Yellow Crystals Research Articles

Structural, NBO, HOMO-LUMO Analysis Using DFT and Molecular Docking Analysis of Bioactive 3,4-Difluoroacetophenone-Thiosemicarbazone as a Potential Anticancer Agent

The thiosemicarbazone moiety serves as a structural template for the synthesis of a wide variety of N- and S-containing heterocyclic compounds which have proven in-vitro antitumor activity against A549 and MCF-7 cell lines and normal breast and lung cells. In this study, we have reported comprehensive theoretical studies using density functional theory (DFT) on molecular structure, molecular electrostatic potential (MEP), Natural Bond Analysis (NBO) and HOMO-LUMO analysis of an important thiosemicarbazone compound 3,4-difluoroacetophenone-thiosemicarbazone (DFAT). Pale yellow crystals were recently synthesized by mixing of 3,4-difluoroacetophenone and thiosemicabazide ethanolic solution and then crystallized by slow evaporation process. Anti-tumor activity of DFAT ligand was explained in terms of intra-molecular charge delocalization which gives insight into inter and intra-molecular interactions. Molecular docking studies of DFAT verified its inhibitory nature against 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1) (PDB ID: 3HB5) protein associated with cancer disease. From docking studies, it is found that the titled molecule exhibits a maximum binding affinity of −5.9[Formula: see text]kcal/mol with respect to the target protein. Three hydrogen bonds were formed with residues SER11 having the bond distances 3.00[Formula: see text]Å, 2.50[Formula: see text]Å and 2.34[Formula: see text]Å respectively. The DFAT molecule also shows hydrogen bonding with ASP65, THR190 and GLY15 residue with a bond distance 2.02[Formula: see text]Å, 2.05[Formula: see text]Å and 1.83[Formula: see text]Å respectively. A comparative study of the titled molecule with other several thiosemicarbazone derivatives shows that DFAT has good binding affinity than that of referenced drugs and can be used as a more potent active pharmaceutical ingredient (API) for cancer treatment.

Synthesis, crystal growth, electronic structures and optical properties of wide bandgap semiconductor (CH3NH3)2HgI4

The synthesis, crystal growth and electronic structures, as well as optical properties of Hg-based hybrid organic-inorganic compound (CH3NH3)2HgI4 are reported. Single crystal was grown through the anti-solvent method, yielding the faint yellow (CH3NH3)2HgI4 flake crystals. The structural analysis revealed that (CH3NH3)2HgI4 crystallized in the orthorhombic space group Pbca with a 0D crystal structure featuring anionic [HgI4]2- units that were surrounded by CH3NH3+ cations. Furthermore, (CH3NH3)2HgI4 does not decompose when being exposed to air, but the crystallinity slowly decays over time in air at room temperature. TGA and DSC show that it is stable for (CH3NH3)2HgI4 from room temperature to 223 °C. It shows that (CH3NH3)2HgI4 is a slightly indirect nature with 3.276 eV of band gap based on density functional theory calculations, which is close to 3.18 eV derived from UV–vis–NIR spectra of (CH3NH3)2HgI4 crystal. In addition, room temperature photoluminescence (PL) spectra of (CH3NH3)2HgI4 yields broad peaks at 540 nm with full width at half maximum (FWHM) values of 201 nm. These PL peaks are tentatively assigned to self-trapped excitons following the crystal and electronic structure considerations. The bands around the Fermi level have small dispersions, which is indicative of high charge localization with significant exciton binding energies in (CH3NH3)2HgI4. PL analysis indicates that (CH3NH3)2HgI4 may have potential research value as white-light-emitting phosphors and scintillator.

