A novel magnetite C18/paracetamol/alginate adsorbent bead for simultaneous extraction of synthetic antioxidants and bisphenol A in water samples.

A novel magnetic composite bead was synthesized using carbon 18, paracetamol and alginate (mC18/Pa/Alg). The bead was applied to simultaneously adsorb butylated hydroxytoluene, butylated hydroxyanisole, and bisphenol A from water samples by magnetic solid-phase extraction (MSPE). The adsorbed analytes were determined by gas chromatography-flame ionization detection. The morphology and composition of the bead were examined by field emission scanning electron microscopy, energy-dispersive X-ray spectrometry, X-ray diffraction analysis, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller surface analysis. The best condition of MSPE included an adsorbent bead made with 0.8% sodium alginate, a 0.3 g adsorbent dose, a sample solution pH of 7, and a desorption time of 20 min in methanol. The proposed method exhibited linearity at concentrations between 0.015 and 1.00 µg mL-1 of analytes. Limits of detection ranged from 6.86 to 9.66 ng mL-1. Recoveries from 80.3 to 100.1% were achieved with interday and intraday precisions (RSDs) of 0.4-4.3%.

Short Total Synthesis of (+)-Colletotryptins B-D and Mucronatin B Derivative.

The short and first total synthesis of (+)-colletotryptins B-D, ent-colletotryptin A, and diastereomer of mucronatin B, which are a group of natural 3-(indol-2-yl)-3-(indol-3-yl)-1,2-propanediol (IIPDO) analogues containing two stereogenic centers at the C8' and C9' positions, isolated from endophytic fungus Colletotrichum sp. SC1355 and Tetrapterys mucronata, respectively, has been successfully accomplished in two and three steps with overall yields ranging from 28 to 54%. Key features of this synthesis include an innovative Bi(OTf)3-catalyzed stereoselective transindolylation of (S)-3,3'-di(1H-indol-3-yl)propane-1,2-diol. The operational simplicity, environmentally friendly catalyst, and broad functional group tolerance of this modular strategy render it suitable for adoption in both academic and industrial settings.

Diastereoselective Addition of PhSCF2SiMe3 to Chiral N-tert-Butanesulfinyl Ketimines Derived from Isatins: Synthesis of Enantioenriched gem-Difluoromethylenated Spiro-pyrrolidinyl and Spiro-piperidinyl Oxindoles.

A convenient and efficient synthetic strategy to prepare enantioenriched gem-difluoromethylenated spiro-pyrrolidinyl and spiro-piperidinyl oxindoles is described. Fluoride-mediated diastereoselective nucleophilic addition of PhSCF2SiMe3 to chiral N-tert-butanesulfinyl ketimines derived from isatins was a key step and provided diastereomeric adducts, which were readily separable. Removal of the chiral sulfinyl group followed by structural manipulation afforded chiral gem-difluoromethylenated spiro-pyrrolidinyl and spiro-piperidinyl oxindoles.

Syntheses, crystal structures and Hirshfeld surface analyses of bis-(2-mercaptobenzimidazole)-bromo- and iodo-copper(I) complexes.

The title complexes, bromidobis(2,3-dihydro-1H-1,3-benzodiazole-2-thi-one)copper(I), [CuBr(C7H6N2S)2] (1), and bis(2,3-dihydro-1H-1,3-benzodiazole-2-thione)iodidocopper(I) acetone monosolvate, [CuI(C7H6N2S)2]·CH3COCH3 (2), were prepared by the reaction of copper(I) bromide/iodide with 2-mercaptobenzimidazole. Both complexes have mononuclear structures with the copper atom coordinated by two 2-mercaptobenzimidazole mol-ecules via their S atoms and one halide atom in an approximate trigonal-planar arrangement. In their extended structures, N-H⋯S hydrogen bonds and π-π contacts are found in both complexes; as a result of the acetone solvent mol-ecule in (2), N-H⋯O contacts are also observed. Hirshfeld surface analyses were carried out to aid in the visualization of these inter-actions, which showed that H⋯H contacts contribute 34.6% for (1) and 34.1% for (2) to the overall surface, followed by contributions from H⋯S/S⋯H, H⋯C/C⋯H and C⋯C contacts, respectively. As expected, H⋯O/O⋯H contacts are observed only in (2). The IR and 1H and 13C NMR spectra of (1) and (2) are described.

