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排序方式: 共有71条查询结果,搜索用时 93 毫秒
41.
Karol Al Ayed Ross D. Ballantine Michael Hoekstra Samantha J. Bann Charlotte M. J. Wesseling Alexander T. Bakker Zheng Zhong Yong-Xin Li Nora C. Brüchle Mario van der Stelt Stephen A. Cochrane Nathaniel I. Martin 《Chemical science》2022,13(12):3563
Brevicidine and laterocidine are two recently discovered lipopeptide antibiotics with promising antibacterial activity. Possessing a macrocyclic core, multiple positive charges, and a lipidated N-terminus, these lipopeptides exhibit potent and selective activity against Gram-negative pathogens, including polymyxin-resistant isolates. Given the low amounts of brevicidine and laterocidine accessible by fermentation of the producing microorganisms, synthetic routes to these lipopeptides present an attractive alternative. We here report the convenient solid-phase syntheses of both brevicidine and laterocidine and confirm their potent anti-Gram-negative activities. The synthetic routes developed also provide convenient access to novel structural analogues of both brevicidine and laterocidine that display improved hydrolytic stability while maintaining potent antibacterial activity in both in vitro assays and in vivo infection models.Convenient solid-phase approaches are described for the synthesis of brevicidine and laterocidine. Also reported are novel analogues including a laterocidine variant with enhanced hydrolytic stability and potent in vivo antibacterial activity. 相似文献
42.
43.
The ammonium 6 salt resulting from the reaction of the DABCO and the allyl bromide 2 was converted with good yields into a new family of dimethyl 3-amino itaconates 5. 相似文献
44.
A highly efficient and versatile method for the synthesis of 3‐acyl‐5‐aryl or arylsulfonylpyridin‐2‐ones and 3‐alkyl‐5‐aryl‐2‐hydroxybenzamides in one step via regiospecific cyclocondensation reaction of β‐keto‐amides with vinamidinium salts is described. 相似文献
45.
Thouraya GmizaMohamed Adnen Hadj Ayed Jamel Eddine KhiariBéchir Ben Hassine 《Tetrahedron letters》2011,52(7):764-766
Α series of substituted 3-acyl-6-aryl-2-pyridones have been prepared in one-step reactions via condensation of 3-aryl-3-chloropropeniminium salts with β-keto-amides. This efficient synthesis has the advantages of high yields and simple reaction procedures. 相似文献
46.
An inorganic compound formulated as K5NH4[TeMo6O24].Te(OH)6.6H2O (1) has been isolated by conventional solution method and structurally characterized by single-crystal X-ray diffraction methods, scanning electron microscopy (SEM), IR, UV–vis spectra, and cyclic voltammetry measurements. This compound crystallizes in the monoclinic system, space group C2/c with unit a = 18.6841(1) Å, b = 10.0513(1) Å, c = 21.1065(1) Å, β = 116.495(1)°, V = 3547.49(4) Å3, Z = 4, R = 0.033 and wR (F2) = 0.087 for 3432 unique observed reflexions [I > 2σ(I)]. The crystal structure of (1) is built up from an Anderson clusters connected through hydrogen-bonding interactions into a three-dimensional supramolecular network. 相似文献
47.
Montiel-Palma V Muñoz-Hernández MA Ayed T Barthelat JC Grellier M Vendier L Sabo-Etienne S 《Chemical communications (Cambridge, England)》2007,(38):3963-3965
Reaction of a phosphinobenzylsilane compound with ruthenium complexes leads to C-H and/or Si-H activation. The new complex Ru{eta(2)-H-SiMe2CH(o-C(6)H(4))PPh2}2 (5) was isolated and X-ray, NMR and DFT studies reveal that 5 displays two agostic Si-H interactions and two carbon-metallated bonds. 相似文献
48.
Khouloud Jebri Marie-Rose Mazières Stéphanie Ballereau Taïcir Ben Ayed Jean-Christophe Plaquevent Michel Baltas Frédéric Guillen 《Tetrahedron letters》2014
Ionic liquids are solvents general enough to conduct a multi-step process in organic synthesis. We show that both the preparation of starting materials (thioacetals and enoxysilane) as well as their coupling can be realized in such medium. 相似文献
49.
Al-Shihri AS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(5):1189-1192
A new polydentate Schiff base (H3L) was synthesized from the condensation of 2,6-diformyl-4-methylphenol and S-methylhydrazine-carbodithionate. The 1:1 metal complexes were obtained from the interaction of H3L and the metal ions Cr(III), Co(II), Ni(II), Cu(II), Cd(II) and Hg(II). The complexes were characterized by elemental analysis and IR spectroscopy. Detailed studies of the thermal properties of the complexes were investigated by thermogravimetry techniques. 相似文献
50.
Afef Ghouili Michal Dusek Vaclav Petricek Taïcir Ben Ayed Rached Ben Hassen 《Journal of Physics and Chemistry of Solids》2014
A new coumarin chalcone 3-((2E)-3-(2-hydroxyphenyl) prop-2-enoyl)-4-hydroxy-2(H)-chromen-2-one was synthesized using the Claisen Schmidt reaction by the condensation of 3-acetyl-4-hydroxycoumarin and 2-hydroxybenzaldehyde using a mild organic base. This novel compound was characterized by 1H NMR, FT-IR and UV–vis spectroscopy. Single crystal X-ray diffraction investigation at low temperature (T=120 K) shows that this compound exhibits an intramolecular O3–H…O hydrogen bond, the coumarin ring and the phenyl group are nearly coplanar and the crystal packing is stabilized by intermolecular O3–H…O contacts and π–π stacking interactions. This ortho-hydroxyphenyl-4-hydroxycoumarin chalcone exhibits a strong blue-green emission under visible light excitation at 470 nm. The fluorescence behaviors of this compound doped in poly(methyl methacrylate) (PMMA) were investigated. 相似文献