1-Bromosinomenilic acid

Bromosinomeneine ketone [lxxvi]. can be made to undergo the benzil —> benzilic acid transformation in hot alkali, the product being 1-bromosinomenilic acid [xcm]. This acid is also obtained when the amorphous product of bromination of 1-bromosinomeninone with one equivalent of bromine is treated with alkali, and from sinomenine hydrate and one equivalent of bromine [69]. 

When 1-bromosinomenilic acid [xcm] is warmed above 35° C. with 20 per cent, oleum degradation to the ketone 1-bromosinomenilone [xovi] occurs. The dibromo-acid [xcrv] loses water at 150° C. in vacuo over phosphorus pentoxide to give a lactide [69]. These derivatives have also been prepared in the thebaine series [74],... 

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