Search

Botrytis cinerea, Rhizoctonia solani and Hemileia vastatrix are three species of phytopathogenic fungi behind major crop losses worldwide. These have been selected as target models for testing the fungicide potential of a series of bis(ylidene) cyclohexanones. Although some compounds of this chemical class are known to have inhibitory activity against human pathogens, they have never been explored for the control of phytopathogens until now. In the present work, bis(ylidene) cyclohexanones were synthesized through simple, fast and low-cost base- or acid-catalyzed aldol condensation reaction and tested in vitro against B. cinerea, R. solani and H. vastatrix. bis(pyridylmethylene) cyclohexanones showed the highest activity against the target fungi. When tested at 200 nmol per mycelial plug against R. solani., these compounds completely inhibited the mycelial growth, and the most active bis(pyridylmethylene) cyclohexanone compound had an IC

For the first time, we herein report on the syntheses of two new Ru(II)/bipyridine/phenanthroline complexes containing lapachol as ligand: complex (1), [Ru (bipy)

In this study, novel ruthenium(III) complexes with hydroxybenzophenones with the general formula cis-[RuCl2(HB)(dppb)] were obtained, where HB = 2-hydroxy-4-(octyloxy)benzophenone (C1), 2-hydroxy-4-methoxybenzophenone (C2), 2,2′-dihydroxy-4,4′-dimethoxybenzophenone (C3), 2,2′-dihydroxy-4-methoxybenzophenone (C4), 2,4-dihydroxybenzophenone (C5), and 2,4,4′-trihydroxybenzophenone (C6), and dppb = 1,4-bis(diphenylphosphine)butane. These compounds were characterized by elemental analysis, molar conductivity, cyclic voltammetry, infrared and UV-vis spectroscopy, and powder X-ray diffraction. The crystal structures of C2, C3, C4, and C5 were determined by single-crystal X-ray diffraction analysis which confirmed the bidentate coordination of the carbonyl and phenolate oxygens of HB with ruthenium(III). Additionally, the cis geometry and electronic transitions of C1–C6 were investigated using DFT calculations. Finally, the comparative activity against promastigote forms of L. amazonensis was made available for the ligands HB1–HB6 and C1–C6. The ligands significantly inhibited the proliferation of promastigote forms, confirming the results previously published by some of us. Unfortunately, their respective complexes showed no activity. It is important to emphasize that the leishmanicidal activity of 2,2′-dihydroxy-4,4′-dimethoxybenzophenone (HB3), 2,2′-dihydroxy-4-methoxybenzophenone (HB4), and 2,4,4′-trihydroxybenzophenone (HB6) ligands is reported here for the first time. Despite the fact that they were less active against promastigote forms when compared to amphotericin B, two of them (HB4 and HB6) were less cytotoxic to J774 macrophages.

In this work we present the synthesis and characterization of six new ruthenium compounds with general formulae [Ru(L)(dppb)(bipy)]PF

Here we discovered an unprecedented giant octahedral coordination compound bearing 16 Zn2+, 12 Na+, 8 O2-, 4 OH-, 13 H2O and 6 L4- ligands [L4- = fully deprotonated tetra(carboxymethoxy)calix[4]arene]. Its structure was elucidated by single-crystal X-ray diffraction, wavelength-dispersive X-ray spectroscopy and MALDI-TOF mass spectrometry. This compound, Zn8Na6L6⊃Zn8Na6O8(OH)4(H2O)13 (external⊃internal), has eight tetrahedral zinc ions forming the coordination vertices of an outermost cube where carboxylate groups from the sodium calixarenes are anchored. Its core consists of eight Zn2+, six Na+, eight O2-, and four OH- distributed over three layers, besides thirteen coordinated H2O molecules.

