic analysis of the 16S rRNA genes of these four isolates indicated that strains ST1 and ST2 belong to genusBacillus, whereas strains ST3 and ST4 belong to genusPlanococcus. Salinity stress differentially induced oxidative damage, where strains ST3 and ST4 showed increased lipid peroxidation, lipoxygenase, and xanthine oxidase levels. Consequently, high antioxidant contents were produced to control oxidative stress, particularly in ST3 and ST4. These twoPlanococcusstrains showed increased glutathione cycle, phenols, flavonoids, antioxidant capacity, catalase, and/or superoxide dismutase (SOD). Interestingly, the production of glutathione byPlanococcusstrains was some thousand folds greater than by higher plants. On the other hand, the induction of antioxidants in ST1 and ST2 was restricted to phenols, flavonoids, peroxidase, glutaredoxin, and/or SOD. The hierarchical analysis also supported strain-specific responses. This is the first report that exploited salinity stress for promoting the production of antioxidants from bacterial isolates, which can be utilized as postbiotics for promising applications in foods and pharmaceuticals.

It is well known that the quality and quantity of bioactive metabolites in plants and microorganisms are affected by environmental factors. We applied heat stress as a promising approach to stimulate the production of antioxidants in four heat-tolerant bacterial strains (HT1 to HT4) isolated from Aushazia Lake, Qassim Region, Saudi Arabia. The phylogenetic analysis of the 16S rRNA sequences indicated that HT1, HT3 and HT4 belong to genus Bacillus. While HT2 is closely related to Pseudooceanicola marinus with 96.78% similarity. Heat stress differentially induced oxidative damage i.e., high lipid peroxidation, lipoxygenase and xanthine oxidase levels in HT strains. Subsequently, heat stress induced the levels of flavonoids and polyphenols in all strains and glutathione (GSH) in HT2. Heat stress also improved the antioxidant enzyme activities, namely, CAT, SOD and POX in all strains and thioredoxin activity in HT3 and HT4. While GSH cycle (GSH level and GPX, GR, Grx and GST activities) was only detectable and enhanced by heat stress in HT2. The hierarchical cluster analysis of the antioxidants also supported the strain-specific responses. In conclusion, heat stress is a promising approach to enhance antioxidant production in bacteria with potential applications in food quality improvement and health promotion.

Palladium(II)-Salicylanilide complexes of the type [Pd(k2-Saln)2] (1), [Pd(k2-Saln)2(diphos)] (2-6) (diphos = dppe, dppp, dppb, dppf, and dppmS2) and [Pd(k2-Saln)2(m-dppm)] (7) were synthesized and characterized. The salicylanidate ligand (Saln-) was bonded as bidentate chelating through the O atoms of hydroxyl and carbonyl groups in complex (1), whereas coordinated as monodentate through the O atom of hydroxyl group in complexes (2-7), and the all diphosphine ligands except dppm bonded as bidentate chelating to afford a square planner geometry around the Pd(II) ion. The dppm ligand was coordinated as bidentate bridging to afford binuclear complex. The prepared complexes displayed respectable activity against the pathogen bacteria species. Complex (5) showed the highest inhibition value against all types of bacteria, compared to the other complexes and the free ligand. On the other hand, the complex [Pd(Saln)2], showed the lowest inhibition against all types of bacteria. And the inhibition sequence of complexes is as following:(5) > (4) > (2) > (3) > HSaln > (1)Calculations of density function theory (DFT) were performed at the B3LYP/6-311G(d,p) level involved in the Gaussian 09 program to inspect the optimized structures of the chelating agent and its complexes. Docking study of the ligand was performed against the proteins of bacterial strains Streptococcus pyogenes (ID: 5GOT), Escherichia coli (ID: 1C14), Staphylococcus aureus (ID: 3BL6), and Salmonella typhimurium (ID: 3V7F) by Schrodinger suite program using XP glide protocol.

