A new non-azole inhibitor of ABA 8′-hydroxylase: Effect of the hydroxyl group substituted for geminal methyl groups in the six-membered ring

2006 ◽  
Vol 16 (12) ◽  
pp. 3302-3305 ◽  
Author(s):  
Yoshiharu Araki ◽  
Arisa Miyawaki ◽  
Tomoyuki Miyashita ◽  
Masaharu Mizutani ◽  
Nobuhiro Hirai ◽  
...  
Keyword(s):  
Membered Ring ◽  
Hydroxyl Group ◽  
Methyl Groups

A New Non-Azole Inhibitor of ABA 8′-Hydroxylase: Effect of the Hydroxyl Group Substituted for Geminal Methyl Groups in the Six-Membered Ring.

ChemInform ◽  
2006 ◽  
Vol 37 (38) ◽  
Author(s):  
Yoshiharu Araki ◽  
Arisa Miyawaki ◽  
Tomoyuki Miyashita ◽  
Masaharu Mizutani ◽  
Nobuhiro Hirai ◽  
...  
Keyword(s):  
Membered Ring ◽  
Hydroxyl Group ◽  
Methyl Groups

Synthesis, crystal structure and molecular conformation of (±)-1-oxoferruginol and (±)-shonanol

2004 ◽  
Vol 219 (10) ◽  
Author(s):  
Swastik Mondal ◽  
Monika Mukherjee ◽  
Arnab Roy ◽  
Debabrata Mukherjee
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Diffraction Data ◽  
Molecular Conformation ◽  
Membered Ring ◽  
Methyl Groups ◽  
Single Bond ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Structures

Abstract(±)-1-oxoferruginol and (±)-shonanol, two potential intermediates in the synthesis of tricyclic diterpenoid ferruginol, have been prepared and crystal structures of the compounds have been investigated using single-crystal X-ray diffraction data. The methyl groups of the isopropyl moiety in (±)-shonanol are disordered over two positions with occupation factors 0.65(1) and 0.35(1), respectively. Although the chemical structures of two compounds are very similar, a C—C single bond in the terminal six-membered ring of (±)-1-oxoferruginol is replaced by a C=C bond in (±)-shonanol, the quantitative isostructurality index calculations indicate that the structures are not isostructural. Intermolecular O—H…O hydrogen bonds between pairs of molecules in the compounds related by center of inversion lead to characteristic dimers forming R

A 51V NMR investigation of the interactions of aqueous vanadate with hydroxylamine

1997 ◽  
Vol 75 (7) ◽  
pp. 1002-1010 ◽  
Author(s):  
Sarah J. Angus-Dunne ◽  
Pradip C. Paul ◽  
Alan S. Tracey
Keyword(s):  
Chemical Shifts ◽  
Formation Constants ◽  
Hydroxyl Group ◽  
Methyl Groups ◽  
Trigonal Bipyramidal ◽  
Anionic Complexes ◽  
Acidic Conditions ◽  
A Charge ◽  
Neutral Conditions ◽  
Lower Ligand

The aqueous reactions of hydroxylamine and N-methylhydroxylamine with vanadate have been studied. Ligand, vanadium, and proton stoichiometries of the products have been obtained as have their formation constants. At lower ligand concentrations the predominant complex contains a single hydroxamido ligand and this has been assigned a five-coordinate, tetrahedral-like structure where the hydroxamido group is coordinated in a side-on fashion. Four bishydroxamido products were observed. These four complexes consisted of two distinct groups of two isomeric complexes each and have been assigned six-coordinate (tetrahedral-like) and seven-coordinate (trigonal bipyramidal-like) geometries. For the N-methylhydroxamido ligand, 10 bisligand products in 2 groups of 5 isomers each were observed. The additional products over the hydroxylamine situation arise from the relative orientations of the ligand methyl groups. For both ligands, the monoligand products carried a single negative charge and did not have a pKa, within the range of about 6–10. The bisligand products did not carry a charge under neutral conditions. The tetrahedral bisligand products could be protonated under acidic conditions (pKa ~ 6.6) but could not be deprotonated. In contrast, the trigonal bipyramidal products were not protonated under acidic conditions but could give up a proton under basic conditions (pKa ~ 7.4) to form anionic complexes. The relative orientations of the ligands and also the number of methyl groups and their relative orientations in the complex have a significant influence on the 51V chemical shifts. One additional complex was observed to form and was assigned to an ester-like product formed by reaction at the hydroxyl group. Keywords: vanadate, complexes, hydroxylamine, methylhydroxylamine, peroxovanadate.

