Rapid Identification of Corn Sugar Syrup Adulteration in Wolfberry Honey Based on Fluorescence Spectroscopy Coupled with Chemometrics.

Honey adulteration has become a prominent issue in the honey market. Herein, we used the fluorescence spectroscopy combined with chemometrics to explore a simple, fast, and non-destructive method to detect wolfberry honey adulteration. The main parameters such as the maximum fluorescence intensity, peak positions, and fluorescence lifetime were analyzed and depicted with a principal component analysis (PCA). We demonstrated that the peak position of the wolfberry honey was relatively fixed at 342 nm compared with those of the multifloral honey. The fluorescence intensity decreased and the peak position redshifted with an increase in the syrup concentration (10-100%). The three-dimensional (3D) spectra and fluorescence lifetime fitting plots could obviously distinguish the honey from syrups. It was difficult to distinguish the wolfberry honey from another monofloral honey, acacia honey, using fluorescence spectra, but it could easily be distinguished when the fluorescence data were combined with a PCA. In all, fluorescence spectroscopy coupled with a PCA could easily distinguish wolfberry honey adulteration with syrups or other monofloral honeys. The method was simple, fast, and non-destructive, with a significant potential for the detection of honey adulteration.

Novel nitrogen mustard-artemisinin hybrids with potent anti-leukemia action through DNA damage and activation of GPx.

The incidence of various types of cancers is increasing every year. Among these, leukemia is extremely common, and thus, developing novel drugs to combat leukemia is crucial. In this study, we designed and synthesized several hybrids and obtained a new lead molecule 5a, with a strong therapeutic effect on leukemia. The results indicated that most hybrids effectively inhibited the growth of leukemia cells, HCT-116, and A549 cancer cells with an IC50 of <10 µM. Among these hybrids, 5a and 4h showed significant anticancer activity against CCRF-CEM, with IC50 values of 0.895 µM and 0.555 µM, respectively. Particularly, 5a had lower toxicity to L02 than chlorambucil (CLB) and doxorubicin (Dox), and the high selectivity was also reflected in the normal human B lymphoblast cell line (IM9). Upon investigating the mechanism of action, we found that 5a downregulated Bcl-2 and caused DNA double-stranded breaks (DSBs) to induce several genotoxic stress responses. The results of the flow cytometry assay showed that 5a was a non-specific molecule in the cell cycle. Furthermore, 5a did not affect total ROS levels but significantly improved the activity of glutathione peroxidase (GPx). Preliminary studies showed that nitrogen mustard exerted an efficient effect, and 5a can combine the advantages of artemisinin and nitrogen mustard and exhibit effects superior to either. This study showed that 5a should be further investigated as a therapeutic compound against leukemia.

Ketoprofen and Loxoprofen Platinum(IV) Complexes Displaying Antimetastatic Activities by Inducing DNA Damage, Inflammation Suppression, and Enhanced Immune Response.

Metastasis is a major contributor of death in cancer patients, and there is an urgent need for effective treatments of metastatic malignancies. Herein, ketoprofen (KP) and loxoprofen (LP) platinum(IV) complexes with antiproliferative and antimetastatic properties were designed and prepared by integrating chemotherapy and immunotherapy targeting cyclooxygenase-2 (COX-2), matrix metalloproteinase-9 (MMP-9), and programmed death ligand 1 (PD-L1), besides DNA. A mono-KP platinum(IV) complex with a cisplatin core is screened out as a candidate possessing potent anti-proliferative and anti-metastasis activities both in vitro and in vivo. It induces serious DNA damage and further leads to high expression of γ-H2AX and p53. Moreover, it promotes apoptosis of tumor cells through mitochondrial apoptotic pathway Bcl-2/Bax/caspase3. Then, COX-2, MMP-9, NLRP3, and caspase1 as pivotal enzymes igniting inflammation and metastasis are obviously inhibited. Notably, it significantly improves immune response through restraining the expression of PD-L1 to increase CD3+ and CD8+ T infiltrating cells in tumor tissues.

Rapid and selective detection of biothiols by novel ruthenium(II) complex-based phosphorescence probes.

