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Azobilirubin isomers: NMR structure determination using a shift reagent

✍ Scribed by Manuel Salmón; E. Díaz; M. C. Rock; Catherine Fenselau

Publisher
John Wiley and Sons
Year
1976
Tongue
English
Weight
283 KB
Volume
8
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The isomeric benzeneazodipyrromethene derivatives, obtained from the reaction of bilirubin and a phenyldiazonium salt were separated as their corresponding methyl esters. The lanthanide‐induced chemical shifts, coupling constants and double irradiation experiments permit direct assignment of methyl and vinyl substituent positions in these bilirubin‐derived isomers.

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