Proton magnetic resonance and mass spectrometric studies on derivatives of sodium 2-O-α-D-mannopyranosyl-D-glycerate and related compounds

1969 ◽  
Vol 47 (21) ◽  
pp. 4083-4086 ◽  
Author(s):  
J. N. C. Whyte
Keyword(s):  
Magnetic Resonance ◽  
Methyl Ester ◽  
Proton Magnetic Resonance ◽  
Mass Spectra ◽  
Red Alga ◽  
Mass Spectrometric ◽  
Derivatives Of ◽  
Related Compounds

The proton magnetic resonance (p.m.r.) and mass spectra of the methyl ester pentaacetate of sodium 2-O-α-D-mannopyranosyl-D-glycerate from the red alga Rhodomela larix are compared to those of related compounds to affirm the assigned structure.

Pentafluorobenzyl Ester Derivatives of Nine Chlorophenoxy Acid Herbicides: Spectroscopic Properties and Utility for Identification Purposes

1978 ◽  
Vol 61 (5) ◽  
pp. 1140-1154
Author(s):  
Jacques O De Beer ◽  
Carlos H Van Peteghem ◽  
Aubin M Heyndrickx
Keyword(s):  
Magnetic Resonance ◽  
Human Urine ◽  
Proton Magnetic Resonance ◽  
Mass Spectra ◽  
Spectroscopic Properties ◽  
Urine Samples ◽  
Spectroscopic Techniques ◽  
Chlorophenoxy Acid Herbicides ◽  
Acid Herbicides ◽  
Derivatives Of

Abstract The pentafluorobenzyl esters of 9 chlorophenoxy acid herbicides were synthesized by the reaction of the acids with pentafluorobenzylbromide in alkaline acetone solution. Ultraviolet (UV), infrared (IR), proton magnetic resonance (PMR), and mass spectra (MS) were recorded. IR and mass spectra are shown and UV, PMR, and MS data are tabulated and discussed. A technique for extraction of the chlorophenoxy alkyl acid herbicides, followed by conversion to the corresponding pentafluorobenzyl esters, was developed for human urine samples. Applications in different concentration ranges (ppm, ppb) by different spectroscopic techniques (MS, IR) are demonstrated.

Conformational studies of some 5,9-dimethyl-6,7-benzomorphan diastereoisomers and related compounds

1969 ◽  
Vol 47 (19) ◽  
pp. 3623-3630 ◽  
Author(s):  
A. F. Casy ◽  
A. P. Parulkar
Keyword(s):  
Magnetic Resonance ◽  
Proton Magnetic Resonance ◽  
Piperidine Ring ◽  
Free Base ◽  
Conformational Studies ◽  
Related Compounds

The proton magnetic resonance characteristics of some α/β diastereoisomeric 5,9-dimethyl-6,7-benzomorphans are reported for free base, hydrohalide, and methiodide forms, and differences between α- and β-signals are interpreted in terms of the piperidine ring fragment of the β-salts adopting skew-boat conformations. The steric course of quaternization of benzomorphan isomers is discussed from results of alkylations using trideuteriomethyl iodide and other experiments. A possible correlation between conformational and potency differences in analgesically active benzomorphan diastereoisomers and related compounds is discussed.

The conformational preference and barrier to internal rotation of an equatorial 3,5-dichlorophenyl group by the J method. Derivatives of cyclohexane, 1,3-dithiane, 1,3-dioxane, and 1,3-dioxolane

1979 ◽  
Vol 57 (3) ◽  
pp. 355-359 ◽  
Author(s):  
Ted Schaefer ◽  
Walter Niemczura ◽  
Werner Danchura
Keyword(s):  
Magnetic Resonance ◽  
Molecular Mechanics ◽  
Internal Rotation ◽  
Phenyl Ring ◽  
Proton Magnetic Resonance ◽  
Conformational Preference ◽  
Molecular Mechanics Calculations ◽  
X Ray ◽  
Carbon Carbon Bond ◽  
Derivatives Of

We report the preparation and the analysis of the phenyl ring proton magnetic resonance spectra of 3,5-dichlorophenylcyclohexane and of the 2-(3,5-dichlorophenyl) derivatives of 1,3-dioxane, 1,3-dithiane, and 1,3-dioxolane. With the exception of the dioxolanes these compounds exist predominantly as the equatorial isomers. The J method is used to show that the phenyl moiety prefers the conformation in which the α C—H bond lies in the phenyl plane. The predominantly twofold barriers to rotation about the carbon–carbon bond between the two ring systems are 2.0 ± 0.3, 0.4 ± 0.2, 2.2 ± 0.3, 0.85 ± 0.3 kcal/mol for these compounds, in the order given above. The low value for the barrier in the 1,3-dioxane derivative agrees reasonably well with molecular mechanics calculations and with the results of calorimetric and X-ray studies on equatorial 2-phenyl-1,3-dioxane.

ChemInform Abstract: PROTON MAGNETIC RESONANCE SPECTRA OF ANIONIC Σ-COMPLEXES OF TRINITROBENZENE WITH CYCLOPENTADIENYL AND INDENYL DERIVATIVES OF TIN

1976 ◽  
Vol 7 (50) ◽  
pp. no-no
Author(s):  
YU. A. USTYNYUK ◽  
G. A. ARTAMKINA ◽  
YU. N. LUZIKOV ◽  
YU. K. GRISHIN ◽  
A. A. AZIZOV ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Proton Magnetic Resonance ◽  
Derivatives Of ◽  
Magnetic Resonance Spectra

Cycloaddition d'ylures d'azométhine dérivés de la 3,4-dihydro-6,7-diméthoxy-3-méthoxycarbonyl-isoquinoléine

1991 ◽  
Vol 69 (7) ◽  
pp. 1156-1160 ◽  
Author(s):  
Tahar Lakhlifi ◽  
Ahmed Sedqui ◽  
Bernard Laude ◽  
Nguyen Dinh An ◽  
Joël Vebrel
Keyword(s):  
Magnetic Resonance ◽  
Key Words ◽  
Proton Magnetic Resonance ◽  
Azomethine Ylide ◽  
Magnetic Resonance Data ◽  
Resonance Data ◽  
Azabicyclic Compounds ◽  
Derivatives Of ◽  
Proton Magnetic Resonance Data

Three azomethine ylide precursors including the methyl 3,4-dihydro-6,7-dimethoxyisoquinoline-3carboxylate moiety were synthesized. The 1,3-dipolar species formed from these products react with activated dipolarophilic olefines leading diastereospecifically to derivatives of 4′,5′-dimethoxy-1,2-benzo-4,7-imino-4-methoxycarbonyl-1-cycloheptene. Proton magnetic resonance data allowed the determination of the stereochemistry of the cycloadducts. Key words: cyclic azomethine ylide, azabicyclic compounds, stereochemistry.

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