๐”– Bobbio Scriptorium
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Slow conformational change of a thiazepinoquinoline

โœ Scribed by J.L. Huppatz; G.F. Katekar

Book ID
104248932
Publisher
Elsevier Science
Year
1970
Tongue
French
Weight
104 KB
Volume
11
Category
Article
ISSN
0040-4039

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โœฆ Synopsis

The NMR spectrum of the quinolothiazepine I (1) at 20" shows a broad hump centred about 4.26, assigned to the methylene protons adjacent to the nitrogen atom of the quinolone ring.

Above +30ยฐ

the &sorption is a triplet, which becomes fully defined at +70ยฐ. At -3O'C or lower, two principal absorptions appear at 5.26 and 3.315, with fine structure, although the latter signal is hidden under the signal due to the S-CH2-protons. These signals approximate to an AB system with J gem 12 Hz, with a chemical shift difference of about 1.96 (Fig. I).

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