Considering the excellent photochemical properties of ruthenium(II) complexes, two new ruthenium(II) complexes, RuL1-DNBS and RuL2-DNBS, have been developed as phosphorescence probes for detection of biothiols in 100:1 (v/v) Hepes buffer (20 mM, pH = 7.2)/CH3CN solution. The response rate was highly improved of these two probes toward biothiols because the steric interactions between 1H-imidazo [4, 5-f] [1,10] phenanthroline group and ortho-2, 4-dinitrobenzensulfonate resulted in a relatively rapid thiol-induced SNAr substitution reaction. RuL1-DNBS and RuL2-DNBS were weakly phosphorescent owing to the effectual photoinduced electron transfer from ruthenium(II) luminophore to the sensing group, 2,4-dinitrobenzenesulfonyl. After reacting with biothiols, the 2,4-dinitrobenzenesulfonyl group of RuL1-DNBS and RuL2-DNBS were cleavaged and the RuL1 and RuL2 were obtained. Meanwhile, the phosphorescence were "turn-on". Both of these two probes can detect biothiols sensitively and selectively under physiological conditions with submicromolar detection limits. Furthermore, application of RuL2-DNBS for detecting of intracellular biothiols has been successfully performed in living Glioma cells.

Lewis Base-Catalyzed [4 + 3] Annulation of ortho-Quinone Methides and MBH Carbonates: Synthesis of Functionalized Benzo[ b]oxepines Bearing Oxindole Scaffolds.

A novel Lewis base-catalyzed [4 + 3] annulation process for the construction of benzo[ b]oxepine scaffolds has been developed. 1,4-Diazabicyclo[2.2.2]octane (DABCO) promotes the union of o-QMs and Morita-Baylis-Hillman carbonates in reasonable to excellent yields and good stereoselectivities (dr > 20:1). This straightforward, catalytic approach offers access to a variety of synthetically useful benzo[ b]oxepine derivatives bearing oxindole scaffolds containing all-carbon spiro-quaternary stereocenters.

A FRET based ratiometric fluorescent probe for detection of sulfite in food.

A new fluorophore pyrido[1,2-a]benzimidazole based ratiometric fluorescent probe for the selective detection of sulfite ions in water was investigated. It shows large (pseudo) Stokes shifts (260 nm), high FRET efficiency, high selectivity and sensitivity. A distinct color change from red to colorless was observed and importantly, it proves to be a convenient and efficient tool to detect the sulfite levels in sugar samples.

Solvatochromism, acidochromism and aggregation-induced emission of propeller-shaped spiroborates.

Propeller-shaped pyridyl-enolato-catecholate/-salicyl spiroborates (Sborepy1-6) were synthesized. The complexes Sborepy3-6 show weak emission in fluid solution and aggregation-induced emission enhancement in the aggregation state with large Stokes shifts of 4025-5237 cm-1. Moreover, intense solid-state emissions with high Φf ranging from 25% to 37% were observed for Sborepy3-6 owing to the weak intermolecular interactions in their solid-state. The AIE and intense solid-state emission have been revealed via the X-ray diffraction analysis and theoretical calculations. Furthermore, the solvatochromism in the solution state and the potential application as a fluorescent acidic vapour sensor in the solid state of Sborepy3 and Sborepy6 were also demonstrated.

AIE-active boron complexes based on benzothiazole-hydrazone chelates.

A new family of aggregation-induced emission (AIE)-active monoboron and bisboron complexes based on benzothiazole-hydrazone chelates was synthesized. These complexes showed very weak fluorescence in fluid solution due to active intramolecular rotation and were emissive in high-viscosity solvents or in the aggregation state. Single crystal X-ray diffraction analyses and theoretical calculations were carried out to explain AIE behavior. The large Stokes shifts (3590-7400 cm-1) and relatively highly efficient solid-state emission make these complexes valuable AIE luminophores for further potential applications.

Copper- and Palladium-Catalyzed Cross-Coupling Reactions for the Synthesis of N-Fused Benzo[4,5]imidazo[2,1-b]thiazole Derivatives via Substituted trans-1,2-Diiodoalkenes, 1H-Benzo[d]imidazole-2-thiols, and Halobenzenes.

