Studies via X-ray analysis on intermolecular interactions and energy frameworks based on the effects of substituents of three 4-aryl-2-methyl-1H-imidazoles of different electronic nature and their in vitro antifungal evaluation

2018 ◽  
Vol 74 (11) ◽  
pp. 1447-1458 ◽  
Author(s):  
Mario A. Macías ◽  
Nerith-Rocio Elejalde ◽  
Estefanía Butassi ◽  
Susana Zacchino ◽  
Jaime Portilla
Keyword(s):  
Crystal Structure ◽  
Antifungal Activity ◽  
Crystal Structures ◽  
Intermolecular Interactions ◽  
Acid Base ◽  
Electronic Nature ◽  
Aryl Ring ◽  
X Ray ◽  
Base Properties

The crystal structures of 2-methyl-4-phenyl-1H-imidazole, C10H10N2, (3a), 4-(4-chlorophenyl)-2-methyl-1H-imidazole hemihydrate, C10H9ClN2·0.5H2O, (3b), and 4-(4-methoxyphenyl)-2-methyl-1H-imidazole, C11H12N2O, (3c), have been analyzed. It was found that the electron-donating/withdrawing tendency of the substituent groups in the aryl ring influence the acid–base properties of the 2-methylimidazole nucleus, changing the strength of the intermolecular N—H...N interactions. This behaviour not only influences the crystal structure but also seems to have an important effect on the antifungal activity. Considering the substituent groups, that is, H in (3a), Cl in (3b) and OMe in (3c), the formation of strong N—H...N connections has the probability (3a) > (3b) > (3c), while compound (3c) proves to be more active than (3a) and (3b) at all concentrations against C. neoformans.

scholarly journals Crystal structure of poly[[μ3-(S)-2-amino-3-hydroxypropanoato]-cis-di-μ-chlorido-caesiumpalladium(II)]

2017 ◽  
Vol 73 (12) ◽  
pp. 1898-1902
Author(s):  
Mohan Madhav Bhadbhade ◽  
Alexander J. Charlson
Keyword(s):  
Crystal Structure ◽  
Amino Acid ◽  
Antifungal Activity ◽  
Anticancer Activity ◽  
Crystal Structures ◽  
Title Compound ◽  
Coordination Environment ◽  
X Ray ◽  
Coordination Sites ◽  
Square Planar

The structure of the title compound, [CsPd(C3H6NO3)Cl2]n, previously shown to have anticancer activity in rodent test systems and recently found to have antifungal activity, has been determined. The Pd centre is in a square-planar coordination environment with two chlorine atoms incispositions and the remaining two coordination sites being coordinated by N and O atoms from deprotonated L-serine. Each of the Cs cations shows ninefold coordination with six chlorine and three O atoms resulting in a coordination environment that is similar to the well known Cs2SO4structure. X-ray crystal structures of only three dichloridopalladium(II)–amino acid complexes have been determined so far and the present paper describes one of those.

scholarly journals Crystal Chemical Relations in the Shchurovskyite Family: Synthesis and Crystal Structures of K2Cu[Cu3O]2(PO4)4 and K2.35Cu0.825[Cu3O]2(PO4)4

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 807
Author(s):  
Ilya V. Kornyakov ◽  
Sergey V. Krivovichev
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structural Complexity ◽  
Crystal Chemical ◽  
X Ray Diffraction ◽  
Complexity Measures ◽  
X Ray ◽  
The Family ◽  
Similarities And Differences ◽  
Related Compounds

Single crystals of two novel shchurovskyite-related compounds, K2Cu[Cu3O]2(PO4)4 (1) and K2.35Cu0.825[Cu3O]2(PO4)4 (2), were synthesized by crystallization from gaseous phase and structurally characterized using single-crystal X-ray diffraction analysis. The crystal structures of both compounds are based upon similar Cu-based layers, formed by rods of the [O2Cu6] dimers of oxocentered (OCu4) tetrahedra. The topologies of the layers show both similarities and differences from the shchurovskyite-type layers. The layers are connected in different fashions via additional Cu atoms located in the interlayer, in contrast to shchurovskyite, where the layers are linked by Ca2+ cations. The structures of the shchurovskyite family are characterized using information-based structural complexity measures, which demonstrate that the crystal structure of 1 is the simplest one, whereas that of 2 is the most complex in the family.

