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Three new metal(II)–organic coordination complexes, formula as [Cd3(btc)2(3-dpna)2(H2O)2]·8H2O (1), [Zn3(btc)2(3-dpna)2(H2O)2]·4H2O (2) and [Co3(btc)2(3-dpna)2(H2O)2]·2H2O (3) [3-dpna = N1,N4-di(pyridin-3-yl)naphthalene-1,4-dicarboxamide, H3btc = 1,2,4-benzenetricarboxylic acid], have been successfully synthesized by the hydrothermal methods. Complexes 1–3 exhibit similar 3D coordination networks based on the [M3(btc)2(H2O)2]n [M = Cd(II) for 1, Zn(II) for 2, Co(II) for 3] layers and the μ2-bridging 3-dpna ligand containing the naphthalene-bridging group, representing a 4,4,4-connected {42.64}4{64.82} topology. The photocatalyitc properties of complexes 1–3 toward degrading organic dyes, the fluorescent of complexes 1–3 and the fluorescent sensing activities of complexes 1–2 toward detecting metal ions have been studied. Additionally, the electrochemical and electrocatalytic properties of complex 3 have been investigated. [ABSTRACT FROM AUTHOR]

Three new zinc(II)/cobalt(II) coordination complexes [Zn(HBTB)(L)0.5] (1), [Zn(HCPPA)(L)] (2), and [Co(HCPPA)(L)]·2H2O (3) [H3BTB = 1,3,5‐tri(4‐carboxylphenyl)benzene, H3CPPA = 5‐(4‐carboxyl‐phenoxy)‐isophthalic acid, L = N1,N4‐bis(3‐pyridyl)naphthaldiamide] were solvothermally synthesized. The structural characterization reveals that complex 1 represents a 3D coordination framework with a binodal 3,4‐connected {4.102}2{4.105}2 topology constructed from the 2D [Zn(HBTB)]n polymeric double‐layers and the bidentate L ligands. Complex 2 is a 1D metal‐organic chain derived from the dinuclear [Zn2(HCPPA)2] loops and [Zn2(L)2] loops. Complex 3 possesses a binodal 3,5‐connected {42.6}{43.6.84.102} topological 2D layered architecture based on the [Co2(HCPPA)2] ribbon chains and the bidentate L ligands. For 2 and 3, their adjacent chains or layers are respectively stacked into 3D supramolecular architectures via the hydrogen bonds. Moreover, the fluorescent and fluorescent sensing activities towards small solvent molecules of coordination complexes 1 and 2, the photocatalyitc properties of 1–3 towards organic dyes were studied. [ABSTRACT FROM AUTHOR]

Two new zinc(II) coordination complexes [Zn(pda)(3-bpcd)0.5] (1) and [Zn(pda)(3-bpoa)]·H2O (2) have been synthesized by self-assembly of 1,2-phenylenediacetic acid (H2pda), semi-rigid/or flexible bis(pyridyl)-bis(amide) ligands [3-bpcd = N,N′-bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide, 3-bpoa = N,N'-bis(3-pyridyl)octandiamide] and zinc nitrate. Complex 1 is a 2 D layered framework derived from the 1 D [Zn(pda)]2n ribbon-like chain and the bidentate 3-bpcd, which is a (3,4)-connected (42·63·8)(42·6) topology, then the adjacent layers are linked by hydrogen bonds to build a 3 D supramolecular network. Complex 2 displays a 3 D framework based on the 1 D [Zn(pda)]2n ribbon-like chains and the 1 D [Zn(3-bpoa)]n chains, which represents a (3,5)-connected (42.65.83)(42.6) topology. Two bis(pyridyl)-bis(amide) ligands with different flexibilities play an important role in constructing final topological structures for title complexes. Moreover, the fluorescent properties of two zinc(II) complexes and their fluorescent sensing properties toward small solvent molecules have been studied. Additionally, the photocatalytic properties of complexes 1 − 2 toward the degradation of dyes have been investigated. [ABSTRACT FROM AUTHOR]