Synthesis of 3'-methoxy flavonol and its derivatives as potential inhibitors for Dengue NS2B/NS3 and molecular insight into binding interaction

Background: Infection with the Dengue virus can result in dengue fever (DD), which can progress to dengue hemorrhagic fever (DHF). Objective: In this work, molecule 3'-methoxy flavonol (3F) and its derivatives (T3F) were synthesized because they may be used to develop dengue antiviral DENV-2 NS2B/NS3 serine proteases. Method: Compound 2'-hydroxy-3-methoxy chalcone and hydrogen peroxide are used in the stirrer method to synthesize compound 3F with a yield of 33.24%, and yellow crystals of the 3F compound were produced. Results: The substance T3F was produced as white crystals with a yield of 69.42% by reacting compound 3F with ethyl chloroacetate using the reflux technique. Compound 3F exhibited absorption at maximal wavelengths of 212 nm, 244 nm, and 344 nm according to UV-Vis spectroscopy. UV-Vis spectroscopy of compound T3F revealed absorption at maximal wavelengths of 212 nm, 243 nm, and 320 nm. While a C=O ester group was replaced in the T3F synthesis step, the FT-IR spectroscopy of the 3F molecule revealed the existence of an OH group. Conclusion: Based on docking results, compound T3F has a binding free energy value that is extremely similar to that of panduratin A. Thus, it revealed that the T3F molecule has the potential to be an inhibitor of the NS2B/NS3 Protease virus DENV-2.

Lipid Peroxidation and Nitric Oxide Scavenging Activity of the tricin extracted from rice bran

Back ground: Rice bran is an industrial waste resulting from the grain milling process. Consisting of husk, aleurone, and fractions. It contains many nutrients, including soluble and insoluble fiber, vitamins, minerals, fats, proteins, and phytochemicals such as Ɣ-oryzanol, tocopherols, tocotrienols and tricin which has health-beneficial properties.
 Objective: The aim of research to estimate antioxidant activity of the aqueous extract of rice bran of the commercial jasmine variety and the tricin compound purified from it, by the method of nitric oxide suppression activity and the effectiveness of inhibiting lipid peroxidation, and the effect of the temperatures (63, 72,72, 85,100, 121,121, and 138) Co and the pH (4, 5, 6, 7, 8) in the activity.
 Materials and methods: Samples of rice bran of the commercial jasmine variety were collected from Al-Tahbeesh sites in Al-Najaf Al-Ashraf for the year (2021). The aqueous extract was prepared using the maceration in boiling distilled water with a temperature of 70 C°, and the crystals of tricin were isolated by using a silica gel column (60) and solvents recovery n-hexane, ethyl acetate and methanol, respectively. This process resulted in nine parts (A-I) of the ethyl acetate solvent, concentrated in a rotary evaporator and left in the refrigerator 48 hours with the addition of chloroform to it. Needle-shaped yellow crystals were obtained, which were used to estimate antioxidant activity. 
 Results: The effectiveness of purified tricin as an ability to inhibit nitric oxide was higher than that of the aqueous extract of rice bran and ascorbic acid at percentages of (97.82, 72.99 and 77.20)% respectively at a concentration of 400 µg / ml, the highest concentration used, also tricin was superior in inhibiting lipid peroxidation of 98.31% over the aqueous extract of rice bran of the commercial jasmine variety 81.28% and ascorbic acid 93.10 at the same concentration, purified tricin showed stability towards temperatures at times (30 min, 15 sec, 30 min, 1 min, 30 min, 5 min, 15 min and 2 sec) higher than that of the aqueous extract in both methods, as the effectiveness ratios of tricin by nitric oxide suppression method reached (64.25, 53.87, 42.78, 47.44, 38.48, 45.74 , 39.04 and 36.13)% respectively, and by the lipid peroxide suppression method (90.73, 85.06, 63.32, 77.50, 32.27, 76.65, 35.06 and 25.30) % respectively, the two methods of effectiveness were used to estimate the stability of the aqueous extract of rice bran and the tricin towards different pH. The effectiveness of tricin was higher than the aqueous extract of rice bran at all tested numbers, and the highest effectiveness of tricin at pH (pH7) with the method of inhibiting nitric oxide and inhibiting lipid peroxidation was (46.56 and 90.92)% respectively. 
 Conclusion: purified tricin higher antioxidant activity than the aqueous extract using both methods, and showed higher stability towards changes in temperature and during different time periods, and higher stability towards a change in pH, especially in neutral conditions compared to acidic conditions and basal.

