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501.
502.
Rachel Serrano Víctor Gonzlez-Menndez Germn Martínez Clara Toro Jesús Martín Olga Genilloud
Jos R. Tormo 《Molecules (Basel, Switzerland)》2021,26(14)
Microbial natural products are an invaluable resource for the biotechnological industry. Genome mining studies have highlighted the huge biosynthetic potential of fungi, which is underexploited by standard fermentation conditions. Epigenetic effectors and/or cultivation-based approaches have successfully been applied to activate cryptic biosynthetic pathways in order to produce the chemical diversity suggested in available fungal genomes. The addition of Suberoylanilide Hydroxamic Acid to fermentation processes was evaluated to assess its effect on the metabolomic diversity of a taxonomically diverse fungal population. Here, metabolomic methodologies were implemented to identify changes in secondary metabolite profiles to determine the best fermentation conditions. The results confirmed previously described effects of the epigenetic modifier on the metabolism of a population of 232 wide diverse South Africa fungal strains cultured in different fermentation media where the induction of differential metabolites was observed. Furthermore, one solid-state fermentation (BRFT medium), two classic successful liquid fermentation media (LSFM and YES) and two new liquid media formulations (MCKX and SMK-II) were compared to identify the most productive conditions for the different populations of taxonomic subgroups. 相似文献
503.
López JG Fernández I Ruiz MS Ortiz FL 《Chemical communications (Cambridge, England)》2007,(44):4674-4676
The first C(alpha),C(ortho) dilithium complex of a phosphazene has been synthesized as a single stereoisomer and has been structurally characterized in solution; the complex is monomeric, with the dianion acting as an N-C(ortho) and O-C(alpha) chelate. Transmetallation with Me(3)SnCl and PhHgCl afforded the first C(alpha),C(ortho) homo- and hetero-bimetallic phosphazene complexes, which contain a desymmetrised Ph(2)PN moiety. 相似文献
504.
505.
Degtyareva O Hernández ER Serrano J Somayazulu M Mao HK Gregoryanz E Hemley RJ 《The Journal of chemical physics》2007,126(8):084503
The high-pressure phases of group-VI elements sulfur and selenium in their spiral chain and ring structures are examined by in situ Raman and x-ray diffraction techniques combined with first principles electronic structure calculations. The S-II, S-III, Se-I, and Se-VII having spiral chain structures and S-VI with a molecular six-member ring structure are studied in a wide P-T range. The square spiral chain structure of S-III and Se-VII is characterized by seven Raman modes that harden with increasing pressure. The calculations reproduce the observed frequencies and allow the authors to make the mode assignment. The "p-S" and "hplt" phases of sulfur reported by previous Raman studies are identified as S-II and S-III with the triangular and square spiral chain structures, respectively. The phase relations obtained by the x-ray and Raman measurements show that the high-pressure high-temperature phases of sulfur, observed by x-ray, can be induced by laser illumination at room temperature. 相似文献
506.
Serrano P Casas J Llebaria A Zucco M Emeric G Delgado A 《Journal of combinatorial chemistry》2007,9(4):635-643
Libraries of succinamic acid derivatives resulting from the condensation of a series of succinic acid derivatives with amines are reported as putative khafrefungin analogues. A total of 480 compounds derived from the initial condensation of 8 scaffolds with 60 different amines have been synthesized using automated technology with the help of scavenger resins. A simple acetate hydrolysis of five of the above sublibraries afforded additional 300 compounds for a total of 780 compounds. Around 55% of the library members showed purities higher than 70% (HPLC-ELS-MS) thus proving the generality of this approach. Results on growth inhibition of the yeast Saccharomyces cerevisiae in the presence of selected library members are also reported as a preliminary evaluation of the antifungal activity. 相似文献
507.
Pérez A Serrano JL Sierra T Ballesteros A de Saá D Barluenga J 《Journal of the American Chemical Society》2011,133(21):8110-8113
The supramolecular architectures of a fluorophore are controlled through the design of a conjugated polycatenar molecule, the self-assembly of which can be addressed toward a columnar liquid-crystalline phase and organogels. Thus, depending on the environmental conditions for self-assembly, compound CA9 organizes into an unprecedented hexagonal columnar mesophase in the condensed state, in which half a molecule constitutes the slice of the column, or into a rectangular mesomorphic-like organization in the presence of apolar solvents such as cyclohexane and dodecane, at a concentration in which fibers form and gelling conditions are fulfilled. In this Col(r)-type arrangement, the organization within the columns depends on the solvent. All of the materials prepared show luminescence, and moreover, a remarkable 3-fold increase in fluorescence intensity was observed in going from the solution to the gel state. 相似文献
508.
