Anthranilic acid derivatives

A method of treating diabetes by lowering the glucose levels in blood plasma comprising administering to a diabetic host a therapeutically effective amount of a compound of formula I:

• ##STR16## wherein R.sub.o is bromo, chloro, fluoro, nitro or trifluoromethyl,
• R is hydrogen, C.sub.1-6 alkyl or C.sub.2-18 alkanoyl, and
• R.sub.1 is hydrogen or C.sub.1-12 alkyl,
• or a pharmaceutically acceptable simple or acid addition salt thereof, said therapeutically effective amount being an amount effective for the treatment of diabetes.