Background: Breast cancer is one of the most common types among women. Its incidence progressively increases with age, especially after age 50. Platinum compounds are not efficient in the treatment of breast cancer, highlighting the use of other metals for the development of new chemotherapeutic agents. Objective: This paper aims to obtain three new ruthenium compounds that incorporate sulfur amino acids in their structures and to investigate their cytotoxic activity in breast tumor cell lines. Methods: Complexes with general formula [Ru(AA)(dppb)(bipy)] (complexes 1 and 2) or [Ru(AA)(dppb) (bipy)]PF6 (complex 3), where AA = L-cysteinate (1), D-penicillaminate (2), and L-deoxyalliinate (3), dppb = 1,4-bis(diphenylphosphino)butane and 2,2´-bipyridine, were obtained from the cis-[RuCl2(dppb)(bipy)] precursor. The cytotoxicity of the complexes on MDA-MB-231 (triple negative human breast cancer); MCF-7 (double positive human breast cancer) and V79 (hamster lung fibroblast) was performed by the MTT (4,5- dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) method. The control agent was the cisplatin, which is a commercially available drug for cancer treatment. Results: In complexes (1) and (2), the ligands are coordinated to the metal center by nitrogen and sulfur atoms, while in complex (3) coordination is through the oxygen and nitrogen atoms. These suggestions are based on the infrared and 31P1H NMR data. For complexes (1) and (2), their X-ray structures were determined confirming this suggestion. The three complexes are stable in a mixture of DMSO (80 %) and biological medium (20 %) for at least 48 h and presented cytotoxicity against the MDA-MB-231 and MCF-7 tumor cells with reasonable selectivity indexes. Conclusion: Our work demonstrated that ruthenium complexes containing sulfur amino acids, bipyridines and bisphosphines showed cytotoxicity against the MDA-MB-231 and MCF-7 cancer cell lines, in vitro, and that they interact weakly with the DNA (Deoxyribonucleic Acid) and the HSA (Human Serum Albumin) biomolecules.

In a previous work, the natural compound drynaran, namely E-3-(5-hydroxymethyl)furan-2-yl)-2-phenylacrylaldehyde, was isolated from the Asian medicinal plant Drynaria bonii. Although this plant is used for several therapeutic purposes, drynaran was isolated in small quantities and, therefore, evaluated only for a few biological activities. Here, we propose a simple, fast, diastereoselective, and green synthesis of drynaran, using ethanol as solvent and 5-hydroxymethylfurfural as starting material. Drynaran was obtained in 66% yield and 98:2 E:Z diastereoisomeric ratio. The method was also used to produce a series of drynaran analogues, some of them as pure E-isomer and others in E:Z ratio of at least 90:10. Besides, five drynaran analogues formed crystals with suitable qualities for single-crystal X-ray diffraction data collection, and their crystal structures are described for the first time.

O acido 3,4,5-triacetobenzoico produzido a partir da esterificacao do acido 3,4,5-triidroxibenzoico (acido galico) representa uma alternativa complementar ao arsenal disponivel para o controle de micro-organismos patogenicos, notadamente aqueles formadores de biofilmes microbianos. Os biofilmes dificultam a acao dos agentes antimicrobianos e promovem a resistencia aos antimicrobianos classicos e a possiveis falhas terapeuticas. Estrategias como a derivacao de compostos de origem natural e estudo do impacto destas modificacoes nas atividades biologicas sao adotadas com o intuito de aumentar a eficacia e diminuir a toxicidade dos derivados contra a formacao de biofilmes microbianos, pois estes desempenham um papel relevante no contexto das doencas infecciosas recalcitrantes e de dificil controle. Com base no exposto, foram estudadas a sintese e derivacao do acido 3,4,5-triacetobenzoico, a toxicidade do composto com o ensaio contra Artemia salina e as atividades antimicrobianas e inibitoria da formacao de biofilme in vitro pelas seguintes cepas-padrao bacterianas: Pseudomonas aeruginosa ATCC 9027, Burkholderia cepacia ATCC 17759, Escherichia coli ATCC 25312, Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 1228 e Kocuria rhizophila ATCC 9341. Os resultados encontrados demonstraram que o rendimento da sintese foi de 73%, que composto apresentou toxicidade e atividade antimicrobiana moderada e que 1000 ?g.mL -1 do acido 3,4,5-triacetobenzoico inibiu a formacao de biofilme por todas as bacterias estudadas, fato que reforca a potencialidade do composto na inibicao deste importante fator de virulencia microbiano.