Homogentisate solanesyltransferase (HST) is a crucial enzyme in the plastoquinone biosynthetic pathway and has recently emerged as a promising target for herbicides. In this study, we successfully expressed and purified a stable and highly pure form of seven times transmembrane protein Chlamydomonas reinhardtii HST (CrHST). The final yield of CrHST protein obtained was 12.2 mg per liter of M9 medium. We evaluated the inhibitory effect on CrHST using Des-Morpholinocarbony Cyclopyrimorate (DMC) and found its IC50 value to be 3.63 ± 0.53 μM, indicating significant inhibitory potential. Additionally, we investigated the substrate affinity of CrHST with two substrates, determining the Km values as 22.76 ± 1.70 μM for FPP and 48.54 ± 3.89 μM for HGA. Through sequence alignment analyses and three-dimensional structure predictions, we identified conserved amino acid residues forming the active cavity in the enzyme. The results from molecular docking and binding energy calculations indicate that DMC has a greater binding affinity with HST compared to HGA. These findings represent substantial progress in understanding CrHST's properties and potential for herbicide development. Key points: • First high-yield transmembrane CrHST protein via E. coli system • Preliminarily identified active cavity composition via activity testing • Determined substrate and inhibitor modes via molecular docking [ABSTRACT FROM AUTHOR]

Shikonin exhibits powerful anticancer activities for various cancer cells, but its poor solubility and strong toxicity hinder its development as clinical anticancer agent. We previously confirmed that shikonin and its derivatives can disturb mitosis through targeting tubulin. In this study, α -lipoic acid, the naturally-occurring co-factor of pyruvate dehydrogenase (PDH), was introduced into shikonin to design the twin drugs against both mitosis (tubulin) and glycolysis (PDK). 18 kinds of α -lipoic acid shikonin ester derivatives were achieved through three rounds of screening process performed by computer assistant drug design method, being designated as the outstanding compounds. Among them, 1c displayed the most potent cytotoxicity towards cervical cancer cells (HeLa) with an IC 50 value of 3.14 ± 0.58 μM and inhibited xenotransplanted tumor growth in a dose-dependent manner. Further pharmacologic study demonstrated that 1c can cause cell cycle arrest in G2/M phase as tubulin polymerization inhibitor. Moreover, it also showed good PDK1 inhibitory activity, promoting PDH activity and forced HeLa cells to process more aerobic metabolism to undergo cell apoptosis. We reported here the first dual inhibitors of tubulin and PDK1 based on shikonin. It may form a basis for shikonin optimization through twin drug design framework for the discovery of new and potent shikonin derivatives in the study of targeted cancer therapy. [ABSTRACT FROM AUTHOR]

Two new coordination polymers (CPs), namely, [Cu(4-bptzp)(BDC)] ( 1 ) and [Cu 2 (4-bptzp) 2 (BDC)Cl 2 ] ( 2 ) (4-bptzp = 1,4-bis(5-(4-pyridyl)tetrazolyl)propane, H 2 BDC = 1,3-benzenedicarboxylic acid) were synthesized by changing the proportion of the solvents under the solvothermal conditions, and structurally characterized by single crystal X-ray diffraction, infrared spectroscopy (IR), powder X-ray diffraction (PXRD), elemental analyses and thermogravimetric analyses (TGA). The 4-bptzp was firstly introduced into the CPs. Complexes 1 and 2 show two kinds of 1D chain structures. Complex 1 contains the 1D ladder-like [Cu(BDC)] n chains and Cu 2 (4-bptzp) 2 rings, while complex 2 consists of the 1D linear [Cu 2 (BDC)Cl 2 ] n chain containing the bridging Cl − ions and Cu 2 (4-bptzp) 2 rings. The adjacent 1D chains in 1 and 2 are extended to 2D supramolecular layers by the hydrogen bonding interactions, respectively. In addition, the electrochemical properties and dye adsorption properties of complexes 1 and 2 have been investigated. The solvent ratio plays a key role in adjusting their structures and adsorption property. [ABSTRACT FROM AUTHOR]