Preparation and structure of oxo-rhenium(V) complexes with 7-azaindole

1993 ◽  
Vol 71 (12) ◽  
pp. 2060-2069 ◽  
Author(s):  
Anne-Marie Lebuis ◽  
André L. Beauchamp
Keyword(s):  
Hydrogen Bonds ◽  
Trans Isomer ◽  
Nmr Spectra ◽  
Binding Mode ◽  
Relative Orientation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxo Compounds ◽  
C Nmr

Four Re(V) oxo compounds were obtained from 7-azaindole (Haza) and ReOCl3(PPh3)2: the oxo-bridged dimer Re2O3Cl4(Haza)4 (1), the oxo–ethoxo monomers ReO(OEt)Cl2(Haza)2 (2) and ReO(OEt)Cl2(Haza)(PPh3) (3), and the dioxo [ReO2(Haza)4]Cl salt (4a). [ReO2(Haza)4]I (4b) was also prepared from ReO2I(PPh3)2. The ReO(OEt)Cl2(Haza)2 complex was shown by X-ray diffraction (C2/c, a = 16.292, b = 9.395, c = 12.104 Å, β = 101.47°, R = 0.041) to consist of individual molecules of the trans-trans isomer in which azaindole is N7-bonded. Crystals of [Formula: see text] (C2/m a = 15.422, b = 13.055, c = 9.086 Å, β = 91.13°, R = 0.059) contain well separated Cl− anions and trans-dioxo cations. The N7-bonded azaindole ligands are held parallel to the O=Re=O direction by intramolecular [Formula: see text] hydrogen bonds, but the relative orientation of the four ligands cannot be determined because of disorder. Characteristic Re—oxygen vibrations are observed in infrared for each type of compounds. The 1H and 13C NMR spectra are discussed in relation with the azaindole binding mode.

Preparation and Crystal Structure of Genistein Benzenesulfonate Prodrugs

2008 ◽  
Vol 2008 (10) ◽  
pp. 555-558 ◽  
Author(s):  
You Peng ◽  
Zeyuan Deng ◽  
Shaojie Lang ◽  
Yawei Fan
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Sulfonic Acid ◽  
Nmr Spectra ◽  
High Yield ◽  
X Ray Diffraction ◽  
Aromatic Rings ◽  
X Ray ◽  
H Nmr ◽  
Ester Prodrugs

In order to improve bioavailability and anticancer activity of genistein, a series of novel sulfonic acid ester prodrugs of the isoflavone genistein were synthesised in high yield with excellent regioselectivity. Their structures were characterised by IR, MS, elemental analysis and 1H NMR spectra. The crystal structure was examined by X-ray diffraction. X-ray structure determination revealed that all the aromatic rings in the compound are not coplanar. In the crystal structure, molecules are linked through intermolecular C-H···O hydrogen bonds, forming layers parallel to the ab plane.

Article

1999 ◽  
Vol 77 (5-6) ◽  
pp. 1057-1065
Author(s):  
John T Edward ◽  
Francis L Chubb ◽  
Denis FR Gilson ◽  
Rosemary C Hynes ◽  
Françoise Sauriol ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Acidic Solution ◽  
Variable Temperature ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
Cage Compounds ◽  
Amine Nitrogen ◽  
X Ray ◽  
Bridgehead Nitrogen ◽  
C Nmr

Three new cage peroxides, 1,6-diaza-3,4,8,9-tetraoxabicyclo[4.4.2]dodecane (3a),1,6-diaza-3,4,8,9-tetraoxa-11-methylbicyclo[4.4.2]dodecane (3b), and 1,6-diaza-3,4,8,9-tetraoxatricyclo[4.4.2.411,12]hexadecane (4), have been prepared by reaction of 1,2-diaminoethane, 1,2-diaminopropane, and trans-1,2-diaminocyclohexane, respectively, with formaldehyde and hydrogen peroxide in aqueous acidic solution. Their structures have been established by X-ray diffraction, and show the bridgehead nitrogen atoms to be predominantly sp2 hybridized. The structures accord with 1H and 13C NMR spectra. Variable temperature NMR studies show that the diperoxide 3a begins to undergo rapid inversion (on the NMR time scale) at about 303 K; up to 370 K the diperoxides 3b and 4 show no conformational change.Key words: cage compounds, formaldehyde, peroxides, amine nitrogen, hybridization.