New Co(II), Ni(II) and Cu(II) complexes with 2-meracapto-5-(2,4-dinitrophenyl)-1,3,4-oxadiazole (IpotH) or 2-meracapto-5-((4-(dimethylamino)benzylidene)amino)-1,3,4-thiadiazole (daptH) ligands, were prepared by treatment two moles of thione ligands with one mole of metal salts in EtOH/Acetone and H2O as a solvents, to afforded octahedral complexes of the types [MX2(k2-IpotH)2] (Where M = Co, Cu, X= Cl and M= Ni , X= NO3 ) or [MX2(k2-daptH)2] (Where M = Co, Cu, X= Cl and M= Ni , X= NO3 ). The thione ligands bonded through the nitrogen atom of heterocylic and sulfur atom of thiol group. The prepared ligands and its complexes were characterization by elemental analysis (CHNM), IR spectroscopy , molar conductivity, magnetic susceptibility, UV-Visible spectroscopy and 1H NMR data.

Reactions of [Pd(Me2NCH2C6H4-κ2N,C)(μ-Cl)]2 with two equivalents of sodium saccharinate (Nasac), thiosaccharin (Htsac) or sodium benzisothiozolinate (Nabit) results in the stepwise substitution of the bridging halides to form sequentially [Pd2(Me2NCH2C6H4-κ2N,C)2(μ-Cl)(μ-X)] (X = sac, tsac) and [Pd(Me2NCH2C6H4-κ2N,C)(μ-X)]2 (X = sac, tsac, bit). The molecular structures of all three disubstituted complexes are reported. In each the two metalated ligands bind in a chelate manner adopting a relative anti conformation, while the new ligands bridge the two palladium atoms adopting a relative cis conformation. The local conformation about each palladium differs with small ligand changes. Thus in the sac and bit complexes all nitrogens lie trans to one another, in the tsac complex they are cis. Conformational changes also lead to large differences in the non-bonded Pd…Pd distance which range over 0.5 A. Treatment of [Pd(Me2NCH2C6H4-κ2N,C)(μ-Cl)]2 with two equivalents of 2-amino-3-methylpyridine (ampyH) in the presence of NEt3 affords mononuclear [PdCl(Me2NCH2C6H4-κ2N,C)(ampyH-κ1N)] as a result of “bridge-splitting”, the ampyH ligand binding through the pyridyl-nitrogen and lying approximately perpendicular to the PdCClN2 plane as shown by a crystallographic study.

Palladium(II)-Salicylanilide complexes of the type [Pd(κ2-Saln)2] (1), [Pd(κ2-Saln)2(diphos)] (2-6) (diphos = dppe, dppp, dppb, dppf, and dppmS2) and [Pd(κ2-Saln)2(μ-dppm)] (7) were synthesized and characterized. The salicylanidate ligand (Saln−) was bonded as bidentate chelating through the O atoms of hydroxyl and carbonyl groups in complex (1), whereas coordinated as monodentate through the O atom of hydroxyl group in complexes (2-7), and the all diphosphine ligands except dppm bonded as bidentate chelating to afford a square planner geometry around the Pd(II) ion. The dppm ligand was coordinated as bidentate bridging to afford binuclear complex. The prepared complexes displayed respectable activity against the pathogen bacteria species. Complex (5) showed the highest inhibition value against all types of bacteria, compared to the other complexes and the free ligand. On the other hand, the complex [Pd(Saln)2], showed the lowest inhibition against all types of bacteria. And the inhibition sequence of complexes is as following: (5) > (4) > (2) > (3) > HSaln > (1) Calculations of density function theory (DFT) were performed at the B3LYP/6-311G(d,p) level involved in the Gaussian 09 program to inspect the optimized structures of the chelating agent and its complexes. Docking study of the ligand was performed against the proteins of bacterial strains Pseudomonas aeruginosa (ID: 3P3E), Escherichia coli (ID: 1C14), Staphylococcus aureus (ID: 3BL6), and Salmonella typhimurium (ID: 3V7F) by Auto-Dock tools to portend the best binding mode.

