The Proton Magnetic Resonance Spectrum and Structure of Himgravine

1961 ◽  
Vol 14 (1) ◽  
pp. 64 ◽  
Author(s):  
RJ Abraham ◽  
HJ Bernstein

The high resolution proton magnetic resonance spectra of himgravine and himbacine have been obtained in CHCl3 solution at 60 Mc/s. The spectra are consistent with only one of the two possible structures proposed. Other information with regard to relative orientation of groups within the molecule has also been obtained.


1969 ◽  
Vol 24 (12) ◽  
pp. 2004-2009 ◽  
Author(s):  
Erkki Rahkamaa

AbstractA sub-spectral analysis of the high resolution proton magnetic resonance spectrum of 15N-pyrrole has been performed as an AA'BB'CX spin system. Absolute values of the proton-proton and nitrogen-proton couplings have been determined. It has also been concluded that all three nitrogen-proton couplings are negative. The parameters found in the analysis of the PMR spectra of normal and deuterated pyrroles, have also been briefly reported.



1963 ◽  
Vol 41 (3) ◽  
pp. 777-782 ◽  
Author(s):  
W. M. Pasika ◽  
L. H. Cragg

The introduction of sulphate groups into dextran produces characteristic changes in its proton magnetic resonance spectrum. With linear dextran a new signal appears which can be attributed solely to an effect of sulphate groups; with branched dextran this signal coincides with that due to the branching. From a comparison of peak areas in these spectra with peak areas in the spectra of the unsulphated linear and branched dextrans it is concluded that during sulphation no appreciable degradation occurred, whether by chain scission or branch hydrolysis.The proton magnetic resonance spectra also provide evidence for preferential substitution of sulphate at carbon 2 in the anhydroglucose unit.



1969 ◽  
Vol 22 (6) ◽  
pp. 1199 ◽  
Author(s):  
GF Katekar ◽  
AG Moritz

The proton magnetic resonance spectrum at 60 MHz of pyrrole, spin- decoupled from 14N, has been studied under high resolution. Similar studies have been made on [N-D]pyrrole in which the proton spectrum was obtained simultaneously spin-decoupled from both the 14K and 2H nuclei. Analysis of the 13C-H spectra of pyrrole and [N-D]pyrrole, observed in natural abundance, gave values for all six proton-proton spin-spin couplings. Values for some of the couplings have been obtained directly and unambiguously from the spectra of samples of [S-H]pyrrole and [N- D]pyrrole in which the C-H protons have been predominantly exchanged for deuterium. The values for the couplings derived are J1,2 2.60, J1,3 2.45, J2,3 2.69, J2,4 1.44, J2,5 1.87, and J3,4 3.34 Hz.



1958 ◽  
Vol 36 (9) ◽  
pp. 1302-1307 ◽  
Author(s):  
R. J. Abraham ◽  
J. A. Pople ◽  
H. J. Bernstein

The proton magnetic resonance spectrum of methyl mercaptan has been analyzed on the basis of the nuclear grouping AB3. The spectrum calculated for [Formula: see text] agrees very well with that observed.



1973 ◽  
Vol 20 (1) ◽  
pp. K45-K48 ◽  
Author(s):  
U. Haubenreisser ◽  
B. Schnabel ◽  
G. Scheler ◽  
U. Burghoff ◽  
R. Müller ◽  
...  


1968 ◽  
Vol 46 (13) ◽  
pp. 2299-2304 ◽  
Author(s):  
P. A. J. Gorin ◽  
J. F. T. Spencer

A survey of the alkali soluble polysaccharides of yeast cells shows that galactomannans are formed by certain species of the genera Trichosporon, Schizosaccharomyces, and Nadsonia. Different species of Trichosporon form galactomannans, pentosylmannans, and a mannan. The galactomannans are distinguishable from those of Schizosaccharomyces by the H-1 region of their proton magnetic resonance spectra (recorded at 70° in D2O using an HA-100 Varian spectrometer), but the spectra of Trichosporon hellenicum and Nadsonia fulvescens galactomannans are virtually indistinguishable.The proton magnetic resonance spectrum of the Trichosporon fermentans galactomannan contains fewer signals than those of other Trichosporon galactomannans. The polymer consists predominantly of a main-chain containing a high proportion of (1 → 6)-mannopyranosyl units substituted in their 2-positions by O-α-D-galactopyranosyl-(1 → 2)-O-α-D-mannopyranosyl side-chains (1).





Sign in / Sign up

Export Citation Format

Share Document