New Minerals from the Redmond Mine, North Carolina, USA: II. Cubothioplumbite and Hexathioplumbite, Two New Minerals Containing the Cubane-Like [Pb4(OH)4]4+ Structural Unit

Abstract The new minerals cubothioplumbite (IMA2021-091) and hexathioplumbite (IMA2021-092), both with the ideal formula [Pb4(OH)4]Pb(S2O3)3, were found in the Redmond mine, Haywood County, North Carolina, USA, where they occur together in a highly unusual secondary assemblage that comprises a variety of rare Pb-Zn-Cu sulfates, thiosulfates, and carbonates. Cubothioplumbite has the following properties: yellow equant crystals to about 0.5 mm; white streak; adamantine luster; brittle; Mohs hardness 3; conchoidal fracture; no cleavage; 5.748 g/cm3 calculated density; isotropic with n > 2.00. Hexathioplumbite has the following properties: colorless hexagonal prisms to about 1 mm; white streak; adamantine luster; brittle; Mohs hardness 2½; curved fracture; no cleavage; 5.531 g/cm3 calculated density; uniaxial (−) with ω = 2.005(5) and ε = 1.995(5). Electron probe microanalyses provided the empirical formulae [Pb4(OH)4]Pb(S2O3)2.72(SO4)0.28 and [Pb4(OH)4]Pb(S2O3)2.68(SO4)0.32 for cubothioplumbite and hexathioplumbite, respectively. Cubothioplumbite is cubic, Pa, a = 14.9179(13) Å, V = 3319.9(9) Å3, and Z = 8. Hexathioplumbite is hexagonal, P63, a = 10.7213(10), c = 8.6541(6) Å, V = 861.49(17) Å3, and Z = 2. The structures of cubothioplumbite (R1 = 0.0354 for 1090 I > 2σI) and hexathioplumbite (R1 = 0.0791 for 1062 I > 2σI) both contain cubane-like [Pb4(OH)4]4+ structural units.

Annealed titanium dioxide nanomaterials for rapid hydrogen production and Rhodamine-B degradation

Hydrogen energy methods with effective catalysts create clean, sustainable energy. Nanomaterials impact several fields. This study implies about rapid manufacture of Nano photocatalyst materials for hydrogen production and wastewater treatment, including Rhodamine-B dye removal. The TiO2, plasma chemical reactor with segmented arc design synthesizes photocatalyst nanomaterial quickly. 10 ltr/min oxygen flow yielded the best powder. TiO2 nanoparticles were blue due to non-stoichiometric manufacturing, however annealing created yellow crystals with no huge agglomerated particles and finer grain size. XRD, TEM, SAED, FESEM, and XPS demonstrated that the photocatalyst Nanomaterials could remove Rhodamine-B dye from wastewater. The modified dye solution had 80% lower COD. Annealed titanium dioxide nanomaterial is ideal for wastewater treatment due to its two-step synthesis, colour degradation, and antibacterial capabilities. In acidic solution, annealed yellow and blue nanoparticle specimens were tested for HER catalysis. The blue sample's Tafel slope (231 mV/decade) was much worse than the annealed sample's 68 mV/decade.

Scissor-like Au4Cu2 Cluster with Phosphorescent Mechanochromism and Thermochromism

Reaction of [Au(tht)2](ClO4) (tht = tetrahydrothiophene), [Cu(CH3CN)4](ClO4), 3,6-di-tert-butyl-1,8-diethynyl-9H-carbazole (H3decz), and bis(2-diphenylphosphinophenyl)ether (POP) in the presence of triethylamine (NEt3) gave the cluster complex Au4Cu2(decz)2(POP)2 as yellow crystals. As revealed by X-ray crystallography, the Au4Cu2 cluster exhibits scissor-like structure sustained by two decz and two POP ligands and stabilized by Au-Cu and Au-Au interactions. The Au4Cu2 cluster shows bright yellow to orange photoluminescence upon irradiation at >300 nm, arising from 3[π (decz)→5d (Au)] 3LMCT (ligand-to-metal charge transfer) and 3[π→π* (decz)] 3IL (intraligand) triplet states as revealed by theoretical and computational studies. When it is mechanically ground, reversible phosphorescence conversion from yellow to red is observed owing to more compact molecular packing and thus stronger intermetallic interaction. Variable-temperature luminescence studies reveal that it displays distinct red-shifts of the emission whether the temperature is elevated or lowered from ambient temperature, suggestive of exceptional thermochromic phosphorescence characteristics.

