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Room-temperature (1H, 13C) and variable-temperature (1H) NMR studies on spinosin

✍ Scribed by K. C. Lewis; A. R. Maxwell; S. McLean; W. F. Reynolds; R. G. Enriquez

Publisher: John Wiley and Sons
Year: 2000
Tongue: English
Weight: 67 KB
Volume: 38
Category: Article
ISSN: 0749-1581
DOI: 10.1002/1097-458x(200009)38:9<771::aid-mrc729>3.0.co;2-4

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✦ Synopsis

Spinosin, a C-glycoside flavonoid, was isolated from the plant Desmodium tortuosum (Sw.) DC. The 1 H and 13 C NMR data acquired at room temperature exhibited doubling of signals, suggesting the presence of two rotamers in solution. Variable-temperature 1 H NMR experiments confirmed this hypothesis. T-ROESY experiments in conjunction with theoretical (MM2) calculations supported the proposal that the two rotamers interchange via rotation about the C-6-C-1 00 bond. The spectral data were completely assigned using 1 H-1 H COSY, HMQC, HSQC and HMBC experiments.

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