Muller matrix approach for determination of optical rotation in chiral turbid media in backscattering geometry

2006 ◽  
Author(s):  
S. Manhas ◽  
M. K. Swami ◽  
P. Buddhiwant ◽  
N. Ghosh ◽  
P. K. Gupta ◽  
...  
Keyword(s):  
Optical Rotation ◽  
Turbid Media ◽  
Matrix Approach

scholarly journals Mueller matrix approach for determination of optical rotation in chiral turbid media in backscattering geometry

2006 ◽  
Vol 14 (1) ◽  
pp. 190 ◽  
Author(s):  
S. Manhas ◽  
M. K. Swami ◽  
P. Buddhiwant ◽  
N. Ghosh ◽  
P. K. Gupta ◽  
...  
Keyword(s):  
Optical Rotation ◽  
Mueller Matrix ◽  
Turbid Media ◽  
Matrix Approach

Mueller matrix decomposition for determination of optical rotation of glucose molecules in turbid media

2014 ◽  
Vol 19 (4) ◽  
pp. 046015 ◽  
Author(s):  
Ping Sun ◽  
Yongchao Ma ◽  
Wei Liu ◽  
Qinghua Yang ◽  
Qiongzhen Jia
Keyword(s):  
Optical Rotation ◽  
Matrix Decomposition ◽  
Mueller Matrix ◽  
Turbid Media

scholarly journals A glucan from active dry baker’s yeast (Saccharomyces cerevisiae): A chemical and enzymatic investigation of the structure

2003 ◽  
Vol 68 (11) ◽  
pp. 805-809 ◽  
Author(s):  
Dragan Zlatkovic ◽  
Dragica Jakovljevic ◽  
Djordje Zekovic ◽  
Miroslav Vrvic
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Optical Rotation ◽  
Linear Chain ◽  
Periodate Oxidation ◽  
Methylation Analysis ◽  
Yeast Saccharomyces Cerevisiae ◽  
New Approach ◽  
Main Structural Feature ◽  
Or Groups

The structure of a polysaccharide consisting of D-glucose isolated from the cell-wall of active dry baker?s yeast (Saccharomyces cerevisiae) was investigated by using methylation analysis, periodate oxidation, mass spectrometry, NMR spectroscopy, and enzymic hydrolysis, as a new approach in determination of structures. The main structural feature of the polysaccharide deduced on the basis of the obtained results is a linear chain of (1?3)-linked ?-D-glucopyranoses, a part of which is substituted through the positions O-6. The side units or groups are either a single D-glucopyranose or (1?3)-?-oligoglucosides, linked to the main chaing through (1?6)-glucosidic linkages. The low optical rotation as well as the 13C-NMR and FTIR spectra suggest that the glycosidic linkages are in the ?-D-configuration.

scholarly journals Chiral Resolution and Absolute Configuration of 3α,6β-Dicinnamoyloxytropane and 3α,6β-Di(1-ethyl-1H-pyrrol-2-ylcarbonyloxy)tropane, Constituents of Erythroxylum Species

2014 ◽  
Vol 9 (1) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Marcelo A. Muñoz ◽  
Solange Arriagada ◽  
Pedro Joseph-Nathan
Keyword(s):  
Stationary Phase ◽  
Natural Product ◽  
Absolute Configuration ◽  
Optical Rotation ◽  
Normal Phase ◽  
Vibrational Circular Dichroism ◽  
Chiral Resolution ◽  
Case Characteristic ◽  
The Absolute

Chiral resolution of (±)-3α,6β-dicinnamoyloxytropane (1) and (±)-3α,6β-di(1-methyl-1 H-pyrrol-2-ylcarbonyloxy)tropane (2), prepared by esterification of (±)-3α,6β-tropanediol (3), was achieved using an amylose-derived HPLC stationary phase and normal phase conditions. The corresponding vibrational circular dichroism (VCD) spectra provided the absolute configuration of the enantiomers as (-)-(3 R,6 R)-1, (+)-(3S,6S)- 1, (-)-(3 R,6 R)-2 and (+)-(3S,6S)- 2. In each case, characteristic VCD bands for the absolute configuration determination of the 3α,6β-tropandiol esters were observed. While the absolute configuration of natural 1, previously isolated from Erythroxylum hypericifolium, could not be established due to the lack of literature optical rotation values, that of catuabine E, previously isolated from E. vacciniifolium, is now assigned as (-)-(3 R,6 R)-2 by comparison with the optical rotation values of the prepared samples and the reported rotation of the natural product.

scholarly journals Isolation, determination of structure and synthesis of the acid-labile conjugate of aldosterone

1976 ◽  
Vol 157 (1) ◽  
pp. 1-14 ◽  
Author(s):  
P C Carpenter ◽  
V R Mattox
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Methyl Ester ◽  
Resonance Spectrum ◽  
Optical Rotation ◽  
The Other ◽  
Acetate Methyl ◽  
Human Volunteers ◽  
Homogeneous Acid ◽  
Acid Labile

1. After administration of 600mg of 3H-labelled aldosterone to human volunteers, 57 mg of homogeneous acid-labile conjugate was isolated from the urine and identified as aldosterone 18 beta-D-glucosiduronic acid. 2. Esterification and acetylation of the conjugate gave a tetra-acetate methyl ester, which, by measurement of the optical rotation and nuclear-magnetic-resonance spectrum, was shown to be a beta-glucosiduronate. This tetra-acetate methyl ester was synthesized in approx. 10% yield by the Koenigs-Knorr procedure. 3. Removal of the acetyl and methyl ester groups from the tetra-acetate methyl ester with alkali was accompanied by almost complete isomerization at C-17 to give 17-isoaldosterone 18 beta-D-glucosiduronic acid. 4. To prevent inversion at C-17 during removal of the acetate and ester groups of beta-glucosiduronate (a) the 3,20-disemicarbazone was prepared, (b) the acetate and ester groups were removed from the disemicarbazone by treatment with alkali, and (c) the semicarbazone groups were removed from the product at pH 2.0, and aldosterone 18 beta-D-glucosiduronic acid was obtained in 47% overall yield. 5. In the presence of components used to synthesize beta-glucosiduronate by the Koenigs-Knorr reaction this substance is converted slowly into the alpha-glucosiduronate; this conversion is responsible, in part, for the low yield of beta-glucosiduronate. 6. Two additional conjugates were obtained in the Koenigs-Knorr reaction; a provisional structure was assigned to one substrate. The other substance is a C-18 alpha-glucosiduronate. Removal of the acetyl and ester groups from C-18 alpha-glucosiduronate gave the alpha-glucosiduronic acid in 84% yield and the 17-isoaldosterone alpha-glucosiduronic acid in 12% yield. 7. The rate at which several types of beta-glucuronidase hydrolyse the foregoing steroidal alpha- and beta-glucosiduronic acids is given.

scholarly journals Laser optoacoustic imaging of turbid media: determination of optical properties by comparison with diffusion theory and Monte Carlo simulation

1996 ◽  
Author(s):  
Alexander A. Oraevsky ◽  
Rinat O. Esenaliev ◽  
Frank K. Tittel ◽  
Martin R. Ostermeyer ◽  
Lihong V. Wang ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Optical Properties ◽  
Diffusion Theory ◽  
Turbid Media ◽  
Optoacoustic Imaging
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