The addition of sodium hydroxide to a mixture of phenyl mercury acetate and 2-aminobenzothiazole in warm ethanol led to the high yield (84%) formation of [Ph-Hg(LH)]n (1), LH = the 2-cyanoaminothiaphenolate anion (SC6H4NHC N)−, resulting from monodeprotonation of 2-aminobenzothiazole and facile carbon–sulfur bond breakage. Reaction of 1 with Ph3P or Ph3PS afforded [Hg(LH)2(Ph3P)2] (2) or [PhHg(μ-LH)(Ph3PS)]2 (3), respectively. Recrystallization of 2 from warm DMSO afforded [Hg(μ-L)(PPh3)]2 (4), L = the 2-cyanoaminothiophenolate di-anion (SC6H4NC N)2−, which was characterized by an X-ray diffraction study. Treatment of 1 with the diphosphines Ph2P(CH2)nPPh2, 2,6-diaminopyridine (dapy), ethylenediamine (en) or 1,10-phenanthroline (phen) afforded [PhHg(LH){ Ph2P(CH2)nPPh2}], {n = 1 dppm (5), n = 2 dppe (6), n = 3 dppp (7), n = 4 dppb (8), (CH2)n = (Cp)2Fe dppf (9)}, [PhHg(LH)(dapy)2] (11), [PhHg(LH)(en)] (12) or [PhHg(LH)(phen)] (13). Recrystallization of 5 from CH2Cl2 afforded the binuclear complex [Hg(μ-L)(η1-dppm)]2.CH2Cl2 (10), which has been characterized by an X-ray diffraction study.

Reaction of mercury(II) acetate [Hg(Ac)2] or mercury(II) chloride [HgCl2] with two moles equivalent of Na[bit] (bit = benzisothiozolinate) afforded [Hg(bit)2] as white solid in 96 and 70% yield respectively. Treatment of [Hg(bit)2] with the bidentate ligands; 2,2-bipyridine (bipy), 1, 10-phenanthroline (phen) or ethylene diamine (en) in absolute ethanol afforded the complexes; [Hg(bit)2(bipy)], [Hg(bit)2(phen)] or [Hg(bit)2(en)] as white solids in 82–88% yields. The crystal structures of [Hg(bit)2(bipy)] and [Hg(bit)2(phen)] were determined, each showing a distorted tetrahedral geometry around mercury with the two benzisothiazolinate (bit) ligands being coordinated via nitrogen atom and lying almost perpendicular to each other. Reactions of [Hg(bit)2] with two moles equivalent of Ph3P in absolute EtOH at room temperature or one mole equivalent of 1,3-is(diphenylphosphino)propane (dppp) in boiling CHCl3, afford [Hg(bit)2(Ph3P)2] and a (2:1) mixture of [Hg(bit)2(κ2-dppp)] and [Hg(bit)2(μ2-dppp)]n. Treatment of [Hg(bit)2] with bis(diphenylphosphino)methane (dppm), afford [Hg(mbm)2] (Hmbm = 2-mercaptobenzamide), while treatment with bis(diphenylphosphino)butane afford [Hg(mbm)2(dppb)]. A sulfur-nitrogen bond breaking within the heterocyclic ring of the bit ligand took place followed by protonation of the nitrogen atom to afford the final product., We would like to thank Tikrit University for partial support of this work.