Effects of dietary alteration of bicarbonate and magnesium on rat bone

1986 ◽  
Vol 250 (2) ◽  
pp. F302-F307 ◽  
Author(s):  
J. M. Burnell ◽  
C. Liu ◽  
A. G. Miller ◽  
E. Teubner
Keyword(s):  
Crystal Structure ◽  
Bone Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Growing Rats ◽  
Final Composition ◽  
Rat Bone

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.

scholarly journals Crystal structures of two novel iron isocyanides from the reaction of 2,6-dimethylphenyl isocyanide, CNXyl, with bis(anthracene)ferrate(−1)

2022 ◽  
Vol 78 (1) ◽  
Author(s):  
William W. Brennessel ◽  
John E. Ellis
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Structures ◽  
Tridentate Ligand ◽  
Reductive Cyclization ◽  
X Ray Diffraction ◽  
X Ray

The reaction of the [K(18-crown-6)(thf)2]1+ (thf is tetrahydrofuran) salt of bis(anthracene)ferrate(−1), or [Fe(C14H10)2]−, with 2,6-dimethylphenyl isocyanide (CNXyl) in thf resulted in the formation of two new iron isocyanide complexes, namely, [(1,2,3,4-η)-anthracene]tris(2,6-dimethylphenyl isocyanide)iron, [Fe(C14H10)(C9H9N)3] or [Fe(1,2,3,4-η-C14H10)(CNXyl)3], and {5,6-bis(2,6-dimethylanilino)-3-(2,6-dimethylphenyl)-1,2,7-tris[(2,6-dimethylphenyl)imino]-3-azoniahept-3-ene-1,4,7-triido}tris(2,6-dimethylphenyl isocyanide)iron tetrahydrofuran disolvate, [Fe(C54H56N6)(C9H9N)3]·2C4H8O or [Fe(C54H56N6)(CNXyl)3]·2C4H8O, which were characterized by single-crystal X-ray diffraction. The former is likely an intermediate along the path to the known homoleptic [Fe(CNXyl)5], while the latter contains a tridentate ligand that is formed from the `coupling' of six CNXyl ligands. A third crystal structure from this reaction, (7-methylindol-1-ido-κN)(1,4,7,10,13,16-hexaoxacyclooctadecane-κ6 O)potassium, [K(C9H8N)(C12H24O6)] or [K(C9H8N)(18-crown-6)], contains a 7-methylindol-1-ide anion, in which one CNXyl ligand has shed a proton during its reductive cyclization.

scholarly journals Calixarene-mediated assembly of a small antifungal protein

IUCrJ ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 238-247 ◽  
Author(s):  
Jimi M. Alex ◽  
Martin L. Rennie ◽  
Sylvain Engilberge ◽  
Gábor Lehoczki ◽  
Hajdu Dorottya ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Antifungal Activity ◽  
High Resolution ◽  
Complex Formation ◽  
Binding Site ◽  
Crystal Structures ◽  
Protein Assembly ◽  
Bidentate Ligand ◽  
Antifungal Protein ◽  
Protein Recognition

Synthetic macrocycles such as calixarenes and cucurbiturils are increasingly applied as mediators of protein assembly and crystallization. The macrocycle can facilitate assembly by providing a surface on which two or more proteins bind simultaneously. This work explores the capacity of the sulfonato-calix[n]arene (sclx n ) series to effect crystallization of PAF, a small, cationic antifungal protein. Co-crystallization with sclx4, sclx6 or sclx8 led to high-resolution crystal structures. In the absence of sclx n , diffraction-quality crystals of PAF were not obtained. Interestingly, all three sclx n were bound to a similar patch on PAF. The largest and most flexible variant, sclx8, yielded a dimer of PAF. Complex formation was evident in solution via NMR and ITC experiments, showing more pronounced effects with increasing macrocycle size. In agreement with the crystal structure, the ITC data suggested that sclx8 acts as a bidentate ligand. The contributions of calixarene size/conformation to protein recognition and assembly are discussed. Finally, it is suggested that the conserved binding site for anionic calixarenes implicates this region of PAF in membrane binding, which is a prerequisite for antifungal activity.

