scholarly journals X-Ray Molecular and Crystal Structure of Imidazolopyrroloquinoline, a Main Reaction Product of Pyrroloquinolinequinone (PQQ) and L-Tryptophan in Vitro.

1996 ◽  
Vol 44 (7) ◽  
pp. 1387-1390 ◽  
Author(s):  
Toshimasa ISHIDA ◽  
Yasuko IN ◽  
Eiji KAWAMOTO ◽  
Takashi AMANO ◽  
Jyutoku KANAYAMA ◽  
...  
1981 ◽  
Vol 36 (10) ◽  
pp. 1208-1210 ◽  
Author(s):  
Hartmut Köpf ◽  
Joachim Pickardt

Abstract The molecular structure of the bridged [1]-titanocenophane 1,1'-dimethylsilylene titanocene dichloride, (CH3)2Si(C5H4)2TiCl2, has been investigated by an X-ray structure determination. Crystal data: monoclinic, space group C2/c, Z = 4, a = 1332.9(3), 6 = 988.7(3), c = 1068.9(3) pm, β = 113.43(2)°. The results are compared with the structural dimensions of similar compounds: 1,1'-methylene titanocene dichloride, CH2(C5H4)TiCl2, with the unbridged titanocene dichloride, (C5H5)2TiCl2 and the ethylene-bridged compound (CH2)2(C5H4)2TiCl2


1986 ◽  
Vol 250 (2) ◽  
pp. F302-F307 ◽  
Author(s):  
J. M. Burnell ◽  
C. Liu ◽  
A. G. Miller ◽  
E. Teubner

To study the effects of bicarbonate and magnesium on bone, mild acidosis and/or hypermagnesemia were produced in growing rats by feeding ammonium chloride and/or magnesium sulfate. Bone composition, quantitative histomorphometry, and mineral x-ray diffraction (XRD) characteristics were measured after 6 wk of treatment. The results demonstrated that both acidosis (decreased HCO3) and hypermagnesemia inhibited periosteal bone formation, and, when combined, results were summative; and the previously observed in vitro role of HCO3- and Mg2+ as inhibitors of crystal growth were confirmed in vivo. XRD measurements demonstrated that decreased plasma HCO3 resulted in larger crystals and increased Mg resulted in smaller crystals. However, the combined XRD effects of acidosis and hypermagnesemia resembled acidosis alone. It is postulated that the final composition and crystal structure of bone are strongly influenced by HCO3- and Mg2+, and the effects are mediated by the combined influence on both osteoblastic bone formation and the growth of hydroxyapatite.


mBio ◽  
2018 ◽  
Vol 9 (6) ◽  
Author(s):  
Pradeep Kumar ◽  
Glenn C. Capodagli ◽  
Divya Awasthi ◽  
Riju Shrestha ◽  
Karishma Maharaja ◽  
...  

ABSTRACTWe report GSK3011724A (DG167) as a binary inhibitor of β-ketoacyl-ACP synthase (KasA) inMycobacterium tuberculosis. Genetic and biochemical studies established KasA as the primary target. The X-ray crystal structure of the KasA-DG167 complex refined to 2.0-Å resolution revealed two interacting DG167 molecules occupying nonidentical sites in the substrate-binding channel of KasA. The binding affinities of KasA to DG167 and its analog, 5g, which binds only once in the substrate-binding channel, were determined, along with the KasA-5g X-ray crystal structure. DG167 strongly augmented thein vitroactivity of isoniazid (INH), leading to synergistic lethality, and also synergized in an acute mouse model ofM. tuberculosisinfection. Synergistic lethality correlated with a unique transcriptional signature, including upregulation of oxidoreductases and downregulation of molecular chaperones. The lead structure-activity relationships (SAR), pharmacokinetic profile, and detailed interactions with the KasA protein that we describe may be applied to evolve a next-generation therapeutic strategy for tuberculosis (TB).IMPORTANCECell wall biosynthesis inhibitors have proven highly effective for treating tuberculosis (TB). We discovered and validated members of the indazole sulfonamide class of small molecules as inhibitors ofMycobacterium tuberculosisKasA—a key component for biosynthesis of the mycolic acid layer of the bacterium’s cell wall and the same pathway as that inhibited by the first-line antitubercular drug isoniazid (INH). One lead compound, DG167, demonstrated synergistic lethality in combination with INH and a transcriptional pattern consistent with bactericidality and loss of persisters. Our results also detail a novel dual-binding mechanism for this compound as well as substantial structure-activity relationships (SAR) that may help in lead optimization activities. Together, these results suggest that KasA inhibition, specifically, that shown by the DG167 series, may be developed into a potent therapy that can synergize with existing antituberculars.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Hatem A. Abdel-Aziz ◽  
Hazem A. Ghabbour ◽  
Wagdy M. Eldehna ◽  
Maha M. Qabeel ◽  
Hoong-Kun Fun