Interactions de l'ion Ag+ avec la glutarimide

1984 ◽  
Vol 62 (7) ◽  
pp. 1287-1291 ◽  
Author(s):  
Johanne Perron ◽  
André L. Beauchamp
Keyword(s):  
Infrared Spectroscopy ◽  
Infrared Spectrum ◽  
Nmr Spectra ◽  
The Other ◽  
Mirror Plane ◽  
Bond Orders ◽  
X Ray Diffraction ◽  
Complex Species ◽  
X Ray ◽  
C Nmr

The 1:1 complex formed between Ag+ ions and glutarimide was investigated by X-ray diffraction, infrared spectroscopy, and 1H and 13C nmr. The crystals are monoclinic, C2/c, a = 13.497(3) Å, b = 9.503(2) Å, c = 9.600(4) Å, β = 92.30(3)°, Z = 4 molecules per cell. The structure was refined on 1086 nonzero [Formula: see text] reflections to R = 0.027. One half of the Ag atoms are linearly coordinated to the N atoms of two deprotonated glutarimide ligands, whereas the other half are surrounded by an approximate tetrahedron of four carbonyl oxygens belonging to two adjacent [Glu–Ag–Glu]− units. The [Glu–Ag–Glu]− groups are joined by tetrahedrally coordinated Ag atoms into infinite chains along the c axis. Complexation introduces a number of changes in the infrared spectrum of glutarimide. They can be related to the disappearance of the N—H vibrator and the change of bond orders in the —C(O)—N—C(O)— portion of the ligand. The nmr spectra show that coordinated glutarimide retains a mirror plane when the Ag complex is dissolved in DMSO. This suggests that the O-bonded Ag atoms dissociate to a large extent in solution, leaving the linear [Glu–Ag–Glu]− ions as the major glutarimide complex species.

scholarly journals Palladium(II) complexes with R2edda derived ligands, Part III: Diisobutyl (s,s)-2,2'-(1,2-ethanediyldiimino)di(4-methylpentanoate) and its palladium(II) complex: Synthesis and characterization

2009 ◽  
Vol 74 (11) ◽  
pp. 1249-1258 ◽  
Author(s):  
Bojana Zmejkovski ◽  
Goran Kaludjerovic ◽  
Santiago Gómez-Ruiz ◽  
Tibor Sabo
Keyword(s):  
Crystal Structure ◽  
Nmr Spectroscopy ◽  
Hydrogen Bonds ◽  
Nmr Spectra ◽  
Symmetry Axis ◽  
Layer Structure ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ir And Nmr Spectroscopy

A new R2edda-type ester, diisobutyl (S,S)-2,2'-(1,2-ethane-diyldiimino) di(4-methylpentanoate) dihydrochloride, [(S,S)-H2iBu2eddl]Cl2, 1, and its palladium(II) complex, dichloro(diisobutyl (S,S)-2,2'-(1,2-ethanediyldiimino) di(4-methylpentanoate))palladium(II), [PdCl2{(S,S)-iBu2eddl}], 2, were synthesized and characterized by elemental analysis, as well as IR and NMR spectroscopy. It was found that complex 2 was obtained as mixture of two diastereoisomers, observed in NMR spectra. The crystal structure of compound 1 was determined by X-ray diffraction studies and is described. The isolated crystals consisted of one dicationic species [(S,S)-H2iBu2eddl]2+ and two Cl-. The crystal system was tetragonal with the space group P42. Hydrogen bonds significant for the manner of packing are N-H1N???Cl, 3.049(3) ?, 159(3)? and N-H2N???Cl, 3.100(3) ?, 164(3)?. An infinite chain was formed building a one layer structure, usual for these types of compounds. The C2 symmetry axis of the compound passes through the C1-C1i bond vector and lies perpendicular to the plane N2Cl2.

