- Design of receptors for urea derivatives based on the pyrido[3,2-g]indole subunit
-
The Fischer cyclization of appropriate 8-quinolinylhydrazones was employed to prepare a series of cavity-shaped hosts consisting of a central pyridine ring appended in either the 2,6- or 3,5-positions by two pyrido[3,2-g]indole subunits. The pyridine and
- Hegde, Vidyadhar,Hung, Chi-Ying,Madhukar, Puttannachetty,Cunningham, Raymond,H?pfner, Thomas,Thummel, Randolph P.
-
-
Read Online
- A novel potent metal-binding NDM-1 inhibitor was identified by fragment virtual, SPR and NMR screening
-
NDM-1 can hydrolyze nearly all available β-lactam antibiotics, including carbapenems. NDM-1 producing bacterial strains are worldwide threats. It is still very challenging to find a potent NDM-1 inhibitor for clinical use. In our study, we used a metal-binding pharmacophore (MBP) enriched virtual fragment library to screen NDM-1 hits. SPR screening helped to verify the MBP virtual hits and identified a new NDM-1 binder and weak inhibitor A1. A solution NMR study of 15N-labeled NDM-1 showed that A1 disturbed all three residues coordinating the second zinc ion (Zn2) in the active pocket of NDM-1. The perturbation only happened in the presence of zinc ion, indicating that A1 bound to Zn2. Based on the scaffold of A1, we designed and synthesized a series of NDM-1 inhibitors. Several compounds showed synergistic antibacterial activity with meropenem against NDM-1 producing K. pneumoniae.
- Bai, Weiqi,Cheng, Kai,Gao, Yan,Guo, Huifang,He, Wei,Li, Conggang,Li, Zhuorong,Wu, Cai
-
-
- PHOTOCHROMIC HYDRAZONE SWITCHES
-
Provided herein are compounds for use as photochromic molecular switches having very long thermal isomerization half-lives and switchable fluorescence properties both in solution and the solid state.
- -
-
Paragraph 00217
(2018/05/24)
-
- A trivalent cobalt complex with the new redox-active ligand 10-(8-quinolylazo)-9-phenanthrol (qapl)
-
In this work, we describe the two-step synthesis of a new quinoline substituted arylazo ligand bearing a phenanthrol substituent 1 (qapl). This new ligand does not exhibit keto/enol tautomerization in solution as does papl, a structurally related arylazo ligand. Qapl can be reduced quasi-reversibly suggesting that the formed radical anion features better stability than the radical formed from papl. Density functional theory calculations indicate highly π-delocalized frontier orbital levels with large π-antibonding coefficients on the azo N atoms in the LUMO. Coordination of qapl to CoCl2 produced a trivalent cobalt complex 2 and single crystal X-ray diffraction studies revealed a six-coordinate cobalt(III) ion with the tridentate qapl ligand binding through quinoline N, azo N and phenanthrol O donor atoms. The electronic structure of 2 is shown to be similar to related complex [Co(papl)2]+ and DFT calculations confirm low energy absorptions bands to feature mostly ligand centered transitions with some LMCT character mixed in.
- Taylor, Robin A.,Bonanno, Nico M.,Mirza, Danyal,Lough, Alan J.,Lemaire, Martin T.
-
-
- Catalytic Coupling between Unactivated Aliphatic C-H Bonds and Alkynes via a Metal-Hydride Pathway
-
We report a Rh(I)-catalyzed site-selective coupling between ketone β-C(sp3)-H bonds and aliphatic alkynes using an in situ-installed directing group. Upon hydrogenation or hydration, various β-alkylation or β-aldol products of the ketones are obtained with broad functional group tolerance. Mechanistic investigations support the involvement of a Rh-H intermediate through oxidative addition of Rh(I) into the β-C-H bonds. Thus, to the best of our knowledge, this transformation represents the first example of catalytic couplings between unsaturated hydrocarbons and unactivated aliphatic C-H bonds via a metal-hydride pathway.