International audience; Supported cobalt and iron catalysts are important for many catalytic processes. It is believed that combining both elements in a bimetallic catalyst would result in a synergetic catalytic activity during Fischer−Tropsch Synthesis. However, the nature of the interaction between the two elements and its effect on their catalytic properties are not well understood. In the present work, we report the synthesis of carbon-nanotube-supported Co−Fe alloy catalysts using colloidal chemistry methods. The ratios of Co−Fe and their homogeneous distribution in the supported nanoparticles were confirmed using local and bulk characterization techniques. We observed the formation of Co−Fe Janus-like alloy structure and a change of their elemental distribution at the nanoparticle scale upon reduction. The bimetallic catalyst showed reasonable Fischer−Tropsch catalytic activity and selectivity to C 5+ hydrocarbons when compared with monometallic iron and cobalt catalysts. Finally, we found that the active phase of the Co−Fe bimetallic species during catalysis depends on the catalytic conditions.

Phosphines react with the benzisothiazolinate (bit) paddlewheel dimer, [Ni2(μ-bit)4·2H2O], resulting in sulfur–nitrogen bond scission and a series of unexpected transformations leading to novel Ni(ii) complexes containing 2-cyanophenylthiolate and related thiolate ligands.

Addition of sodium benzisothiazolinate, Na(bit), to metal salts MX2·nH2O (M = Mn, Co, Ni, Cu) affords a simple high yielding route to benzisothiazolinate-bridged paddlewheel dimers [M2(μ-bit)4·2H2O]. Upon reaction with amines these serve as useful synthons to access benzisothiazolinate chemistry. Addition of 4-aminopyridine (4-ampy) in ethanol leads to cleavage of dimers and formation of all trans-[M(4-ampy)2(κ1-bit)2(EtOH)2] (M = Co, Ni), the bit ligand binding in a monodentate fashion through the amide-nitrogen. With a slight excess of ethylenediamine (en) a similar cleavage occurs to afford trans-[M(κ1-bit)2(κ2-en)2] (M = Co, Ni, Cu). For nickel and copper, the intermediate five-coordinate mono-diamine derivatives cis-[M(κ1-bit)2(κ2-en)(H2O)] (M = Ni, Cu) have also been isolated. It is not necessary to isolate the dimers to access this chemistry; direct reactions of MX2·nH2O with either 1,4-bipyridine (bipy) or 1,10-phenanthroline (phen) and Na(bit) lead to cis-[M(κ1-bit)2(κ2-bipy)(H2O)2] (M = Co, Cu) and cis-[M(κ1-bit)2(κ2-phen)(H2O)L] (M = Mn, Co, L = H2O; M = Cu, L = EtOH) respectively. Molecular structures of [Cu2(μ -bit)4.2dmf]·2dmf, trans-[Co(4-ampy)2(κ1-bit)2(EtOH)2] and [Cu(κ1-bit)2(en)(H2O)]·H2O have been determined. This work highlights the easy accessibility of under exploited transition metal benzisothiazolinate chemistry and shows that this flexible ligand can adopt monodentate and bridging bidentate coordination modes.

Eight palladium(II) pyrrolidine dithiocarbamate complexes were prepared and fully characterized. Reactions of the dimeric cyclopalladated complexes, [Pd(ppy)(μ-Cl)]2 (ppyH= phenylpyridine) or [Pd(N-BAZ)(μ-Cl)]2 (N-BAZH = N,N-dimethylbenzylamine) with two moles equivalent of ammonium pyrrolidine dithiocarbamate NH4(PyDT) afford [Pd(PyDT)(ppy)] and [Pd(κ2-PyDT)(N-BAZ)] in good yield (91 and 71 % respectively). A crystal structure of [Pd(PyDT)(ppy)] reveals that the PyDT ligand is bonded as a bidentate chelate. Reaction of trans-[PdCl2(DMSO)2] with sodium benzisothiazolinate (NaBit), followed by NH4(PyDT) afford Na[Pd(PyDT)(N-Bit)2]. Diphosphine adducts [Pd(PyDT)2{Ph2P(CH2)nPPh2}] {n = 2-4 or (CH2)n = (C5H4)2Fe}, can be prepared in good yield upon addition of the diphosphine to [Pd(PyDT)2]. Reaction of trans-[PdCl2(PPh3)2] with sodium saccharinate (Nasac) followed by NH4(PyDT) afford trans-[Pd(PyDT)(N-sac)(PPh3)2]. The prepared complexes were characterized by elemental analysis, i.r., 1H, 31P nmr spectroscopic data and conductivity measurements.