(Z)-N′-(2-Oxoindolin-3-ylidene)formohydrazide (2) was synthesized by the reaction of (Z)-3-hydrazonoindolin-2-one (1) with formic acid under reflux. The structure of2was characterized by IR, Mass,1H NMR, and X-ray crystal structure determination. Interestingly, compound2appeared in DMSO-d6ascisandtransamide rotomers in 25% and 75%, respectively. The X-ray analysis showed theZgeometrical isomer of2around –C=N– forcisandtransamide rotomers. The crystal of2belongs to monoclinic, space groupP21/c, witha=4.5206(1) Å,b=22.4747(7) Å,c=17.3637(5) Å,β=103.752(1)°,Z=8,V=1713.57(8) Å3,Dc=1.467 Mg m−3,μ=0.11 mm−1,F(000)=784,R=0.047, andwR=0.123for 3798 observed reflections withI>2σ(I). Compound2exhibited a moderate activity in its antimicrobial evaluation againstE. coliandP. aeruginosaand a good activity againstS. aureusclose to that of the standard drug ciprofloxacin. Thein vitroanticancer activity of2was evaluated against two human tumor cell lines, namely, HepG2 hepatocellular carcinoma and MCF-7 breast cancer. HepG2 cancer cell line was more susceptible to compound2than MCF-7.


1978 ◽  
Vol 33 (8) ◽  
pp. 838-842 ◽  
Author(s):  
H. J. Keller ◽  
W. Moroni ◽  
D. Nöthe ◽  
M. Scherz ◽  
J. Weiss

Oxidation of 5,10-dihydro-5,10-dimethylphenazine and 5,10-dihydro-5,10-diethyl-phenazine under different reaction conditions leads to several iodine containing solids. The preparation and X-ray structure of two of them, 5,10-dihydro-5,10-dimethyl-phcnaziniumtriiodide (3) and 5,10-dihydro-5,10-diethylphenaziniumtriiodido (4) are reported here.Compound 3 crystallizes in space group P21/n with lattice parameters a = 8.552(6) Å, b= 16.953(2) Å, c- 12.157(9) Å and β= 103.46(2)° with four formula units in the unit cell. The structure was refined to an R-value of 0.046 using 2387 independent reflections. The lattice constains distinct, slightly distorted triiodide ions and bent 5,10-dihydro-5,10-dimethylphenazinium radical cations. Compound 4 crystallizes in the same space group P21/n with lattice parameters a = 8.531(6) Å, b = 8.332(21) Å, c = 13.320(15) Å and β= 94.44(19)° with two formula units in the unit cell. The structure was refined to an R-value of 0.076 using 1195 independent reflections. The lattice contains strictly linear symmetrical triiodide ions and planar centrosymmetrical 5,10-dihydro-5,10-diethyl- phenazinium radical cations.


1977 ◽  
Vol 32 (1) ◽  
pp. 18-21 ◽  
Author(s):  
Manfred L. Ziegler ◽  
Bernd Nuber ◽  
Klaus Weidenhammer ◽  
Gerhard Hoch

The structure of [PCl4][VCl5] was determined from threedimensional X-ray data. The VCl5- ion is bipyramidal with almost C2v symmetry.


Sign in / Sign up

Export Citation Format

Share Document