Synthesis and Anticancer Activity Assessment of Zelkovamycin Analogues.

The zelkovamycin family is a class of cyclic octapeptides with potent antibacterial and antiviral activity. Due to their unique chemical structures and excellent bioactivity, zelkovamycins have consistently attracted the interest of synthetic chemists. However, only the total synthesis of zelkovamycin and zelkovamycin G has been reported until now.

Structure of the green heme isolated from allylbenzene-modified chloroperoxidase: A novel heme architecture implicating the mechanisms of CPO inactivation and epoxidation.

The chemical identification of the modified heme (the green heme) during chloroperoxidase catalyzed epoxidation of allylbenzene remains unestablished due to its high instability within the protein matrix, the absence of paramagnetically shifted signals, and the difficulty in obtaining crystals of the modified enzyme. We have established the unambiguous structure of the modified prosthetic heme group, which was extracted from the protein matrix using D NMR spectroscopy and LC-MS spectrometry. The modified heme was isolated as a µ-oxo dimer that can be quantitatively converted to the corresponding monomer.

Platinum(II) diimine complexes containing phenylpyridine ligands decorated with anionic -monocarborane clusters [CBH].

We report three Pt(II) diimine complexes containing ancillary ligands of phenylpyridine furnished with anionic -monocarborane clusters [CBH]. Three neutral complexes exhibit intensive phosphorescence in the solid state and complex 1 was used to detect acetonitrile vapor in a quartz plate.

Novel glycosylation zinc(II)-cryptolepine complexes perturb mitophagy pathways and trigger cancer cell apoptosis and autophagy in SK-OV-3/DDP cells.

With the aim of shedding some light on the mechanism of action of zinc(II) complexes in antiproliferative processes and molecular signaling pathways, three novel glycosylated zinc(II)-cryptolepine complexes, i.e., [Zn(QA1)Cl] (Zn(QA1)), [Zn(QA2)Cl] (Zn(QA2)), and [Zn(QA3)Cl] (Zn(QA3)), were prepared by conjugating a glucose moiety with cryptolepine, followed by complexation of the resulting glycosylated cryptolepine compounds N-((1-(2-morpholinoethyl)-1H-1,2,3-triazol-4-yl)methyl)-benzofuro[3,2-b]quinolin-11-amine (QA1), 2-(4-((benzofuro[3,2-b]quinolin-11-ylamino)methyl)-1H-1,2,3-triazol-1-yl)ethan-1-ol (QA2), and (2S,3S,4R,5R,6S)-2-(4-((benzofuro[3,2-b]quinolin-11-ylamino)-methyl)-1H-1,2,3-triazol-1-yl)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol (QA3) with zinc(II), and their anticancer activity was evaluated.

Green and multifunctional chitosan-based conformal coating as a controlled release platform for fruit preservation.

Food waste caused by the decay of perishable foods is a serious global issue. However, traditional preservative materials don't perform well in preventing food decay. Here, a green and multifunctional conformal coating is prepared by the hydrogen-bonding interactions among chitosan, nano-humic acid and curcumin, which is different from traditional preservative films obtained by solution blending.

A triphenylphosphine coordinated cinnamaldehyde-derived copper(I) Fenton-like agent with mitochondrial aggregation damage for chemodynamic therapy.

Chemodynamic therapy (CDT), which uses agents to induce cell death by decomposing endogenous hydrogen peroxide (HO) into highly toxic hydroxyl radicals (˙OH), has been recognized as a promising approach to treat cancer. However, improving the efficiency of ˙OH production is considered one of the biggest challenges that limits the therapeutic efficacy of CDT. Herein, to controllably and efficiently induce oxidative damage through the production of ˙OH, we developed a new metal complex CDT agent with atomically precise structural characteristics as a deviation from traditional nanomaterial-CDT agents.

Rational construction of a triphenylphosphine-modified tetra-nuclear Cu(I) coordinated cluster for enhanced chemodynamic therapy.

A triphenylphosphine-modified tetra-nuclear Cu(I) coordinated cluster was constructed for enhanced chemodynamic therapy (CDT) by increasing the number of metal centers. Once inside human bladder cancer (T24) cells, a larger amount of copper accumulated compared with the mono-nuclear Cu(I) complex; the additional copper could generate more •OH and then induce more obvious apoptosis a Fenton-like reaction, thus further increasing the tumor inhibition effect and ultimately improving the CDT efficiency.

A simple and feasible atom-precise biotinylated Cu(i) complex for tumor-targeted chemodynamic therapy.

A simple and feasible atom-precise biotinylated Cu(i) complex, which can catalyze HO overexpressed commonly in the tumor microenvironment to produce ˙OH through a Fenton-like reaction, was prepared and employed as an effective agent for tumor-targeted chemodynamic therapy.

Constructing an unprecedented {Mn} matryoshka doll with a [Mn(CO)] inorganic core and magnetocaloric effect.

An unprecedented inner [Mn(CO)] inorganic core and [Mn] metal-organic periphery compose a high-nuclearity homometallic single-valent {Mn} molecular aggregate with a [Mn] ⊂ [Mn] ⊂ [Mn] ⊂ [Mn] matryoshka doll-like skeleton that displays a significant magnetocaloric effect (MCE).

