Pharmacological studies of a group of semi-synthetic structural analogues of glaucine

Glaucine and the newly-synthesized compounds possess some general properties conditioned by the common apomorphine structure - inhibition of the central nervous system, brief decrease in blood pressure and spasmolytic action. At the same time the changes in the structure of glaucine lead to quantitative or qualitative changes in some of its effects. Substitution of hydrogen in 3rd position with -CH2. NH-group reduces glaucine toxicity 3.5 times. Still greater decrease in the toxicity (7.5-10 times) is found in the case of N-oxidation or dehydrogenation of glaucine. The extension of the methyl group in 3rd position with a hydroxy group or with an amide residue of the benzoic acid, as well as the dehydrogenation and N-oxidation of glaucine, lead to intensification of the inhibitory action on the central nervous system. With the exception of 7-methyl dehydroglaucine which has antitussive action similar to glaucine, the other glaucine structural analogues do not possess this property. Both glaucine and its structural analogues exercise a bronchoconstrictor effect. 3-Aminomethyl derivatives preserve the spasmolytic activity of glaucine, and their several-fold lower toxicity makes them more promising spasmolytic agents than glaucine. Dehydrogenation and N-oxidation of glaucine reduce considerably its spasmolytic action.