Phloroglucinol-meroterpenoids from the leaves of Eucalyptus camaldulensis Dehnh.

Fourteen undescribed phloroglucinol-meroterpenoids, namely eucalypcamals A-N, were isolated from a CH2Cl2 extract of the leaves of Eucalyptus camaldulensis Dehnh. In addition, from the same extract, twelve known phloroglucinols, three known flavonoids, and four known phenolic compounds were also isolated. The structures of the undescribed compounds were analyzed by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, and high resolution electrospray ionization mass spectrometry (HRESIMS). The assignments of the absolute configurations were performed by comparing the experimental electronic circular dichroism (ECD) data with the calculated values. Eucalyprobusal E was found to be cytotoxic against HCT116, Jurkat, and MDA-MB-231 cell lines with IC50 values of 17.6, 9.44, and 17.9 µM, respectively. Eucalrobusone F exhibited antibacterial activity against methicillin-resistant S. aureus (MRSA) and S. aureus with minimum inhibitory concentration/minimum bactericidal concentration (MIC/MBC) values of 4/4 µg/mL while euglobal Ia1 showed antifungal activity with MIC/MFC values of 16/16 µg/mL.

2-Oxaspiro[4.5]decane and α-pyrenocine derivatives from the endophytic fungus Roussoella sp. PSU-H51.

One new 2-oxaspiro[4.5]decane, roussoellide, and one new α-pyrenocine, 2',3'-dihydropyrenocine A, together with nine known compounds including known arthropsolide A, and pyrenocines A and E, were obtained from the culture broth of the endophytic fungus Roussoella sp. Their structures were determined using spectroscopic data. The absolute configuration of known arthropsolide A was assigned on the basis of X-ray diffraction data using Cu Kα radiation. Known pyrenocine A displayed weak cytotoxic activity against breast cancer (MCF-7) cells with an IC50 value of 27.1 µM and weak antifungal activity against Microsporum gypseum SH-MU-4 with an MIC value of 615.2 µM.[Formula: see text].

Synthesis, crystal structure and Hirshfeld surface analysis of [bis-(di-phenyl-phosphan-yl)methane-κP]chloridobis-[2-(pyridin-2-yl)phenyl-κ2 N,C 1]iridium(III).

The title IrIII complex, [Ir(C11H8N)2Cl(C25H22P2)], was synthesized from the substitution reaction between the (ppy)2Ir(µ-Cl)2Ir(ppy)2 (ppy = deprotonated 2-phenyl-pyridine, C11H8N-) dimer and 1,1-bis-(di-phenyl-phosphan-yl)methane (dppm, C25H22P2) under an argon gas atmosphere for 20 h. The IrIII atom is coordinated by two C,N-bidentate ppy anions, a unidentate dppm ligand and a chloride anion in a distorted octa-hedral IrC2N2PCl arrangement. The N donor atoms of the ppy ligands are mutually trans while the C atoms are cis. Intra-molecular aromatic π-π stacking between the phenyl rings of ppy and dppm, and C-H⋯Cl inter-actions are observed. In the crystal, C-H⋯Cl and C-H⋯π contacts link the mol-ecules into a three-dimensional network. A Hirshfeld surface analysis was carried out to further qu-antify the inter-molecular inter-actions, and indicated that H⋯H contacts (63.9%) dominate the packing.

Syntheses and crystal structures of hydrated and anhydrous 1:2 cocrystals of oxyresveratrol and zwitterionic proline.