Synthesis and crystal structures of a 3-acetylated (20S,24S)-ocotillol-type saponin and its C-24 epimer

2017 ◽  
Vol 73 (6) ◽  
pp. 464-469 ◽  
Author(s):  
Juan Liu ◽  
Yang-Rong Xu ◽  
Xing-Si An ◽  
Gui-Ge Hou ◽  
Qing-Guo Meng
Keyword(s):  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Dimensional Network ◽  
Crystal Packings ◽  
C Nmr

In order to study the in vivo protective effect on myocardial ischemia, (20S,24R)-epoxydammarane-12β,25-diol, (V), and (20S,24S)-epoxydammarane-12β,25-diol, (VI), were synthesized through a novel synthetic route. Two key intermediates, namely (20S,24R)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, (III) [obtained as the hemihydrate, C32H54O5·0.5H2O, (IIIa), and the ethanol hemisolvate, C32H54O5·0.5C2H5OH, (IIIb), with identical conformations but different crystal packings], and (20S,24S)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, C32H54O5, (IV), were obtained during the synthesis. The structures were confirmed by 1H NMR, 13C NMR and HRMS analyses, and single-crystal X-ray diffraction. Molecules of (IIIa) are extended into a two-dimensional network constructed with water molecules linked alternately through intermolecular O—H...O hydrogen bonds, which are further stacked into a three-dimensional network. Compound (IIIb) contains two completely asymmetric molecules, which are linked in a disordered manner through intermolecular C—H...O hydrogen bonds. While the crystal stacks in compound (IV) are linked via weak C—H...O hydrogen bonds, the hydrogen-bonded chains extend helically along the crystallographic b axis.

Partial Reduction of the N–O Functions of Partially Deprotonated Bis(hydroxylamine) Complexes

2009 ◽  
Vol 64 (10) ◽  
pp. 1208-1212
Author(s):  
Patrick Bösing ◽  
Hans-Georg Stammler ◽  
Norbert W. Mitzel
Keyword(s):  
Nmr Spectroscopy ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Elemental Analysis ◽  
Titanium Tetrachloride ◽  
Partial Reduction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amine Function ◽  
C Nmr

The reduction of a partially deprotonated bishydroxylamine complex {(tBu2Ga)2[cyclo-ON(Me)(CH2)2- (Me)NO][HON(Me)(CH2)2(Me)(H)NO]} with a reagent composed of titanium tetrachloride and methyllithium leads to the reduction of one of the N-O groups to an amine function affording the salt {(tBu2Ga)[cyclo- ON(H)(Me)(CH2)2NHMe]}+ {tBu2GaCl2}−. This has been characterised by 1H and 13C NMR spectroscopy, by elemental analysis and by single crystal X-ray diffraction, showing the neutral amine/hydroxylamine ligand to be present in its tautomeric aminoxide form. The molecules form hexameric cyclic aggregates by N-H···Cl hydrogen bonds.

Synthesis and Crystal Structure of 17-Allyl-4,5-anhydro-7α-[(R)-1-hydroxy-1-methyl-3-(2-thienyl)propyl]-6-methoxy-6,14-ethanomorphinan-3,4,5-triol

2005 ◽  
Vol 70 (2) ◽  
pp. 237-246
Author(s):  
He Liu ◽  
Jingyan Wang ◽  
Bohua Zhong
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Nmr Spectra ◽  
Chain Structure ◽  
Equatorial Position ◽  
Dimensional Chain ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
One Dimensional ◽  
X Ray

17-Allyl-4,5-anhydro-7α-[(R)-1-hydroxy-1-methyl-3-(2-thienyl)propyl]-6-methoxy-6,14-ethanomorphinan-3,4,5-triol (thienorphine 6) was synthesized and structurally characterized by NMR spectra, ESI-MS and X-ray diffraction. The crystal structure indicates that thienorphine maintained the main rigid structure of morphine while containing the C6-C14 ethano bridge. The allyl group is located in the equatorial position as expected. The packing diagram of 6 showed the presence of intramolecular and intermolecular O-H···O hydrogen bonds linking the molecules into a zigzag infinite quasi-one-dimensional chain structure.

scholarly journals Sessilifol A and B, Urease Inhibitory Pimarane-type Diterpenes from Hymenocrater sessilifolius