The use of actinomycetes for improving soil fertility and plant production is an attractive strategy for developing sustainable agricultural systems due to their effectiveness, eco-friendliness, and low production cost. Out of 17 species isolated from the soil rhizosphere of legume crops, 4 bioactive isolates were selected and their impact on 5 legumes: soybean, kidney bean, chickpea, lentil, and pea were evaluated. According to the morphological and molecular identification, these isolates belong to the genus Streptomyces. Here, we showed that these isolates increased soil nutrients and organic matter content and improved soil microbial populations. At the plant level, soil enrichment with actinomycetes increased photosynthetic reactions and eventually increased legume yield. Actinomycetes also increased nitrogen availability in soil and legume tissue and seeds, which induced the activity of key nitrogen metabolizing enzymes, e.g., glutamine synthetase, glutamate synthase, and nitrate reductase. In addition to increased nitrogen-containing amino acids levels, we also report high sugar, organic acids, and fatty acids as well as antioxidant phenolics, mineral, and vitamins levels in actinomycete treated legume seeds, which in turn improved their seed quality. Overall, this study shed the light on the impact of actinomycetes on enhancing the quality and productivity of legume crops by boosting the bioactive primary and secondary metabolites. Moreover, our findings emphasize the positive role of actinomycetes in improving the soil by enriching its microbial population. Therefore, our data reinforce the usage of actinomycetes as biofertilizers to provide sustainable food production and achieve biosafety.

New palladium(II) and platinum(II) 1,1′-bis(diphenylphosphino) ferrocene (dppf) complexes with heterocyclic N-acetamide co-ligands [Pt(κ1-O-amp)(κ1-N-amp)(κ2-dppf)], [M(κ2-dap)(κ2-dppf)], (M= Pd, Pt, ampH = N-(2-pyridyl-3-methyl)acetamide, dapyH2 = 2,6-diacetamidopyridine) have been prepared and characterized. The salts K2[PtCl2(sac)2] and Na2[PdCl2(sac)2] have been prepared in excellent yield from the reactions of K2PtCl4 or Na2PdCl4 with Nasac in H2O or MeOH, respectively. Furthermore, the reaction products of the newly prepared salt, K2[PtCl2(sac)2] with diphosphines Ph2P(CH2)nPPh2 (n = 1–4), have been investigated.

The binuclear [Pd2(κ2-ptt)4] (1) and mixed ligand complexes of the type [Pd(κ1-S-ptt)2(κ2-diamine)] (2–4) (Hptt is 1-phenyl-1H-tetrazole-5-thiol), diamine; ethylene diamine (en), 1,10-phenanthroline (Phen) or 2,2′-bipyridyl (Bipy) as co-ligands have been synthesized. The obtained complexes were characterized by elemental analysis, 1H-, 13C-{1H} NMR, molar conductivity, UV–Vis and IR spectroscopy. In complex 1 the ptt anion coordinated as a bridging bidentate via the thione sulfur atom and deprotonated nitrogen atom of the heterocyclic ring to afford a dimeric complex. Whereas in 2–4 the ptt bonded as a monodentate through the thiolato sulfur atom, while the diamine ligands are coordinated as bidentate chelates to afford a square planner arrangement around the Pd(II) center. The anti-fungal activity of the prepared complexes (1–4) was tested against two fungi types (Candida albicans, and Aspergillus niger). All the complexes showed moderate activity compared to standard Fluconazole. Moreover, the anti-cancer activity of complexes (2–4) were examined against ovarian and breast cancer cells. Cell viability assays show that complexes (2–4) are promising anti-tumor in vitro.