Xanthoangelol, geranilated chalcone compound, isolation from pudau leaves (Artocarpus kemando Miq.) as antibacterial and anticancer

Abstract From the leaves of Artocarpus kemando Miq, locally known as pudau plant, a flavonoid has been isolated and identified. The compound was then tested as antibacterial agent against Bacillus subtillis and Escherichia coli. The first step of isolation was extraction by maceration using methanol as solvent, and then followed by fractionation using partition treatment and vacuum liquid chromatography. Finally, the compound was purified using column chromatography method. The purity of the compound was evaluated using thin layer chromatography and melting point measurement, and the compound was subsequently characterized using UV–Vis, IR, and NMR spectroscopy. A total of 66.2 mg of the compound was obtained, in the form of yellow needle crystals with a melting point of 142.8–144 °C, which is a compound of geranylated chalcone, xanthoangelol. Xanthoangelol was the first chalcone compound isolated from A. kemando. Antibacterial tests were carried out at varied doses of 0.5; 0.4; and 0.3 mg/disk, and revealed that the compound exhibits high inhibitory power against B. subtillis, but has no activity against E. coli. The anticancer activity of xanthoangelol on MCF-7 cells indicated that the compound has an IC50 value of 7.79 μg/mL, suggesting that the compound possesses an active cytotoxic activity.

Isolation of AM Fungi from Rhizospheric Soil and Assessing Their Potential in Revegetating the Mining Wasteland of Gujarat using Inoculated Trees Saplings

Fluorspar (CaF2), is a common mineral, occurring in green, purple, yellow, or colorless crystals, which is used in metallurgy and makinga variety of chemicals used in refrigeration. Kadipani in Gujarat has large deposits of this ore. Open cast mining by GMDC has resultedin disturbed ecology. Earlier the efforts have been made by the forest department to grow tree species, in order to restore the forestecosystem, but the plants grew slowly and with stunted morphology and scanty survival. The obligate fungal symbionts known asarbuscular mycorrhizal fungi (AMF) present in plants play a key factor supporting plant growth in stressed conditions. Therefore, AMFstrains were first isolated from mining area and were used to raise the saplings first in polybags. Then after 75 days these were used forrevegetating the mine burdens or nearby waste land. The paper presents a pioneering efforts made to isolate and identify, the AMFfrom Fluorspar mines in Gujarat and then Glomus fasciculatum was incorporated in polybags filled with normal garden soil. Plants werealso raised by single spore inoculation method. Preliminary experiments revealed that the inoculated AMF strains promoted seedlinggrowth of Leuceana leucocephala and Millettia pinnata. The inoculation of AMF spores enhanced the growth of both the plants, and suchapplication can be used in sustainable restoration of the mining areas. Review discusses the structure of AM spores and mechanismsinvolved to equip them to survive in stressed situations and as symbionts help the plants to perform better.

Luminescent Anionic Cyclometalated Organoplatinum (II) Complexes with Terminal and Bridging Cyanide Ligand: Structural and Photophysical Properties

We present the synthesis and characterization of two series of mononuclear heteroleptic anionic cycloplatinated(II) complexes featuring terminal cyanide ligand Q+[Pt(C^N)(p-MeC6H4)(CN)]- [C^N = benzoquinolate (bzq), Q+ = K+ 1 and NBu4+ 4; 2-phenylpyridinate (ppy), Q+ = K+ 2 and NBu4+ 5 and 2-(2,4- difluorophenyl)pyridinate (dfppy), Q+ = K+ 3 and NBu4+ 6] and a series of symmetrical binuclear complexes (NBu4)[Pt2(C^N)2(p-MeC6H4)2(μ-CN)] (C^N = bzq 7, ppy 8, dfppy 9). Compounds 5, 6, and 7-9 were further determined by single-crystal X-ray diffraction. There are no apparent intermolecular Pt···Pt interactions owing to the presence of bulky NBu4+ counterion. Slow crystallization of K[Pt(ppy)(p-MeC6H4)(CN)] 2 in acetone/hexane evolves with formation of yellow crystals, which were identified by single-crystal X-ray diffraction methods as the salt complex {[Pt(ppy)(p-MeC6H4)(CN)]2K3(OCMe2)4(μ-OCMe2)2}[Pt(ppy)(p-MeC6H4)(μ-CN)Pt(ppy)(p-MeC6H4)]·2acetone (10), featuring the binuclear anionic unit 8- neutralized by an hybrid inorganic-organometallic coordination polymer {[Pt(ppy)(p-MeC6H4)(CN)]2K3(OCMe2)4(μ-OCMe2)2}+. The photophysical properties of all compounds were recorded in powder, polystyrene film, and solution states with a quantum yield up to 21% for 9 in the solid state. All complexes displayed bright emission in rigid media, and for the interpretation of their absorption and emission properties, density functional theory (DFT) and time-dependent DFT calculations were applied.