Two transition metal (Cu and Pd)-catalyzed C-S, C-N, and C-C bond cross-coupling reactions for the preparation of N-fused benzo[4,5]imidazo[2,1-b]thiazole derivatives were developed. A variety of 3-substituted and 2,3-disubstituted benzo[4,5]imidazo[2,1-b]thiazoles were efficiently and conveniently synthesized from the coupling reaction via trans-1,2-diiodoalkenes, 1H-benzo[d]imidazole-2-thiols, and halobenzenes in moderate to excellent yields.

Preparative separation of polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin coupled with preparative high performance liquid chromatography.

In this study, a preparative separation method was developed for isolation of eleven polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin (MAR) coupled with preparative high performance liquid chromatography (PHPLC). Water-soluble fraction of Chinese propolis was first "prefractioned" using MAR, which yielded four subfractions. The four subfractions were then isolated by PHPLC with an isocratic elution of methanol-water. Finally, eleven polyphenols were purified from Chinese propolis including caffeic acid, ferulic acid, isoferulic acid, 3,4-dimethoxy cinnamic acid, pinobanksin, caffeic acid benzyl ester, caffeic acid phenethyl ester, apigenin, pinocembrin, chrysin and galangin. The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. The method developed was simple, effective, rapid, scalable and economical, and it was a promising basis for large-scale preparation of multiple components from natural products.

{4-Amino-N'-[(2-oxidonaphthalen-1-yl)methyl-idene]benzohydrazidato}di-methyl-tin(IV).

In the title compound, [Sn(CH3)2(C18H13N3O2)], the Sn(IV) ion is coordinated by one N and two O atoms from the tridentate 4-amino-N'-[(2-oxidonaphthalen-1-yl)methyl-idene]benzohydrazidate(2-) ligand and two C atoms from methyl ligands in a distorted trigonal-bipyramidal geometry. The dihedral angle between the naphthalene ring system and the benzene ring is 19.2 (2)°. In the crystal, weak N-H⋯O hydrogen bonds link the mol-ecules into zigzag chains along [010].

An efficient preparative procedure for main flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography.

In this study, a simple and efficient preparative procedure was developed for preparation of seven flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography (SPHPLC). First, the ethyl acetate fraction from the peel of T. kirilowii Maxim. obtained "prefractionation" using polyamide resin, which yielded two subfractions. And then the two subfractions were isolated by SPHPLC with an isocratic elution of methanol-water. Finally, seven known flavonoids were purified from 35 g of ethyl acetate extract including quercetin-3-O-[α-l-rhamnose (1→2)-ß-d-glucopyranosyl]-5-O-ß-d-glucopyranoside (19 mg), quercetin-3-O-rutinoside (24 mg), apigenin-7-O-ß-d-glucopyranoside (10mg), diosmetin-7-O-ß-d-glucopyranoside (45 mg), luteolin (21 mg), apigenin (15 mg), and diosmetin (56 mg). The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. In the present study, a simple, effective, and rapid procedure was established for preparative separation of multiple components from the peel of T. kirilowii Maxim. Furthermore, it was scalable and economical, so it was a promising basis for large-scale preparation of flavonoids from other plant extracts.

{4-Chloro-N'-[(2-oxidonaphthalen-1-yl-κO)methyl-idene]benzohydrazidato-κ(2) N',O}di-methyl-tin(IV).

In the title complex, [Sn(CH3)2(C18H11ClN2O2)], the Sn(IV) ion is coordinated by two O atoms and an N atom from a 4-chloro-N'-[(2-oxidonaphthalen-1-yl)methyl-idene]benzohydrazidate ligand and two C atoms from two methyl ligands in a distorted trigonal-bipyramidal geometry [Sn-O = 2.092 (3) and 2.144 (3) Å; Sn-N = 2.160 (4) Å]. The dihedral angle between the naphthalene ring system and the benzene ring is 8.6 (2)°. In the crystal, adjacent mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming a chain along the b-axis direction.

Synthesis, structural characterization and in vitro cytotoxicity of diorganotin (IV) diimido complexes.

