ISSN:
0749-1581
Keywords:
Morphine alkaloids
;
Isocodeines
;
Conformation of ring C
;
13C and 1H NMR
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Complete 1H and 13C NMR data are reported for eleven isocodeine and seven dihydroisocodeine derivatives bearing various substituents at position 6. In isocodeines having bulky succinimido or phthalimodo groups at C-6 ring C adopts a half-boat conformation, characterized by the quasi-equatorial orientation of the C-6—N bond. The distortion from the usual boat form is due to steric interactions between C-14 and β-substituents at C-6, and it is greater in 14-hydroxy derivatives than in isocodeines unsubstituted at this position. In dihydroisocodeines the conformation of ring C is close to a chair, irrespective of the steric demand of the substituent at C-6.
Additional Material:
5 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260300617
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