Structural diversity of copper(I)-ethylene complexes with 2,4-bis(2-pyridyl)pyrimidine directed by anions.

The 3 : 1 reaction of [Cu(C2H4)n]ClO4 with 2,4-bis(2-pyridyl)pyrimidine (bpprd) in Me2CO under C2H4 afforded yellow prism crystals of the dinuclear Cu(I)-C2H4 complex [Cu2(bpprd)(η2-C2H4)2(ClO4)2] (1). The 3 : 1 reaction of [Cu(C2H4)n]NO3 with bpprd in Me2CO under C2H4 afforded yellow plate crystals of the tetranuclear Cu(I)-C2H4 complex [Cu4(bpprd)2(η2-C2H4)4(μ-NO3)2](NO3)2 (2). The 10 : 1 reaction of [Cu(C2H4)n]BF4 with bpprd in Me2CO under C2H4 afforded yellow plate crystals of the dinuclear Cu(I)-C2H4 complex [Cu2(bpprd)(η2-C2H4)2(BF4)]BF4 (3). The 3 : 1 reaction of [Cu(C2H4)n]BF4 with bpprd in Me2CO under C2H4 afforded red prism crystals of the polymeric Cu(I)-C2H4 complex {[Cu6(bpprd)4(η2-C2H4)2(μ-η2:η2-C2H4)(μ-BF4)2](BF4)4}n (4). The X-ray crystal structures of complexes 1-4 have been determined. The structural diversity of Cu(I)-C2H4 complexes bridged by bpprd with different anions was demonstrated. The 1D Cu(I)-bpprd/C2H4 coordination polymer 4 bridged by unusual μ-η2:η2-C2H4 and the μ-BF4- anion is of particular significance. Complex 1 exhibited relatively well-resolved 1H NMR signals of bpprd and C2H4 (δ = 4.97 ppm) in (CD3)2CO at 23 °C.

Effect of Gel Electrolyte, Paste and Electrode on the Efficiency of Dye-Sensitized Solar Cell using Schiff Base Dye Compound

The low cost and ease of production have led to widespread adoption of dye-sensitized solar cells (DSSCs). Therefore, this study aims to synthesize Schiff base compounds from salicylaldehyde and ethylenediamine as a sensitizer in DSSC. The Shiff base compound was synthesized using the condensation method with mol ratio of 1:1 and the results showed yellow crystals with a yield of 81.14%. Furthermore, the UV-Vis spectrometer analysis showed that the Schiff base compound has bathochromic shift with a maximum wavelength change from 324 and 328 nm to 335 nm with transition n→π, while the IR spectrum at wavenumber of 1610 cm-1 indicated the presence of an azomethine group (–C=N–). The TG-DTA analysis showed a mass loss stage of the Schiff base molecule at 97.2% in the temperature range of 180-300 ºC. Based on UV-Vis, IR and TG-DTA data, the synthesized Schiff base has the potential to be used as a sensitizer in DSSC. The fabrication was then carried out using two variations of semiconductor namely TiO2 and ZnO, three variations of PEG gel electrolyte with 0.05 M, 0.1 M and 0.15 M, as well as three counter electrodes including graphite from a pencil, candle flame and a combination of both. Based on the results, DSSC based on TiO2 semiconductor with 0.15 M PEG gel electrolyte and candle flame counter electrode produced the highest efficiency of 0.29 % with maximum voltage (Vmax) of 370 mV and maximum current strength (Imax) of 0.8 mA.