Santana MD García-Bueno R García G Sánchez G García J Pérez J García L Serrano JL 《Dalton transactions (Cambridge, England : 2003)》2011,40(14):3537-3546
The direct reaction between the hydroxo-complexes [{Pd(μ-OH)(C^N)}(2)] and protonated S^N-donor ligands to yield new dinuclear cyclometallated palladium(ii) complexes containing -NCS- bridging heterocyclic thionates of general formula [{Pd(μ-N^S)(C^N)}(2)] (C^N = 2-(2-pyridyl)phenyl (Phpy) I; = 7,8-benzoquinolyl (Bzq) II; N^S = pyrimidine-2-thionate (Spym) 1, benzoimidazolidine-2-thionate (Sbimid) 2, 1-methylimidazoline-2 thionate (Smeimid) 3) is described. The related mononuclear complexes [Pd(N^S)(C^N)] N^S = 2-aminothiophenolate (Atph) 4) were prepared in a similar way. Photophysical properties were investigated together with those of complexes with related ligands pyridin-2-thionate (Spy) 5 and pyrrole-2-carboxaldehydate (2-pcal) 6. All the compounds absorb intensely below 300 nm via(1)LC transitions located in Bzq or Phpy ligands, and display additional low energy absorptions of mixed (1)MLCT-(1)LC character. In the solid state diffuse reflectance UV-vis spectra, the differences are notable for dinuclear complexes. The complexes under study are quite unusual in terms of luminescence behaviour, since most of them are emissive in solution at room temperature and all display intense emissions in frozen CHCl(3) solution, but also in the solid state at 298 and 77 K. Emission quantum yields are in the range 2.52-0.14%, similar to that of related complexes. Structural characterisation by X-ray diffraction of complexes II3 and II6 confirmed the proposed formula. 相似文献
509.
Dong CK Urgaonkar S Cortese JF Gamo FJ Garcia-Bustos JF Lafuente MJ Patel V Ross L Coleman BI Derbyshire ER Clish CB Serrano AE Cromwell M Barker RH Dvorin JD Duraisingh MT Wirth DF Clardy J Mazitschek R 《Chemistry & biology》2011,18(12):1602-1610
Here we report the discovery of tetracyclic benzothiazepines (BTZs) as highly potent and selective antimalarials along with the identification of the Plasmodium falciparum cytochrome bc1 complex as the primary functional target of this novel compound class. Investigation of the structure activity relationship within this previously unexplored chemical scaffold has yielded inhibitors with low nanomolar activity. A combined approach employing genetically modified parasites, biochemical profiling, and resistance selection validated inhibition of cytochrome bc1 activity, an essential component of the parasite respiratory chain and target of the widely used antimalarial drug atovaquone, as the mode of action of this novel compound class. Resistance to atovaquone is eroding the efficacy of this widely used antimalarial drug. Intriguingly, BTZ-based inhibitors retain activity against atovaquone resistant parasites, suggesting this chemical class may provide an alternative to atovaquone in combination therapy. 相似文献
510.
Jiménez J Laguna A Molter AM Serrano JL Barberá J Oriol L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(3):1029-1039
New liquid crystals having a non‐conventional structure have been synthesised from a six‐armed cyclotriphosphazene core, [N3P3(OC6H4OH‐4)6], which was condensed with polycatenar acids. Reactions were monitored by 31P{1H} and 1H NMR spectroscopy and the chemical structure of the resulting materials was confirmed by different spectroscopic techniques and mass spectrometry (MALDI‐TOF). Results were in accordance with monodisperse, fully functionalised cyclotriphosphazenes. Thermal and mesomorphic properties were studied by optical microscopy, differential scanning calorimetry and X‐ray diffraction. All of the synthesised phosphazenes, substituted with benzyl ether chains, show a high thermal stability and exhibit mesomorphic properties, which depend on the number and type of alkyl terminal chains located at the periphery of the mesogens. Mesomorphic properties range from Colh for cph‐A1 and cph‐A2 to a cubic phase detected for cph‐A3 , which has the larger number of alkyl chains. Furthermore, helical order was detected on X‐ray data of cph‐A2 , which has chiral branched chains. Circular dichroism spectra of annealed films at mesophase temperature show a signal attributed to the chiral helical arrangement of the mesogenic chromophores. 相似文献