The hydrated and anhydrous 1:2 cocrystals of oxyresveratrol (4-[(E)-2-(3,5-di-hydroxy-phen-yl)ethen-yl]benzene-1,3-diol; OXY; C14H12O4) and proline [(S)-pyrrolidine-2-carb-oxy-lic acid; PRO; C5H9NO2], namely, 4-[(E)-2-(3,5-di-hydroxy-phen-yl)ethen-yl]benzene-1,3-diol bis-[(S)-pyrrolidin-1-ium-2-carboxyl-ate] monohydrate, C14H12O4·2C5H9NO2·H2O, and the anhydrous form, C14H12O4·2C5H9NO2, were obtained by crystallization at different temperatures. Both of them crystallize with ortho-rhom-bic (P212121) symmetry. The structures display N-H⋯O and O-H⋯O hydrogen-bonding inter-actions between PRO and PRO, OXY and OXY, and OXY and PRO. In the hydrated cocrystal, these types of contacts are also observed between the OXY, PRO and water mol-ecules. A combination of these inter-actions leads to a three-dimensional supra-molecular assembly in each case. Hirshfeld surfaces were used to gain further insight into the inter-molecular inter-actions in the packing, including the relative percentage contributions of the significant inter-molecular H⋯H and H⋯O/O⋯H contacts.

Crystal and mol-ecular structures of a binuclear mixed ligand complex of silver(I) with thio-cyanate and 1H-1,2,4-triazole-5(4H)-thione.

The complete mol-ecule of the binuclear title complex, bis-[µ-1H-1,2,4-triazole-5(4H)-thione-κ2 S:S]bis-{(thio-cyanato-κS)[1H-1,2,4-triazole-5(4H)-thione-κS]silver(I)}, [Ag2(SCN)2(C2H3N3S)4], is generated by crystallographic inversion symmetry. The independent triazole-3-thione ligands employ the exocyclic-S atoms exclusively in coordination. One acts as a terminal S-ligand and the other in a bidentate (µ2) bridging mode to provide a link between two AgI centres. Each AgI atom is also coordinated by a terminal S-bound thio-cyanate ligand, resulting in a distorted AgS4 tetra-hedral coordination geometry. An intra-molecular N-H⋯S(thio-cyanate) hydrogen bond is noted. In the crystal, amine-N-H⋯S(thione), N-H⋯N(triazol-yl) and N-H⋯N(thio-cyanate) hydrogen bonds give rise to a three-dimensional architecture. The packing is consolidated by triazolyl-C-H⋯S(thio-cyanate), triazolyl-C-H⋯N(thiocyanate) and S⋯S [3.2463 (9) Å] inter-actions as well as face-to-face π-π stacking between the independent triazolyl rings [inter-centroid separation = 3.4444 (15) Å]. An analysis of the calculated Hirshfeld surfaces shows the three major contributors are due to N⋯H/H⋯N, S⋯H/H⋯S and C⋯H/H⋯C contacts, at 35.8, 19.4 and 12.7%, respectively; H⋯H contacts contribute only 7.6% to the overall surface.

Anti-HIV-1 activities of constituents from the rhizomes of Boesenbergia thorelii.

A new lignan, thoreliin A (1), and a new bisnorlignan, thoreliin B (2), were isolated from a MeOH extract of the rhizomes of Boesenbergia thorelii. In addition, the known bisnorlignans 3 and 4, neolignan 5, phenylpropanoids 6-15, as well as benzenoids 18-21 were also obtained from the same source. The structures were elucidated based on their spectroscopic data. By single crystal X-ray analysis, the relative stereochemistry of 1 was confirmed. All isolated compounds were evaluated for anti-HIV-1 activities. Among them, thoreliin A (1) exhibited anti-HIV-1 activities on both HIV-1 reverse transcriptase (41.43% inhibition at 200 µg/mL) and syncytium reduction assays (EC50 20.6 µM, SI 3.7), while compounds 3-6, 9 and 11-21 showed anti-HIV-1 activity only in the anti-syncytium assay (EC50 6.6-454.1 µM, SI >1.32-7.75).

Trichothecenes from a Soil-Derived Trichoderma brevicompactum.