1-Phenyl-1H-tetrazol-5-thiol (Hptt) has been used to prepare a series of inorganic and organometallic mercury(II) complexes. The prepared complexes were characterized by FTIR, 1H, 13C-{1H} NMR and CHN. The -COOH functionalized carbon nanotubes were used as co-organic nano ligands for preparation of a series of nano supported complexes. The resulted nano supported complexes were characterized by thermal analysis, FTIR, EDX and SEM. Results suggest that the MWCNTs-COOH is coordinated to mercury(II) through the oxygen atom of the carboxylic group in a monodentate fashion and the Hptt linked to mercury(II) through the sulfur atom of the thiolato group in a monodentate fashion. Moreover, after evaluation of their BET surface areas, the hydrogen storage capacities of the prepared nano supported complexes were studied. The measurements showed that the materials had a very high H2 storage capacity reached, 222 g/cm3 at 800 torr and 77 K.

Trans-[PdCl2(bzta)2] (bzta = 2-acetylaminobenzothiazole) (1a), trans-[PdCl2(bzmta)2] (bzmtaH = 2-acetylamino-6-methylbenzothiazole) (1b), trans-[PdCl2(bzcta)2] {bzcta = 2-acetylamino(6-chlorobenzothiazole)} (1c), cis-[PtCl2(bzta)2] (2a), cis-[PtCl2(bzmta)2] (2b) and cis-[PtCl2(bzcta)2] (2c) have synthesized and fully characterized; the molecular structures of 1b.dmf and 2a.2dmf reveal that the acetamide ligands are coordinated through the nitrogen atom of the heterocyclic ring. The anticancer effects of 1a and 2a-c were tested against a wide-range of cancer cell lines. All show cytotoxic activity, but are less effective than cis-platin. Unexpectedly, the palladium complex 1a was more active than the platinum complexes 2a-c, suggesting that future studies on related palladium complexes may be fruitful.

Six palladium (II) and platinum (II) mixed ligand complexes of metronidazole (mnz) and saccharinate (sac) or benzothiazolinolate (bit) complexes of the type [ML2(mnz)2], M = Pd or Pt, L = sac or bit, have been prepared in moderate to high yield. The newly prepared complexes have been characterized by elemental (C,H,N,S) analysis, conductivity measurements, infrared and 1H-NMR spectra. Characterization data showed that the mnz ligand in all of the prepared complexes is coordinated to metal center through the imidazole nitrogen atom. The (sac) anion ligand is coordinated through the endocyclic nitrogen atom, while the (bit) anion ligand is coordinated through the nitrogen atom in the palladium complex and through the oxygen atom of the carbonyl group in the platinum complexes. The geometry of the Pd (II) and Pt (II) complexes is square planar complexes. http://dx.doi.org/10.25130/tjps.24.2019.105

Reaction of Na2PdCl4 with two equivalents of N-hydroxymethylsaccharin (Sac-CH2OH) in the presence of NEt3 afforded trans-[Pd(κ2-Sac-CH2O)2]. Further reaction of [Pd(κ2-Sac-CH2O)2] with one equivalent of diphosphine (L2), Ph2P(CH2) n PPh2, (n = 1, dppm; 2, dppe and 3, dppp), Ph2P(S)(CH2)P(S)Ph2 (dppmS2) or Ph2P(O)(CH2)2P(O)Ph2 (dppeO2) afforded mixed ligand complexes [Pd(κ1-Sac-CH2O)2(L2)], while reaction with two equivalents of Ph3P, Ph3PO or Ph3PS (L) gave trans-[Pd(κ1-Sac-CH2O)2(L)2]. The N-hydroxymethylsaccharinate anion acts as a monodentate ligand, coordinating to the palladium center through the hydroxymethyl oxygen atom. The complexes were characterized by physico-chemical and spectroscopic methods. In addition, the free ligand N-hydroxymethylsaccharin and some of the complexes were screened in vitro for antibacterial activity.