Green Synthetic Methods for a Schiff Base from 2-Aminopyridine and 4-Ethoxybenzaldehyde

The novel Schiff base was acquired from the reaction between 2-aminopyridine and 4-ethoxybenzaldehyde using three (3) techniques; refluxing in ethanol for 2 hours, stirring in ethanol and an ethanol-water (1:1) mixture at room temperature for an hour. The synthesis of the 2-aminopyridine-4-ethoxybenzaldehyde Schiff base produced dark yellow crystals with melting point range of 95-97oC. The reaction in ethanol under reflux produced the highest yield of 88.2% while the reaction in ethanol and ethanol-water (1:1 v/v) mixture at room temperature gave 69.2% and 43.5% yield of the compound respectively. The IR spectrum showed the following bands; 1681cm-1 (C=N), 1595cm-1 (aromatic C=C stretch), 2981cm-1 (aromatic C-H stretch), 1509cm-1 (aromatic C=N stretch), 1155cm-1 (aliphatic C-C stretch), 1036 (aromatic C-O stretch), 2825 (aliphatic C-H stretch). The 13C NMR spectrum showed the following chemical shifts (δppm); 158.48 (C=N, imino), 154.98 and 150.18 (C-N of aromatic pyridine moiety), 121.44 – 137.53 (aromatic carbons), 158.68 (aromatic C-O), 63.88 (aliphatic C-O), 15.22 (aliphatic C). The 1H NMR spectral data (δppm) for the compound gave the following results; 7.06-7.91, m (8H) (Ar-H), 9.71, s (1H) (HC=N-), 4.10, q (2H) and 1.32, t (3H) (OCH2CH3). The spectral data was in agreement to the predicted structure of the Schiff base.

A Cationic Barium Hydride Complex Supported by an NNNN‐Type Macrocycle

AbstractThe dibenzyl complex of barium [(Me4TACD)Ba(CH2Ph)2] was prepared by reacting [Ba(CH2Ph)2] with NNNN‐type macrocycle Me4TACD (Me4TACD=1,4,7,10‐tetramethyltetraazacyclododecane) and isolated as yellow crystals. Single crystal X‐ray diffraction revealed η2‐ and η3‐coordination of the benzyl groups. The benzylbarium cation in [(Me4TACD)Ba(CH2Ph)(thf)][B(C6H3‐3,5‐Me2)4] was obtained upon protonolysis of the neutral bariumdibenzyl with the weak Brønsted acid [NEt3H][B(C6H3‐3,5‐Me2)4] and isolated as colorless crystals. When the benzylbarium cation was reacted with H2 (1 bar) in THF at room temperature, colorless crystals of the dinuclear hydride complex [(Me4TACD)2Ba2(μ‐H)2(thf)4][B(C6H3‐3,5‐Me2)4]2 precipitated from the reaction mixture and characterized by single crystal X‐ray diffraction. The structural motif [Ba2(μ‐H)2]2+ was compared with that published in the literature. Hydrogenolysis of the dibenzyl [(Me4TACD)Ca(CH2Ph)2] under the same conditions resulted in decomposition.

Potential antioxidants of secondary metabolite isolates ethyl acetate fraction Coleus amboinicus Lour. Leaves.