Six new (1-6), together with seven known (7-13), trichothecenes were isolated from the soil-derived Trichoderma brevicompactum PSU-RSPG27. Their structures were established using spectroscopic data. The structure of 1 was confirmed by X-ray data. Trichodermin (7) exhibited the most potent activity against Plasmodium falciparum (K1 strain) with an IC50 value of 0.1 µM, while other trichothecenes (1, 8, 9, and 12) were much less active, with IC50 values in the range of 7.1-9.6 µM. Compound 7 displayed activity against noncancerous Vero cells with an IC50 value of 0.4 µM. The remaining compounds showed moderate to weak activity, with IC50 values in the range of 6.9-15.3 µM. Compounds 7 and 12 were active against human oral carcinoma (KB) cells with IC50 values of 2.4 and 3.7 µM, respectively. Additionally, compounds 7 and 12 displayed antifungal activity against Candida albicans with the respective MIC values of 1 and 2 µg/mL and were active against Cryptococcus neoformans with equal MIC values of 4 µg/mL.

Cytotoxic xanthones from the roots of Mesua ferrea L.

Five undescribed xanthones, 4-methoxypyranojacareubin, 4-hydroxy-3-prenylpyranoxanthone, 1-hydroxy-5,7-dimethoxyxanthone, 5-hydroxy-1,6,7-trimethoxyxanthone and 2-hydroxy-1,5-dimethoxyxanthone, together with thirty-three known xanthones were isolated from the roots of Mesua ferrea L. The structures of all isolated xanthones were elucidated based on spectroscopic methods. 5-Hydroxy-1,6,7-trimethoxyxanthone and 2-hydroxy-1,5-dimethoxyxanthone were also confirmed by X-ray diffraction data. In addition, the isolated compounds were determined for antibacterial, antioxidant and cytotoxic activities. The known 1,5,6-trihydroxyxanthone showed cytotoxicity against A375, PC-3 and HaCaT cell lines with IC50 values of 5.73 µg/mL, 5.93 µg/mL and 8.94 µg/mL, respectively.

Asperidines A-C, pyrrolidine and piperidine derivatives from the soil-derived fungus Aspergillus sclerotiorum PSU-RSPG178.

One new pyrrolidine derivative, asperidine A (1), and two new piperidine derivatives, asperidines B (2) and C (3), were isolated from the soil-derived fungus Aspergillus sclerotiorum PSU-RSPG178 together with two known alkaloids. Compound 3 possessed an unprecedented 7-oxa-1-azabicyclo[3.2.1]octane skeleton with four chiral centers. Their structures were determined by spectroscopic evidence. The absolute configurations of compounds 2 and 3 were established using Mosher's method and further confirmed for compound 3 by X-ray crystallographic data. Compound 2 dose-dependently inhibited the CFTR-mediated chloride secretion in T84 cells with an IC50 value of 0.96 µM whereas 3 displayed the same activity with the IC50 value of 58.62 µM. Compounds 2 and 3 also significantly reduced intracellular ROS under both normal and H2O2-treated conditions compared with their respective controls in a dose-dependent manner without cytotoxic effect on Caco-2 cells. In addition, compound 3 was inactive against noncancerous Vero cells whereas compound 2 was considered to be inactive with the IC50 value of >10 µM.

TBAI/TBHP-Mediated Cascade Cyclization toward Sulfonylated Indeno[1,2-c]quinolines.

Treatment of ortho-amino-substituted aryldiyne derivatives with sulfonyl hydrazides in the presence of tetrabutylammonium iodide (TBAI) and tert-butyl hydroperoxide (TBHP) led to a cascade cyclization reaction to yield sulfonylated indeno[1,2-c]quinolines in moderate to good yields. The features of the methodology include metal-free reaction, the ease of reagent handling, and a broad functional group tolerance.

γ-Butenolide and furanone derivatives from the soil-derived fungus Aspergillus sclerotiorum PSU-RSPG178.

