Optical Rotatory Dispersion Data and the Drude Equation. A Parametric Curve Fitting Problem1

1966 ◽  
Vol 70 (8) ◽  
pp. 2663-2674 ◽  
Author(s):  
Theo Burer ◽  
Leonard I. Katzin
Keyword(s):  
Curve Fitting ◽  
Optical Rotatory Dispersion ◽  
Rotatory Dispersion ◽  
Optical Rotatory ◽  
Parametric Curve ◽  
Dispersion Data ◽  
Parametric Curve Fitting

Rapeseed meal autolysis. Formation of diastereomeric (2R)-1-cyano-2-hydroxy-3,4-epithiobutanes from progoitrin

1967 ◽  
Vol 45 (17) ◽  
pp. 1971-1974 ◽  
Author(s):  
M. E. Daxenbichler ◽  
C. H. VanEtten ◽  
W. H. Tallent ◽  
I. A. Wolff
Keyword(s):  
Brassica Napus ◽  
Rapeseed Meal ◽  
Chiral Center ◽  
Optical Rotatory Dispersion ◽  
Rotatory Dispersion ◽  
Seed Meal ◽  
Optical Rotatory ◽  
Brassica Napus L ◽  
Crambe Abyssinica ◽  
Dispersion Data

When defatted seed from Brassica napus L. var. Regina II (a rapeseed) was autolyzed, its major thioglucoside (progoitrin) underwent degradation analogous to that for epiprogoitrin in Crambe abyssinica seed meal. Depending on the conditions, (R)-1-cyano-2-hydroxy-3-butene and the diastereomeric forms of (2R)-1-cyano-2-hydroxy-3,4-epithiobutane were formed in autolyzed B. napus meal instead of (S)-goitrin. The configuration at the chiral center containing the hydroxyl is assigned on the basis of known data. The configuration at carbon 3 of the episulfides is predicted on the basis of the optical rotatory dispersion data.

Flavan derivatives. XIV. The absolute configurations of some 1,2-diarylpropane derivatives and of some isoflavans

1965 ◽  
Vol 18 (7) ◽  
pp. 1035 ◽  
Author(s):  
JW Clark-Lewis ◽  
I Dainis ◽  
GC Ramsay
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Phosphorus Pentachloride ◽  
Optical Rotatory Dispersion ◽  
Rotatory Dispersion ◽  
Optical Rotatory ◽  
Aryl Group ◽  
Dispersion Data ◽  
Methylsuccinic Acid ◽  
The Absolute

The conversion of (+)-catechin tetramethyl ether into (-)-2-chloro-5,7,3',4'-tetramethoxyisoflavan is shown to proceed by 1,2-migration of the 2-aryl group with inversion of configuration at the 3-position of the flavan nucleus (the migration terminus). The chloroisoflavan was converted into (+)-cis-2-acetoxy-5,7,3',4'-tetramethoxyisoflavan and reduction of this gave (+)-2-(3,4-dimethoxyphenyl)-3-(2,4,6-trimethoxyphenyl)propan-1-ol. This was converted into the corresponding (+)-propane which gave (-)-methylsuccinic acid on ozonolysis. The (+)-propane therefore possesses the (8)-configuration corresponding to the (S)-configuration of the (+)-2,3-diarylpropan-1-ol and the (3s)-configuration of the (+)-cis-2-acetoxy-isoflavan. (+)-cis-2-Ethoxy- and (+)-cis-2-methoxy-5,7,3',4'-tetramethoxyisoflavan have been converted into the related (+)-1-alkoxy-2,3-diarylpropanes. Chlorination of the phloroglucinol nucleus in (+)-catechin tetramethyl ether may occur during reaction with phosphorus pentachloride and is shown to lead to 2,6-dichloro-5,7,3',4'-tetramethoxyisoflavan. Racemic cis- and laevorotatory and racemic trans-2-acetoxy-5,7,3',4'-tetramethoxyisoflavan have been prepared. Nuclear magnetic resonance and optical rotatory dispersion data for a number of isoflavans are reported. The absolute configurations of pterocarpin, homopterocarpin, and pisatin are inferred.

Optical rotatory dispersion studies. XLI. The absolute configuration of plicatic acid

1967 ◽  
Vol 45 (3) ◽  
pp. 319-324 ◽  
Author(s):  
R. J. Swan ◽  
W. Klyne ◽  
H. MacLean
Keyword(s):  
Carboxylic Acid ◽  
Absolute Configuration ◽  
Optical Rotatory Dispersion ◽  
Rotatory Dispersion ◽  
Optical Rotatory ◽  
Naturally Occurring ◽  
Dispersion Data ◽  
The Absolute

The absolute configuration of the naturally occurring lignan plicatic acid (I, 2,3,6-trihydroxy-7-methoxy-2-hydroxymethyl-4-(3′,4′-dihydroxy-5′-methoxyphenyl)-tetralin-3-carboxylic acid) is shown, by optical rotatory dispersion data, to be 2R,3S,4R.

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