Prekinamycin reductive activation

The 13C-NMR spectrum of the products arising from prekinamycin reductive activation is shown in Fig. 7.3. The identity of the compounds giving rise to the... 

SCHEME 7.22 Products arising from prekinamycin reductive activation at pH 7.5. The 13C labels are designated with asterisks ( ). 

Feldman and Eastman have suggested that the kinamycins may by reductively activated to form reactive vinyl radical (25) and orf/to-quinone methide (26) intermediates (Scheme 3.2c) [16]. The authors provided convincing evidence that the alkenyl radical 25 is generated when the model substrate dimethyl prekinamycin (24) is exposed to reducing conditions (tri-n-butyltin hydride, AIBN). Products that may arise from addition of this radical (25) to aromatic solvents (benzene, anisole, and benzonitrile) were isolated. The ort/io-quinone methide 26 was also formed,... 

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