Theoretical studies of model compounds of lathyrane-type diterpenes

2004 ◽  
Vol 82 (1) ◽  
pp. 11-18 ◽  
Author(s):  
Yukimasa Terada ◽  
Tomoo Matsuura ◽  
Yukari Mori ◽  
Shosuke Yamamura
Keyword(s):  
Ab Initio ◽  
Molecular Mechanics ◽  
Molecular Orbital ◽  
Theoretical Calculations ◽  
Membered Ring ◽  
Orbital Method ◽  
Methyl Groups ◽  
Molecular Orbital Method ◽  
Stable Conformation ◽  
Semi Empirical

The conformation of the 11-membered ring of the lathyrane skeleton has been investigated using NMR spectra and theoretical calculations. Some other skeletons, such as jatrophane, jatrapholane, and tigliane, seem to be derived from this framework, and the conformation is important in connection with the configuration of the resultant diterpenes. The conformation of lathyrane is principally defined by the orientation of the two methyl groups; namely, the methyl groups on C1 and C6 directed above or below the ring plane. Theoretical calculations revealed that the predominant conformation is altered depending on the oxygen functional groups on the ring. As far as the bond lengths, bond angles, and dihedral angles are concerned, all calculation methods afforded reasonable results. In contrast, as regards conformational stability, only the ab initio molecular orbital method (RHF/6-31G*) predicted the most stable conformation, consistent with NOE experiments. On the other hand, the stable conformations predicted by the ab initio method (RHF/STO-3G), the semi-empirical molecular orbital method (MOPAC(PM3)), and the molecular mechanics calculations (MM3) did not necessarily agree with the conformers suggested by the NOE experiments.Key words: ab initio MO, semi-empirical MO, molecular mechanics, 11-membered ring conformation, NOE.

tert-Butyl 3-endo-3-hydroxy-8-azabicyclo[3.2.1]octane-8-carboxylate

2006 ◽  
Vol 62 (4) ◽  
pp. o1233-o1234
Author(s):  
Shuang-Wei Chen ◽  
Cai-Hong Xu ◽  
Guo-Rong Zheng ◽  
Xu-Hu Jin
Keyword(s):  
Dopamine Transporter ◽  
Title Compound ◽  
Chair Conformation ◽  
Membered Ring ◽  
Hydroxyl Group ◽  
Tert Butyl ◽  
Envelope Conformation ◽  
Compound C ◽  
Important Intermediate

The title compound, C12H21NO3, is an important intermediate for new dopamine transporter inhibitors. The six-membered ring of the azabicyclo[3.2.1]octane system adopts a chair conformation with the hydroxyl group axial. The fused five-membered ring is in an envelope conformation.

2,4-Dibenzoyl-3,5-bis(4-methoxylphenyl)-1-phenylcyclohexanol

2006 ◽  
Vol 62 (4) ◽  
pp. o1631-o1632 ◽  
Author(s):  
Xinxiang Luo ◽  
Zixing Shan
Keyword(s):  
Hydrogen Bonding ◽  
Title Compound ◽  
Chair Conformation ◽  
Membered Ring ◽  
Hydroxyl Group ◽  
Intermolecular Hydrogen Bonding ◽  
Compound C

The title compound, C40H36O5, was synthesized from p-anisaldehyde and acetophenone. The central six-membered ring adopts a chair conformation and most of the bulky side groups are located in equatorial positions. The hydroxyl group is involved in weak intra- and intermolecular hydrogen bonding.

scholarly journals Neutralization of solvent vapors of brand 646 by the adsorption-catalytic method

2021 ◽  
pp. 130-136
Author(s):  
A. S. Panasyugin ◽  
N. P. Masherova ◽  
A. R. Tsyganov ◽  
N. D. Pavlovsky
Keyword(s):  
Mixed Solvent ◽  
Synthetic Zeolite ◽  
Hydroxyl Group ◽  
Methyl Groups ◽  
Organic Substances ◽  
Benzene Derivatives ◽  
Foam Material ◽  
Catalytic Method ◽  
Sorption Volume ◽  
Solvent Vapors

The aim of the paper is investigation of neutralization of solvent vapors of the brand 646 by an adsorption-catalytic method. The adsorption-catalytic method includes the following stages: adsorption of the solvent components by adsorbent, thermal desorption and periodic flameless catalytic oxidation of organic substances to carbon dioxide and water. Synthetic zeolite of the NaX brand was used as a sorbent, catalyst was porous Al2O3/SiO2 ceramic foam material with an active catalytic phase. Solvent contains aceton, toluene, butylacetate, ethanol, ethyl cellosolve, n-butanol. It is shown that the value of the sorption volume of zeolite for each class of compounds depends on the certain factors: the length and structure of the carbon skeleton, the position of the hydroxyl group (for alcohols and esters), number of methyl groups in the molecules (for benzene derivatives). The conversion of the mixed solvent components was 65.4–90.1 %.