Chromatographic separation of the broth extract of the soil-derived fungus Aspergillus sclerotiorum PSU-RSPG178 resulted in isolation of four γ-butenolide-furanone dimers, aspersclerotiorones A-D, a furanone derivative, aspersclerotiorone E, and two γ-butenolide derivatives, aspersclerotiorones F and G, together with six known compounds, penicillic acid, dihydropenicillic acid, 5,6-dihydro-6-hydroxypenicillic acid, 6-methoxy-5,6-dihydropenicillic acid, coculnol and (4R,5R)-4,5-dihydroxy-3-methoxy-5-methylcyclohex-2-en-1-one. Their structures were determined by spectroscopic evidence. For aspersclerotiorones A and B, the structures were confirmed by single-crystal X-ray diffraction crystallography. Penicillic acid displayed weak antibacterial activity against Staphylococcus aureus and Escherichia coli with equal MIC values of 128 µg/mL, and it was noncytotoxic towards African green monkey kidney fibroblast cells.

Crystal structure and Hirshfeld-surface analysis of (benzene-carbo-thio-amide-κS)bromido-bis-(tri-phenylphosphane-κP)silver(I).

The title complex, [AgBr(C7H7NS)(C18H15P)2], was obtained from the reaction of silver(I) bromide with benzene-carbo-thio-amide (C7H7NS) and tri-phenyl-phosphane (C18H15P) in the mixed solvent of aceto-nitrile and ethanol. The mononuclear complex exhibits a distorted tetra-hedral coordination geometry about the metal atom, arising from one S atom of a benzene-carbo-thio-amide ligand, two P atoms of two tri-phenyl-phosphane mol-ecules and one bromide ion. An intra-molecular N-H⋯Br hydrogen bond is observed and in the crystal structure, inversion dimers linked by pairs of N-H⋯Br and C-H⋯Br hydrogen bonds are observed. In addition, C-H⋯π inter-actions occur, leading to [101] chains. Hirshfeld-surface analyses are presented and discussed.

Lovastatin Analogues from the Soil-Derived Fungus Aspergillus sclerotiorum PSU-RSPG178.

Three new lovastatin analogues (1, 4, and 5) together with four known lovastatin derivatives, namely, lovastatin (2), α,ß-dehydrolovastatin (3), α,ß-dehydrodihydromonacolin K (6), and α,ß-dehydro-4a,5-dihydromonacolin L (7), were isolated from the soil-derived fungus Aspergillus sclerotiorum PSU-RSPG178. Their structures were established using spectroscopic evidence. Compound 5 exhibited the most potent activity against HMG-CoA reductase, with an IC50 value of 387 µM. In addition, the present study indicated the direct interaction of compound 5 with HMG-CoA reductase. Compound 5 was considered to be noncytotoxic against noncancerous Vero cells, with an IC50 value of 40.0 µM, whereas compound 2 displayed much stronger activity, with an IC50 value of 2.2 µM.

Terezine derivatives from the fungus Phoma herbarum PSU-H256.

Investigation of the fungus Phoma herbarum PSU-H256 isolated from a leaf of Hevea brasiliensis resulted in the isolation of eight terezine derivatives (E-L) together with four known compounds. Their structures were established by analysis of spectroscopic evidence. For terezines E and H, their structures were confirmed by single-crystal X-ray diffraction crystallography. In addition, the absolute configuration at C-7 in terezine E was established by Mosher's method. Terezines K and L were tested for antibacterial, antimalarial, antimycobacterial and cytotoxic activities, but were inactive.

Crystal structure of di-chlorido-bis-[2-(phenyl-diazen-yl)pyridine-κN (1)]zinc.

The structure of the title complex, [ZnCl2(C11H9N3)2], comprises two 2-(phenyl-diazen-yl)pyridine ligands coordin-ating to a central Zn(II) dichloride unit via the pyridyl N-atom donors, resulting in a slightly distorted tetra-hedral geometry. The complex exhibits twofold rotation symmetry, with the rotation axis bis-ecting the zinc cation. The structure is stabilized by weak inter-molecular C-H⋯Cl inter-actions [C⋯Cl = 3.411 (2) and 3.675 (2) Å], connecting neighbouring mol-ecules into layers perpendicular to the c axis.