Reactions of the diorganotin with two N-OH diimide ligands (N-hydroxyphthalimide and N-hydroxysuccinimide) yielded five new dimeric tetraorganostannoxanes formulated as R(8)Sn(4)O(2)L(2)X(2). The crystal structures of the complexes reveal the formation of the tetranuclear species contains a planar Sn(4)O(4) core, consisting of three adjacent rhombs with bridging oxo and N-OH diimide ligands. The central tin atoms are five-coordinated to assume a distorted trigonal bipyramidal configuration and the N-OH diimide ligands act as monodentate O-bound planar. In vitro cytotoxic activities of the title compounds have been determined against three cell lines (A549, HCT-8 and HL-60). Studies reveal that three di-n-butyltin(IV) diimido complexes show higher cytotoxic activities than cisplatin. The structure-activity relationship of the cytotoxicity of the title complexes has also been discussed.

[2-(4-Chloro-phen-yl)-1,3-selenazol-4-yl]methanol.

In the title compound, C10H8ClNOSe, the dihedral angle between benzene and selenazole rings is 11.4 (3)° and the hy-droxy-methyl group is bent from the selenazole ring, making a dihedral angle of 63.8 (3)°. In the crystal, mol-ecules are linked into inversion dimers by pairs of O-H⋯N hydrogen bonds. Roof-tile-like stacking of the mol-ecules along [010] [b = 4.5707 (4) Å] is observed, with the benzene and selenazole rings separated by a face-to-face distance of 3.57 Šand a mutual slippage of 2.85 Å.

trans-Tris(4-bromo-phen-yl)dichlorido-antimony(V).

The Sb(V) atom in the title compound, [SbCl2(C6H4Br)3], has an almost regular trigonal-bipyramidal geometry with the equatorial plane made up of three C atoms of the bromo-phenyl groups and the axial positions occupied by two Cl(-) ions in a trans configuration. In the crystal, C-H⋯Br hydrogen bonds link the mol-ecules into zigzag chains along the b-axis direction. Pairs of C-H⋯Cl hydrogen bonds further link mol-ecules into cyclic dimers with R2(2)(10) ring motifs, generating a three-dimensional network.

(E)-4-[2-(2-Hy-droxy-benzo-yl)-hydra-zin-ylidene]penta-noic acid.

The title mol-ecule, C(12)H(14)N(2)O(4), adopts a trans configuration with respect to the C=N double bond. The amino group is involved in an intra-molecular N-H⋯O hydrogen bond. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into doubled sheets parallel to the (101) plane.

{1-[(2-Oxidonaphthalen-1-yl)methylidene]thiosemicarbazidato-κN,O,S}diphenyl-tin(IV).

The asymmetric unit of the title compound, [Sn(C(6)H(5))(2)(C(12)H(9)N(3)OS)], contains two independent mol-ecules with almost identical configurations. In each mol-ecule, the Sn(IV) atom is coordinated by O, N and S atoms from a (2-oxido-1-naph-thaldehyde)-thio-semicarbazonato ligand and two C atoms from phenyl rings in a distorted trigonal-bipyramidal geometry. Weak inter-molecular N-H⋯O and N-H⋯S hydrogen bonds link four mol-ecules into a centrosymmetric tetra-mer. The crystal packing exhibits short inter-molecular S⋯S contacts of 3.335 (3) Å.

(E)-2-(Isonicotinoylhydrazonometh-yl)benzoic acid methanol monosolvate.

The title compound, C(14)H(11)N(3)O(3)·CH(4)O, was synthesized by the condensation reaction of isonicotinohydrazide with an equimolar quantity of 2-formyl-benzoic acid in methanol. The hydrazone mol-ecule displays an E configuration about the C=N bond. The dihedral angel between the pyridine and the benzene rings is 12.04 (5)°. In the crystal structure, mol-ecules are linked by O-H⋯N, O-H⋯O and N-H⋯O hydrogen-bonding inter-actions.

3-Eth-oxy-2-(1,3-thia-zol-2-yl)isoindolin-1-one.

In the title compound, C(13)H(12)N(2)O(2)S, the dihedral angles between the isoindolone ring system and the thia-zole ring and the eth-oxy group are 6.50 (11) and 89.0 (2)°, respectively.