Seven new complexes [Hg(k1-ptt)2](1), [Hg(k1-ptt)2(dppm)](2), [Hg(k1-ptt)2(dppe)](3), [Hg(k1-ptt)2(dppp)](4), [Hg(k1-ptt)2(dppb)](5), [Hg(k1-ptt)2(dppf)] (6), and [Hg(k1-ptt)2(PPh3)2] (7) have been synthesized and characterized. The reaction of two moles equivalent of 1-Phenyl-1H-tetrazole-5-thiol (Hptt) with one mole equivalent of Hg(oAc)2.xH2O in ethanol solution afford [Hg(k1-ptt)2] (1). Treatment of (1) with one mole equivalent of diphos (diphos : dppm, dppe, dppp, dppb, dppf) or two moles equivalent of PPh3 afforded a complexes of the types [Hg(k1-ptt)2(diphos)] (2-6) or [Hg(k1-ptt)2(PPh3)2] (7). The prepared complexes have been characterized by CHNS elemental analyses, molar conductivity, IR and NMR (1H, 13C and 31P) spectroscopy. In all complexes, the ptt- ligand is bonded through the sulfur atom of deprotonated thiol group, whereas the diphosphine ligands bonded as bidentate chelating and PPh3 bonded as a monodentate, to afford a tetrahedral geometry around the Hg+2 ion. http://dx.doi.org/10.25130/tjps.24.2019.083

A new complex of the type [Hg(k2-Saln)2] (1) was prepared from the reaction of mercury acetate and salicylanilide (HSaln) in (1:2) molar ratio EtOH as a solvent with presence an Et3N as a base. Treatment of complex (1) with diphosphine {where diphos: dppe, dppp, dppb dppf and dppmS2} in 1:1) (complex: diphos) molar ratio afforded a complexes of the types [Hg(k1-Saln)2(diphos)] (2-6),where as a complexes of the types [Hg(k1-Saln)2(phos)2] (7,8) when treatment of complex(1) with two moles of monophosphine (PPh3 or SPPh3). The prepared complexes were fully characterization by many technical such as elemental analysis, molar conductivity, infrared spectroscopy, and nuclear magnetic resonance (1H and 31P). In complex (1) the (Saln-) was bonded as bidentate chelating ligand through the oxygen atoms of the carbonyl and deprotonated hydroxyl group, whereas bonded as monodentate ligand through the oxygen atom of deprotonated hydroxyl group in all other complexes (2-8). The geometry of the complexes (1-8) is a tetrahedral around the mercury (II) ion. http://dx.doi.org/10.25130/tjps.24.2019.086

Addition of 2-aminobenzothiazole and substituted derivatives to mercuric acetate in warm ethanol leads to the high yield formation of [Hg{SC6H3XN(CN)}]n resulting from loss of hydrogen and sulfur-carbon bond cleavage. Addition of phosphines affords a series of complexes in which the new ortho-cyano-aminothiophenolate ligands adopt three different binding modes.

Different extracts of both fresh and dry leaves of Aloe eru A. Berger, A. vera L. Webb & Berth and A. arborescens Mill. were screened for their antifungal activity against Aspergillus niger, Cladosporium herbarum and Fusarium moniliforme. The toxicity of the isolated pure components were evaluated on the tested fungi. A comparative chromatographic study was performed to differentiate between natural components existing in various fractions and extracts of Aloe species and specific spray reagents were used for the detection of anthraquinones in the isolated components. Copyright © 1999 John Wiley & Sons, Ltd.