The Crystal and Molecular Structures of the 3,5-Dimethylpyrazolylgallium dimethyl dimer, [Me2Ga·N2C5H7]2, and the Hydroxy-bridged Species, [Me2Ga(OH)(N2C5H7)GaMe2·2N2C5H8]

1975 ◽  
Vol 53 (19) ◽  
pp. 2944-2954 ◽  
Author(s):  
David F. Rendle ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Least Squares ◽  
Membered Ring ◽  
Molecular Structures ◽  
Methyl Groups ◽  
Central Feature ◽  
Fourier Methods ◽  
Full Matrix ◽  
Space Group ◽  
Crystal And Molecular Structures ◽  
The Mean

Crystals of the 3,5-dimethylpyrazolylgallium dimethyl dimer [Me2Ga·N2C5H7]2 (1a) are monoclinic, a = 8.660(3), b = 13.776(1), c = 8.443(2) Å, β = 112.45(2)°, Z = 2, space group P21/c, and crystals of the hydroxy-bridged species [Me2Ga(OH)(N2C5H7)GaMe2·2N2C5H8] (1b) are monoclinic, a = 28.778(3), b = 9.098(3), c = 20.222(2) Å, β = 100.72(1)°, Z = 8, space group C2/c. Both structures were solved by Patterson and Fourier methods and were refined by full-matrix least-squares methods to final R values of 0.071 and 0.045 for 1443 and 2746 reflections with I ≥ 3σ(I) respectively. Molecules of 1a lie on crystallographic centers of symmetry, the central Ga—(N—N)2—Ga ring being almost planar as a result of steric interactions between gallium-methyl groups and those on the 'pyrazolyl' rings. The mean Ga—N and Ga—C distances are 1.993 Å and 1.962 Å respectively. Compound 1b was formed by the attack of moisture on the strained dimer 1a. The central feature is a five-membered Ga2N2O ring, with two 3,5-dimethylpyrazoie molecules hydrogen-bonded to it (N—H … O, O—H … N, 2.851 and 2.892 Å) and to each other (N—H … N, 2.907 Å). The five-membered ring adopts a slightly distorted envelope conformation, the angle between the Ga2N2 and N2O moieties being 13.9°. The mean Ga—N and Ga—O distances are 1.989 and 1.934 Å respectively.

Mass Spectra of Spirobenzylisoquinoline Alkaloids

1971 ◽  
Vol 49 (18) ◽  
pp. 3025-3037 ◽  
Author(s):  
C. K. Yu ◽  
D. B. MacLean
Keyword(s):  
Carbonyl Group ◽  
Mass Spectra ◽  
Major Ions ◽  
Membered Ring ◽  
Hydroxyl Group ◽  
Model Compounds ◽  
Fragmentation Mechanisms

The mass spectra of a number of spirobenzylisoquinoline alkaloids, several of their derivatives, and some model compounds are recorded and discussed. Fragmentation mechanisms are proposed for the formation of the major ions in the spectra of compounds containing one and two oxygen functions in the five-membered ring. The spectra of compounds containing a carbonyl group differ markedly from those having a hydroxyl group in the five-membered ring. Several model compounds were synthesized and characterized and their spectra compared with those of the alkaloids.

Preparation of C(18)-empiric 20,29,30-trinorlupane derivatives. 1H, 13C NMR and mass spectra

1986 ◽  
Vol 51 (3) ◽  
pp. 621-635 ◽  
Author(s):  
Václav Křeček ◽  
Jiří Protiva ◽  
Miloš Buděšínský ◽  
Eva Klinotová ◽  
Alois Vystrčil
Keyword(s):  
Nitrous Acid ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Allylic Oxidation ◽  
Hydroxyl Group ◽  
Methyl Groups ◽  
Unsaturated Ketone ◽  
H Nmr ◽  
C Nmr

Reaction of amide I with nitrous acid gave the olefins II, III and IV. On allylic oxidation of olefin IV α,β-unsaturated ketone V is formed from which olefins VIII and IX were prepared by a sequence of further reactions. Addition of hydrogen to the double bond of olefin IV and α,β-unsaturated ketone V takes place on catalytic hydrogenation from the β-side and leads to derivatives with cis-annellated rings D/E. This made the preparation of hydrocarbons VI and VII epimeric on C(18) possible, which represent reference compounds for the study of the effect of substituents on the chemical shifts of the methyl groups and the saturated carbon atoms of 18αH and 18βH-lupane derivatives. The configuration of the hydroxyl group in epimers XI and XII were derived from 1H NMR spectra. Deuteration of olefins III, IV and IX gave deuteriohydrocarbons XVI to XVIII. The 1H, 13C NMR and mass spectra of the substances prepared are discussed.

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