The aim of the study was to isolate and characterize secondary metabolites that have the potential as antioxidants from the ethyl acetate fraction of the leaves of Coleus amboinicus, L. (C. amboinicus).
 Materials and methods. Purification of the ethyl acetate fraction of C. amboinicus using gravity column chromatography with a stationary phase (silica gel, Merck) and a mobile phase with a solvent ratio of n-hexane (Merck) and ethyl acetate (Merck). Examining isolates includes physical (colour, shape, and melting point). Qualitative purity detection by TLC at 254 nm and 366 nm wavelengths. Structural analysis of metabolites with UV-Vis spectrometer (Spectronic 3000, Genesis 10, Japan), FT-IR(KBr) (Shimadzu IR Prestige-21, Japan), NMR spectrometer (JEOL spectrometer, Japan) operating at 500 MHz (1H-NMR) and 125 MHz (13C-NMR), and Shimadzu's GC-MS (QP-2010S Shimadzu, Japan) and determination of potential antioxidant activity using the DPPH method.
 Results. The secondary metabolite compounds were isolated in the form of yellow crystals with a melting point of 232-233 °C and Rf values of 0.86 and 0.56, which TLC monitored at a solvent ratio of n-hexane and ethyl acetate 6:4 and 8:2. Spectronic analysis with a UV-Vis Spectrometer showed two electron absorbances, namely a wavelength of 210 nm indicating methanol solvent and 272 nm isolate. The absorbance of functional groups at wave numbers 3379 cm-1 (-OH; hydroxy), 2931 cm-1 (-CH; aliphatic), 1735 cm-1 (-C=O; carbonyl ketone), 1234 cm-1 (-CO-; methoxy) and 1643 cm-1 (-C=C-; alkene). GC-MS analysis obtained two absorbance peaks, (1) the first retention time of 6.658 minutes (3.95 %) and (2) the second retention time of 9.001 minutes (96.05 %). Structural analysis with 1H&13C-NMR showed 28 types of protons and 22 types of carbon. The antioxidant activity potential test showed an activity value (IC50) of 338.54 ppm.
 Conclusion. The structure of the isolated secondary metabolite compound is 16-acetoxy-7α-hydroxyroyleanone (syn. 16-acetoxyhorminone) and has the potential as an antioxidant.

Chemical Evolution in Solutions of Ir Complex [H(dmso) 2 ] 2 [IrCl 6 ]. Structures of [H(dmso) 2 ] 2 [IrCl 6 ], [H(dmso)][IrCl 4 (dmso) 2 ], [Me 2 SCH 2 C(O)Me][IrCl 4 (dmso) 2 ], [Me 2 SCH 2 C(O)Me] 2 [IrCl 6 ] and Its Os Analogue

According to our solution reactivity studies, the reactant [H(dmso)2]2[IrCl6] undergoes slow spontaneous reduction of Ir(IV) to Ir(III) in all solvents under study, including water, hydrochloric acid, and acetone. A concurrent reaction is realized in acetone solutions, which effectively gives rise to the incorporation of DMSO into the iridium coordination sphere to afford trans-[IrIIICl4(dmso)2]−. The chemical evolution of [H(dmso)2]2[IrCl6] extends beyond the iridium-centered complex anion.

Synthesis and Complexation Study of New Aminoalkynyl−amidinate Ligands

AbstractThe current library of amidinate ligands has been extended by the synthesis of two novel dimethylamino‐substituted alkynylamidinate anions of the composition [Me2N−CH2−C≡C−C(NR)2]−(R =iPr, cyclohexyl (Cy)). The unsolvated lithium derivatives Li[Me2N−CH2−C≡C−C(NR)2] (1: R =iPr,2: R = Cy) were obtained in good yields by treatment ofin situ‐prepared Me2N−CH2−C≡C−Li with the respective carbodiimides, R−N=C=N−R. Recrystallization of1and2from THF afforded the crystalline THF adducts Li[Me2N−CH2−C≡C−C(NR)2] ⋅ nTHF (1 a: R =iPr,n=1;2 a: R = Cy,n=1.5). Precursor2was subsequently used to study initial complexation reactions with selected di‐ and trivalent transition metals. The dark red homoleptic vanadium(III) tris(alkynylamidinate) complex V[Me2N−CH2−C≡C−C(NCy)2]3(3) was prepared by reaction of VCl3(THF)3with 3 equiv. of2(75 % yield). A salt‐metathesis reaction of2with anhydrous FeCl2in a molar ratio of 2 : 1 afforded the dinuclear homoleptic iron(II) alkynylamidinate complex Fe2[Me2N−CH2−C≡C−C(NCy)2]4(4) in 69 % isolated yield. Similarly, treatment of Mo2(OAc)4with 3 or 4 equiv. of2provided the dinuclear, heteroleptic molybdenum(II) amidinate complex Mo2(OAc)[Me2N−CH2−C≡C−C(NCy)2]3(5; yellow crystals, 50 % isolated yield). The cyclohexyl‐substituted title compounds2 a,4, and5were structurally characterized through single‐crystal X‐ray diffraction studies.