Ruthenium complexes with piplartine, [Ru(piplartine)(dppf)(bipy)](PF6)2 (1) and [Ru(piplartine)(dppb)(bipy)](PF6)2 (2) (dppf = 1,1-bis(diphenylphosphino) ferrocene; dppb = 1,4-bis(diphenylphosphino)butane and bipy = 2,2′-bipyridine), were recently synthesized and displayed more potent cytotoxicity than piplartine in different cancer cells, regulated RNA transcripts of several apoptosis-related genes, and induced reactive oxygen species (ROS)-mediated apoptosis in human colon carcinoma HCT116 cells. The present work aimed to explore the underlying mechanisms through which these ruthenium complexes induce cell death in HCT116 cells in vitro, as well as their in vivo action in a xenograft model. Both complexes significantly increased the percentage of apoptotic HCT116 cells, and co-treatment with inhibitors of JNK/SAPK, p38 MAPK, and MEK, which inhibits the activation of ERK1/2, significantly reduced the apoptosis rate induced by these complexes. Moreover, significant increase in phospho-JNK2 (T183/Y185), phospho-p38α (T180/Y182), and phospho-ERK1 (T202/Y204) expressions were observed in cells treated with these complexes, indicating MAPK-mediated apoptosis. In addition, co-treatment with a p53 inhibitor (cyclic pifithrin-α) and the ruthenium complexes significantly reduced the apoptosis rate in HCT116 cells, and increased phospho-p53 (S15) and phospho-histone H2AX (S139) expressions, indicating induction of DNA damage and p53-dependent apoptosis. Both complexes also reduced HCT116 cell growth in a xenograft model. Tumor mass inhibition rates were 35.06, 29.71, and 32.03% for the complex 1 (15 μmol/kg/day), complex 2 (15 μmol/kg/day), and piplartine (60 μmol/kg/day), respectively. These data indicate these ruthenium complexes as new anti-colon cancer drugs candidates.

Made available in DSpace on 2018-12-11T17:03:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Three ruthenium complexes [RuCl(CTZ)(bipy)(P-P)]PF6 [P-P = 1,2-bis(diphenylphosphino)ethane (dppe-1), 1,4-bis(diphenylphosphino)butane (dppb-2) and 1,1′-bis(diphenylphosphino)ferrocene (dppf-3), bipy = 2,2′-bipiridine and clotrimazole (CTZ) 1-[(2-chlorophenyl)diphenylmethyl]-1H-imidazole] were synthesized. These complexes were characterized by a combination of elemental analysis, molar conductivity, infrared and UV–vis spectroscopy, 1H, 13C{1H} and 31P{1H} nuclear magnetic resonance techniques, cyclic voltammetry and mass spectroscopy. Bovine serum albumin binding constants, which were in the range of 1.30–36.00 × 104 M− 1, and thermodynamic parameters suggest spontaneous interactions with this protein by electrostatic forces due to the positive charge of the complexes. DNA interactions studied by spectroscopic titration, viscosity measurements, gel electrophoresis, circular dichroism, ethidium bromide displacement and reactions with guanosine and guanosine monophosphate indicated the DNA binding affinity primarily through non-covalent interactions. All complexes 1–3 were tested against the human carcinoma cell lines MCF-7 (breast), A549 (lung) and DU-145 (prostate) presenting promising IC50 values, between 0.50 and 14.00 μM, in some cases lower than the IC50 for the reference drug (cisplatin). The antimicrobial activity assays of the complexes provided evidence that they are potential agents against mycobacterial infections, specifically against Mycobacterium tuberculosis H37Rv. Departamento de Química Universidade Federal de São Carlos-SP Departamento de Gerontologia Universidade Federal de São Carlos-SP Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas UNESP Directoria de Metrologia Aplicada a Ciências da Vida Instituto Nacional de Metrologia Qualidade e Tecnologia INMETRO Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas UNESP FAPESP: 13/03513-9 CNPq: 141738/2013-8 CNPq: 141739/2013-4

A comprehensive investigation of anhydrous form of 3,4,5-Triacetoxybenzoic acid (TABA) is reported. Single crystal X-ray diffraction, Thermal analysis, Fourier Transform Infrared spectroscopy (FTIR) and DFT calculations were applied for TABA characterization. This anhydrous phase crystallizes in the triclinic [Formula: see text] space group (Z' = 1) and its packing shows a supramolecular motif in a classical [Formula: see text] ring formed by acid-acid groups association. The phase stability is accounted in terms of supramolecular architecture and its thermal behaviour. Conformation search at B3LYP/6-311++G(2d,p) level of theory shows the existence of three stable conformers and the most stable conformation was found experimentally. The reactivity of TABA was investigated using the molecular orbital theory and molecular electrostatic potential. The calculation results were used to simulate the infrared spectrum. There is a good agreement between calculated and experimental IR spectrum, which allowed the assignment of the normal vibrational modes.