- Xu, Yan,Young, Michael C.,Dong, Guangbin
-
supporting information
p. 5716 - 5719
(2017/05/04)
-
- Study of synthesis of some pyrroloquinolines, pyrroloisoquinolines, pyridocarbazoles and their derivatives
-
The new isomers of pyrroloquinolines, pyrroloisoquinolines and pyridocarbazoles have been synthesized from the hydrazone of methylisopropylketone, 2-methylcyclohexanone, 5 and 8-quinolylhydrazine and 5-isoquinolylhydrazine by ring closure in AcOH at reflux in excellent yields. The methiodide of pyrroloisoquinoline and pyridocarbazole were reduced with NaBH4 at room temperature to produce corresponding hexahydropyrroloisoquinoline and decahydropyridoisoquinoline in good yields.
- Fathalipour, Soghra,Shahrokhnia, Nazila,Afghan, Arash,Baradarani, Mehdi M.
-
experimental part
p. 5808 - 5814
(2010/12/24)
-
- The synthesis of 4-(3,3-dimethyl-3H-pyrrolo[2,3-f] quinolin-2-yl)pyrazoles and 4-(3,3-dimethyl-3H-pyrrolo[3,2-h] quinolin-2-yl)pyrazoles
-
(Chemical Equation Presented) 5-Hydrazinoquinoline and 8-hydrazinoquinoline were converted via Fischer syntheses with 3-methylbutan-2-one into pyrido-indolenines 2,3,3-trimethyl-3H-pyrrolo[2,3-f]quinoline 7 and 2,3,3-trimethyl-3H-pyrrolo[ 3,2-h]quinoline 11, respectively. Exposure of the indolenines to the Vilsmeier reagent produced aminomethylene-malondialdehydes 8 and 12, which reacted with hydrazine or arylhydrazines to give 4-(3H-pyrrolo[2,3-f]quinolin-2-yl)- and 4-(3H-pyrrolo[3,2-h]quinolin-2-yl)- pyrazoles, 9 and 13.
- Rashidi,Afghan,Baradarani, Mehdi M.,Jouleb, John A.
-
body text
p. 428 - 431
(2009/09/25)
-
- 2-Substituted 1H-pyrrolo [3,2-h] quinoline derivatives: Synthesis and aspects of their biological activity
-
Certain 2-substituted 1H-pyrrolo [3,2-h] quinolines have been prepared and their biological activity in mammalian cells and in some microrganisms have been studied. These compounds represent a simplified ellipticine heterocyclic moiety: in addition they have a different ring condensation, leading to an angular molecular structure instead of a linear one. In mammalian cells all compounds appeared to be able of inducing an antiproliferative effect and an extensive DNA fragmentation, similarly to ellipticine, even if to a reduced extent. The new derivatives behaved in a comparable way also on some microrganisms, such as T2 bacteriophage (which appears to be less sensitive than mammalian cells) and in mutagenesis tests carried out with E. coli WP2 TM9 and S. typhimurium TA 98, which are reverted by base substitution and frame-shift mutagens, respectively. Similarly to the reference compound, all ellipticine analogues appeared to be no mutagenic. The obtained results suggest that they induce the antiproliferative activity in mammalian cells mainly as topoisomerase inhibitors, similarly to ellipticine itself. Therefore, they represent an interesting model to design new potential anticancer drugs.
- Grazia Ferlin,Chiarelotto,Baccichetti,Carlassare,Toniolo,Bordin
-
p. 1513 - 1528
(2007/10/02)
-
- Sulfonylhydrazines, metal complexes thereof, and solutions containing such compounds for use in extraction of metal values
-
Certain sulfonylhydrazines, metal complexes thereof and solutions of said compounds in essentially water-immiscible, liquid hydrocarbon solvents are disclosed. The sulfonylhydrazines have the general structural formula: wherein R and R1 are as defined in the specification and claims hereof. Particular metal values are recovered from their aqueous solutions by using sulfonylhydrazines dissolved in essentially water-immiscible, liquid hydrocarbon solvents. The extraction process involves contacting the metal value containing aqueous solution with the solution of the sulfonylhydrazines in essentially water-immiscible, liquid hydrocarbon solvent and stripping the metal from the loaded organic phase.
- -
-
-