Synthesis and characterization of Phenyl bis- hydrazone complexes with Pd (II), Mn (II), Ni (II) and Fe(III) ions

A new ligand of phenyl bis-hydrazone (V) was been synthesized as a result of a reaction between phenyl-isatin hydrazone and salicyladehyde. The yellow crystals of (V) was been studied using IR, 1H.n.m.r 13C-n.m.r, UV-Vis spectrum and molar conductivity measurements. The complexes of Palladium (II), Nickel (II), Manganese (II) and Iron (III) with phenyl bis-hydrazone have been synthesized and characterized on based on molar conductivity, magnetic susceptibility data, UV-Vis and IR spectral studies. The spectral data referred to that the ligand acts as monobasis tridentate, coordinating through phenolate oxygen, azomethine nitrogen, and carbonyl oxygen of isatin moiety. On the basis on the above results an octahedral geometry has been proposed for the mentioned complexes.

Tandem production of high-purity sodium glycolate via the dual purification technology of crystallization and active carbon adsorption

High-purity glycolic acid (GA) are highly required for the production of biodegradable polymers, pharmaceuticals, and fine chemicals. For production of bio-polyester, GA purity has emerged as a bottleneck. In this paper, we innovatively propose crystallization to dispose of purity problem and investigated the repurification of sodium glycolate crystals. Compared to traditional chemical techniques, resting cell catalysis with bio-oxidation of ethylene glycol (EG) is a promising method for the green industrial production of GA. Gluconobacter oxydans is one of the most promising strains because of its ability to ferment high GA titer from EG. However, the GA directly from fermentation broth does not meet the high purity requirements for biodegradable materials. Therefore, a tandem process was designed and experimentally verified by combining crystallization and active carbon (AC) adsorption. Sodium glycolate (SG) formation was adopted due to low-cost operation in the biological step and easy electrodialysis of GA. According to the dissociation constants (Kɑ) of glycolate, the fermentation broth was adjusted to pH 9.50 and SG saturates at 60 ℃ for SG crystallization. The macroscopic yellow plate-like crystals 91.1 g of SG with 94 % purity were produced at room temperature (25℃). In the tandem process, AC rapidly removed most pigment-like contaminants in the fermentation broth but adsorbed only a little SG (1 %), indicating selective and effective adsorption. Over 97 % of the color was removed by adding 8 % AC to a saturated solution (188 g/L). Finally, 79.2 g SG with 99 % purity was obtained at the yield of 87 % from 104 g/L SG broth. This tandem process could provide an economically-feasible approach for the industrial bioproduction of high-purity SG and GA derived from EG.

Matthiasweilite, PbTe4+O3, a New Tellurite Mineral from the Delamar Mine, Lincoln County, Nevada, USA

ABSTRACT Matthiasweilite (IMA2021-069), Pb2+Te4+O3, is a new mineral discovered at the Delamar mine, Lincoln County, Nevada, USA. It is a secondary mineral, associated with adanite, choloalite, northstarite, and other oxysalts in a quartz-rich matrix, that developed in an altered primary ore along with altaite, tetrahedrite-(Zn), native gold, and other sulfides and selenides. The mineral occurs as tightly intergrown masses of light yellow crystals. The streak is white, luster is adamantine, Mohs hardness is 2½, tenacity is brittle, and fracture is conchoidal; no obvious cleavage is present. The calculated density is 7.282 g/cm3 for the empirical formula. Data from electron probe microanalysis and assuming O = 3 gives the empirical formula Pb0.99Te4+1.01O3. Matthiasweilite is triclinic, space group P, with cell parameters a = 7.0256(4), b = 10.6345(6), c = 11.9965(8) Å, α = 78.513(6), β = 83.104(6), γ = 84.083(6)°, V = 869.10(9) Å3, and Z = 10. The crystal structure (R1 = 0.0523 for 3416 I > 2σI reflections) consists of Te4+O3 trigonal pyramids that are linked via relatively short (<2.6 Å) Pb–O bonds to form a framework.