Hierarchical Construction and Magnetic Difference of {CoM} (M = Co/Cd) Aggregates from {Co} Cluster-Based Precursors in the Presence of Homo/Heterometal Salts.

The controllable construction and function expansion of some sophisticated aggregations represent a current hot topic in scientific research. In this paper, using a prefabricated {Co} cluster as a synthetic precursor, a homometallic {Co} and a heterometallic {CoCd} giant cluster possessing similar dual-[M] (M = Co/Cd) skeletons was prepared by reacting the precursor with excess CoCl and Cd(OAc) salts, respectively. The detailed structural information on {Co} and {CoCd} was characterized by single-crystal X-ray diffraction and further analyzed by X-ray photoelectron spectroscopy, inductively coupled plasma-mass spectroscopy, and scanning electron microscopy with energy dispersive X-ray (EDX) spectroscopy in the solid state.

Two groups of copper pyridine-triazole complexes with "open or close" pepper rings and their antitumor activities.

Based on 1,2-dimethoxyphenyl (veratrole, open) and 1,2-methylenedioxyphenyl (pepper ring, close)-derived pyridine-triazole analogues, two groups of copper(ii) complexes, namely, Group I(C1-C3) and Group II(C4-C6) were synthesized and fully characterized. All ligands and complexes were tested by MTT assays on seven tumour cell lines (T24, Hep-G2, Sk-Ov-3, MGC-803, HeLa, A549 and NCI-H460) and one normal liver cell line (HL-7702). Surprisingly, the pepper-ring-derived complexes (C4-C6) showed significantly enhanced cytotoxicity compared with the 1,2-bimethoxyphenyl ring-derived complexes (C1-C3) and the standard anticancer drug cisplatin.

A novel sandwich shaped {CoCoMo} cluster with a Co triangle encapsulated in two capped CoCoMoO fragments.

A novel discrete {Co14Mo24} nanoscale cluster, {CoIII2CoII10Cl2(dpbt)3(H2O)2[CoIIMoV12O31(CH3O)9]2}·24CH3OH (1) (here, dpbt = 5,5'-di(pyridin-2-yl)-3,3'-bi(1,2,4-triazole)), with a triangular Co4 core encapsulated in two novel capped Co-substituted Keggin-type Co5Mo12O40 anions, has been isolated from alkaline methanol solution. The high-resolution electrospray ionization mass spectrum (HRESI-MS) of microcrystalline 1 in MeOH/CH2Cl2 (v : v = 2 : 1) was recorded. Two prominent overlapping peaks in the range of m/z = 2740-2840 and 1820-1880 for the discrete fragments of [CoIII2CoII12MoV24O62Cl2(dpbt)3(H2O)2(CH3O)x(OH)18-x-2H]2- (x = 9-18, F1) and [CoIII2CoII12MoV24O62Cl2(dpbt)3(H2O)2(CH3O)x(OH)19-x-2H]3- (x = 6-13, F2), respectively, are obtained, confirming the {Co14Mo24} composition in 1.

In Situ Metal-Ligand Reactions under Solvent-Dependent Hydro(solvo)thermal Conditions: Structures, Mass Spectrometry, and Magnetism.

In this study, four in situ hydro(solvo)thermal metal-ligand reactions, including oxidation (HL), C-C coupling (HL), nitration (HL), and condensation (HL), based on bis[3-(pyridin-2-yl)-1-1,2,4-triazol-5-yl]methane (HL), in the presence of Dy ions, were carried out. The in situ metal-ligand reaction gave six new ligands existing in eight novel Dy coordination complexes, which were characterized by crystal structure, mass spectrometry, and magnetism.

Schiff base complex conjugates of bovine serum albumin as artificial metalloenzymes for eco-friendly enantioselective sulfoxidation.

Artificial metalloenzymes (BSA-ML) have been prepared by non-covalent insertion of transition metal Schiff-base complexes, ML (L = 2-hydroxynaphthalen-1-naphthaldehyde and 3,4-diaminobenzenesulfonic acid; M = Co, Mn, V, Fe, Cr), into bovine serum albumin (BSA) as the host protein and were characterized by UV-visible spectroscopy, ESI-TOF mass spectrometry and molecular docking studies. The catalytic activities of the BSA-ML in the selective oxidation of various prochiral sulfides in aqueous media, using HO as oxidant, have been evaluated. During the optimization process, pH and the concentrations of catalyst and oxidant were found to have a remarkable influence on both yield and enantioselectivity.

Hierarchical Assembly of a {Co} Cluster from Two Vertex-Fused {Co} Clusters and Their Single-Molecule Magnetism.