The synthesis of antimicrobial activity spirocompounds was achieved via the reaction of hydrazonoyl halides 1 with exocyclic 4-arylidene-2-methylimidazolin-5-one 3 in benzene in the presence of triethylamine. Correct elemental analyses and spectral data (IR, 1H NMR, 13C NMR and MS) confirm the structure of the synthesized spirocompounds. All the synthesized compounds were evaluated in vitro for their antimicrobial activity against five gram-positive and two gram-negative bacteria using well diffusion method in Mueller-Hinton agar. Most of them exhibited significant antibacterial activity compared with selected standard drugs.

X-ray transparent crystallization plates based upon a novel drop-pinning technology provide a flexible, simple and inexpensive approach to protein crystallization and screening. The plates consist of open cells sealed top and bottom by thin optically, UV and X-ray transparent films. The plates do not need wells or depressions to contain liquids. Instead, protein drops and reservoir solution are held in place by rings with micrometre dimensions that are patterned onto the bottom film. These rings strongly pin the liquid contact lines, thereby improving drop shape and position uniformity, and thus crystallization reproducibility, and simplifying automated image analysis of drop contents. The same rings effectively pin solutions containing salts, proteins, cryoprotectants, oils, alcohols and detergents. Strong pinning by rings allows the plates to be rotated without liquid mixing to 90° for X-ray data collection or to be inverted for hanging-drop crystallization. The plates have the standard SBS format and are compatible with standard liquid-handling robots.

Some new pyrazole-5-carbonitrile derivatives 8, 9 and pyrazole-5-carboxamide 13 were synthesized by the cycloaddition reaction of nitrilimines 3, 4 to α-cyanocinnamonitriles 5a-f and α-cyanocinnamamide 12a, b respectively. On the other hand 3, 4 add to ethyl α-cyanocinnamate 14a-f to give ethyl 2-pyrazoline-5-carboxylate derivatives 15, 16. Also, cycloaddition of 3, 4 to 3-cyanocoumarin 19a or 3-phenylsulphonylcoumarin 19b or 3-bromocoumarin 19c give chromeno[3,4-c]pyrazol-4(3H)-one derivatives 20. In the same direction, the cycloaddition of 3, 4 to 3-acetylcoumarin 22 and 3-benzoylcoumarin 23 gives the corresponding dihydrochromeno[3,4-] pyrazol-4(3H)-one 24 and 25 respectively. Oxidation of 24 and 25 give 20. Most of the prepared compounds showed good to moderate antibacterial and antifungal activities. Alguns novos derivados de pirazol-5-carbonitrila 8, 9 e pirazol-5-carboxamida 13 foram sintetizados pela reação de cicloadição de nitriliminas 3, 4 a α-cianocinamonitrilas 5a-f e α-cianocinamamida 12a, b, respectivamente. Por outro lado, a adição de 3, 4 a α-cianocinamato de etila 14a-f leva à produção de derivados de 2-pyrazoline-5-carboxilato de etila, 15, 16. Também, a cicloadição de 3, 4 à 3-cianocumarina 19a ou à 3-fenilsulfonilcumarina 19b ou à 3-bromocumarina 19c leva à produção de derivados do cromeno[3,4-c]pirazol-4(3H)-ona, 20. A cicloadição de 3, 4 à 3-acetilcumarina, 22 e 3-benzoilcumarina, 23, produz o correspondente diidrocromeno[3,4-c]pirazol-4(3H)-ona, 24 e 25, respectivamente. A oxidação de 24 e 25 produz 20. A maioria dos compostos preparados mostrou boa a moderada atividade antibacteriana e antifúngica.

A new micro method utilising charcoal chromatography has been developed for the determination of the individual basic amino-acids in protein hydrolysates. It is based on the fact that both the aromatic amino-acids and basic amino-acid picrates are strongly adsorbed by active-charcoal columns, and that the latter can be freed from the aromatic amino-acids by treatment of the adsorbent with aqueous ethyl acetate solution. The separation of the individual basic amino-acids depends on differential decomposition of their picrates on the columns by various eluents. The method can be used for the determination of histidine in the presence of other imidazole derivatives.