Molekül- und Kristallstrukturen zweier einkerniger Ruthenium(II)-Komplexe mit dem starken π·Akzeptorliganden 2,2'-Azobis(pyridin) (abpy): [mer-Ru(abpy)3](PF6)2 und Ru(abpy)2Cl2 (ctc-Isomer) / Molecular and Crystal Structures of Two Mononuclear Ruthenium(II) Complexes with the Strongly π Accepting Ligand 2,2'-Azobis(pyridine) (abpy): [mer-Ru(abpy)3](PF6)2 and Ru(abpy)2Cl2 (ctc Isomer)

1995 ◽  
Vol 50 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Jörg Fees ◽  
H.-D. Hausen ◽  
Wolfgang Kaim
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Dihedral Angle ◽  
Intermolecular Interactions ◽  
Chelate Compound ◽  
Steric Repulsion ◽  
Structural Reorganization ◽  
Nitrogen Donor ◽  
Molecular And Crystal Structures ◽  
Halide Ligands

Crystal structure analyses of the title complexes have been carried out in order to establish their molecular configurations. The tris(chelate) complex dication in (1)(PF6)2 exhibits a mer configuration of pyridine and azo nitrogen atoms in an approximately octahedral arrangement at the metal. The dichlororuthenium bis(chelate) compound 2 has the halide ligands and the coordinated azo nitrogen centers in an equatorial cis arrangement whereas two pyridyl groups (one of each abpy ligand) occupy the axial positions. The bond distances from the metal to the nitrogen donor centers are systematically smaller for the stronger π accepting azo functions than for the more basic but less π acidic pyridyl groups, a result which differs from that obtained for Mo(0) and Cu(I) complexes of abpy. All Ru—N distances are shorter in the neutral dichloro complex 2. The non-coordinated pyridyl rings of the potentially tetradentate abpy ligands are tilted into approximate s-cis/(NN-trans)/s-trans positions (dihedral angle ω ≈ 145°) as to minimize steric repulsion, however, they do not coordinate to the metal (dRu-N > 327 pm). While there are no significant intermolecular interactions, the observed conformation implies that considerable structural reorganization is necessary for the formation of oligonuclear complexes.

scholarly journals E. S. Fedorov Promoting the Russian-German Scientific Interrelationship

Minerals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 181 ◽  
Author(s):  
Peter Paufler ◽  
Stanislav K. Filatov
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structure Analysis ◽  
Crystalline State ◽  
Crystal Structure Analysis ◽  
Present Knowledge ◽  
Personal Contact ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Impact

At the dawn of crystal structure analysis, the close personal contact between researchers in Russia and Germany, well documented in the “Zeitschrift für Krystallographie und Mineralogie”, contributed significantly to the evolution of our present knowledge of the crystalline state. The impact of the Russian crystallographer E. S. Fedorov upon German scientists such as A. Schoenflies and P. Groth and the effect of these contacts for Fedorov are highlighted hundred years after the death of the latter. A creative exchange of ideas paved the way for the analysis of crystal structures with the aid of X-ray diffraction.

scholarly journals Synthesis and X-ray Crystal Structures of Novel Spiro 1,3-benzoxazine Dimers

2002 ◽  
Vol 2002 (10) ◽  
pp. 473-474 ◽  
Author(s):  
H.Z. Alkhathlan ◽  
M.A. Al-Saad ◽  
H.M. Al-Hazimi ◽  
K.A. Al-Farhan ◽  
A.A. Mousa
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Mass Spectra ◽  
X Ray ◽  
New Compounds

Novel spiro 1,3-benzoxazine dimers are obtained when hydrazones of 2-hydroxyacetophenone are treated with triphosgene. An X-ray crystal structure, and the NMR and mass spectra of these new compounds, are reported and discussed.

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