We present the synthesis, structural characterization, and magnetic properties of two high-nuclearity cobalt clusters formulated as [Co(μ-OH)(μ-Cl)(dpbt)(ptd)Cl][Co(HO)Cl]·(CH)CHOH (1) and [Co(μ-OH)(μ-Cl)(dpbt)(ptd)Cl]·2CHCHOH (2), respectively (Hdpbt = 5,5'-bis(pyridin-2-yl)-3,3'-bis(1,2,4-triazole) and Hptd = 3-(pyridin-2-yl)-1,2,4-triazine-5,6-diol). Compound 1 is composed of an inner [Co(μ-OH)(μ-Cl)] cubane and an outer [Co(dpbt)(ptd)Cl] defective adamantane. Compound 2 reveals a giant {Co} cluster possessing a dual-[Co] skeleton from 1.

Ni(II) Complexes with Schiff Base Ligands: Preparation, Characterization, DNA/Protein Interaction and Cytotoxicity Studies.

In this study, two Ni(II) complexes, namely [Ni(HL1)₂(OAc)₂] () and [Ni(L2)₂] () (where HL1 and HL2 are ()-1-((1-(2-hydroxyethyl)-1-pyrazol-5-ylimino)methyl)-naphthalen-2-ol) and ()-ethyl-5-((2-hydroxynaphthalen-1-yl)methyleneamino)-1-methyl-1-pyrazole-4-carboxylate, respectively), were synthesized and characterized by X-ray crystallography, Electrospray Ionization Mass Spectrometry (ESI-MS), elemental analysis, and IR. Their uptake in biological macromolecules and cancer cells were preliminarily investigated through electronic absorption (UV-Vis), circular dichroism (CD) and fluorescence quenching measurements. Bovine serum albumin (BSA) interaction experiments were investigated by spectroscopy which showed that the complexes and ligands could quench the intrinsic fluorescence of BSA through an obvious static quenching process.

Bovine serum albumin-cobalt(ii) Schiff base complex hybrid: an efficient artificial metalloenzyme for enantioselective sulfoxidation using hydrogen peroxide.

An artificial metalloenzyme (BSA-CoL) based on the incorporation of a cobalt(ii) Schiff base complex {CoL, H2L = 2,2'-[(1,2-ethanediyl)bis(nitrilopropylidyne)]bisphenol} with bovine serum albumin (BSA) has been synthesized and characterized. Attention is focused on the catalytic activity of this artificial metalloenzyme for enantioselective oxidation of a variety of sulfides with H2O2. The influences of parameters such as pH, temperature, and the concentration of catalyst and oxidant on thioanisole as a model are investigated.

Synthesis, characterization, DNA/protein interaction and cytotoxicity studies of Cu(II) and Co(II) complexes derived from dipyridyl triazole ligands.

Four different transition metal complexes containing dipyridyl triazole ligands, namely [Cu(abpt)2Cl2]·2H2O (1), [Cu(abpt)2(ClO4)2] (2), [Co2(abpt)2(H2O)2Cl2]·Cl2·4H2O (3) and [Co2(Hbpt)2(CH3OH)2(NO3)2] (4) have been designed, synthesized and further structurally characterized by X-ray crystallography, ESI-MS, elemental analysis, IR and Raman spectroscopy. In these complexes, the both ligands act as bidentate ligands with N, N donors. DNA binding interactions with calf thymus DNA (ct-DNA) of the ligand and its complexes 1~4 were investigated via electronic absorption, fluorescence quenching, circular dichroism and viscosity measurements as well as confocal Laser Raman spectroscopy.

An intuitional hierarchical assembly of cluster-organic frameworks with a thickness of 1.97 nm from a discrete Co14 cluster.

An intuitional hierarchical assembly, metaphorically referred to as a "blossom and yield fruit" process, from a discrete cluster {[Co14(CH3O)4(dpbt)6Cl12]·14CH3OH, ()} to 2D cluster organic frameworks {[Co14(CH3O)10(dpbt)6 Cl6]·12CH3OH, ()}, has been established. The magnetic ordering of was obviously improved compared with .

The Spectroscopy Study of the Binding of an Active Ingredient of Dioscorea Species with Bovine Serum Albumin with or without Co(2+) or Zn(2+).

Diosgenin (DIO) is the active ingredient of Dioscorea species. The interaction of DIO with bovine serum albumin (BSA) was investigated through spectroscopic methods under simulated physiological conditions. The fluorescence quenching data revealed that the binding of DIO to BSA without or with Co(2+) or Zn(2+) was a static quenching process.

Binding of engeletin with bovine serum albumin: insights from spectroscopic investigations.

In this paper, several spectroscopic techniques were used to investigate the interaction of engeletin (ELN) with bovine serum albumin (BSA). The analysis of UV-Vis absorption and fluorescence spectra revealed that ELN and BSA formed a static complex ELN-BSA, and ELN quenched the fluorescence of BSA effectively. According to the thermodynamic parameters ΔS(0) = 47.

Study on the structural changes of bovine serum albumin with effects on polydatin binding by a multitechnique approach.

Polydatin is a traditional Chinese medicine which shows effective biological activity as antimicrobial and antiviral agent. The secondary structure changes of bovine serum albumin (BSA) were investigated by the methods of Fourier transform infrared spectroscopy (FT-IR), circular dichroism (CD) and Raman spectroscopy. The experimental results indicated that polydatin changed the secondary structure of BSA.