2017 ◽  
Vol 12 (12) ◽  
pp. 1934578X1701201
Author(s):  
Sadia Khan ◽  
Muhammad Shaiq Ali ◽  
Zeeshan Ahmed ◽  
Mehreen Lateef ◽  
Sammer Yousuf ◽  
...  
Keyword(s):  
Single Crystal ◽  
Vanillic Acid ◽  
Nmr Spectra ◽  
Soluble Fraction ◽  
2D Nmr ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inhibitory Potential ◽  
Urease Inhibitory ◽  
C Nmr

New pimarane type diterpenes named sessilifol A (1) and B (2) have been isolated from the EtOH soluble fraction of Hymenocrater sessilifolius Benth., along with eight known constituents cirsimaritin (3), gardenin C (4), β-sitosterol (5), saringosterol (6), β-sitosterol glucoside (7), ursolic acid (8), sucrose (9) and vanillic acid (10). Their structures were elucidated on the basis of 1H- and 13C-NMR spectra and by 2D-NMR experiments. The structure of 1 was further confirmed by single crystal X-ray diffraction technique. The compound 2 showed potent inhibitory potential against the enzyme urease while 1, 3, 4 and 10 were moderately active.

Characterization of the ionic clathrate hydrate of tetra-n-butylammonium acrylate

2015 ◽  
Vol 93 (9) ◽  
pp. 954-959 ◽  
Author(s):  
Sanehiro Muromachi ◽  
Masato Kida ◽  
Satoshi Takeya ◽  
Yoshitaka Yamamoto ◽  
Ryo Ohmura
Keyword(s):  
Nmr Spectra ◽  
Clathrate Hydrate ◽  
Unit Cell ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lattice Water ◽  
C Nmr ◽  
The Ideal

The ionic clathrate hydrate of tetra-n-butylammonium (TBA) acrylate was characterized using single-crystal X-ray diffraction, elemental analysis, and nuclear magnetic resonance (NMR) spectroscopy. The crystal structure of TBA acrylate was Jeffrey’s type III and tetragonal P42/n, with a 33.076(7) × 33.076(7) × 12.170(2) Å3 unit cell. The volume of the unit cell was 13315(5) Å3, which is almost twice that of the ideal structure. The TBA cation was disordered and located in two types of fused cages. Although the acrylate anion was located in a pentagonal dodecahedral cage neighboring the TBA cation, there is a residual acrylate anion that could be around the other TBA cation in the unit cell. Solid-state 13C NMR spectra showed that the TBA cation was clearly disordered at 173 K, but not at 239 K. NMR peaks from the acrylate anion were not observed at either temperature. This is probably because of the strong restriction on the acrylate anion by hydrogen bonding with the lattice water. Some of the characteristics of the anion and cation of the ionic guest incorporated in the hydrate structure have yet to be defined. Further research is needed to clarify complexation of the ionic clathrate hydrate and the ionic guest, and the resulting structure.

The interaction of D-penicillamine with aldehydes and ketones: 2-phenyl-5,5-dimethylthiazolidine-4-carboxylic acid

1994 ◽  
Vol 72 (7) ◽  
pp. 1621-1624 ◽  
Author(s):  
R.A. Bell ◽  
J.F. Britten ◽  
H.E. Howard-Lock ◽  
C.J.L. Lock ◽  
M. Schmidt
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Nmr Spectra ◽  
Room Temperature ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aldehydes And Ketones ◽  
Thiazolidine Ring ◽  
C Nmr

The reaction of D-penicillamine and benzaldehyde yielded 2-phenyl-5,5-dimethylthiazolidine-4-carboxylic acid. The structure was determined by single crystal X-ray diffraction. Crystals were monoclinic, P21, a = 9.785(2), b = 6.941(1), c = 10.399(2) Å, β = 114.06(3)°, Z = 2. Intensities were measured on a Rigaku AFC6R diffractometer with Cu Kα radiation and 1881 reflections were used to determine the structure. R = 0.076, wR = 0.048. The compound exists as an amino acid in the 2S,4S configuration. The conformation of the thiazolidine ring is determined by intermolecular hydrogen bonding. Bond lengths and angles are normal. 1H and 13C NMR spectra showed that epimerization takes place in d4-CH3OH solution, and the ratio of 2S,4S diastereomer to 2R,4S diastereomer at room temperature is 65:35.

Sign in / Sign up

Export Citation Format

Share Document