[Relationship between chemical structure and anti-arrhythmic effect of ethmosine analogs]

The relationship between the chemical structure and antiarrhthmic action in the series of 10-actlaminopropionyl phenothiazine derivatives with different urethan groups in the second position of the phenothiazine cycle (methy, ethyl and isobutyl) was studied. Subject to investigation were also aetmozine isomers containing ethyl-carbaminate in the first, third and fourth position, as well as compounds containing aminopropionyl residues in the tenth and trifluoromethyl group or bromine in the second position. The available data indicated that the antiarrhythmic action of 10-acylamino-derivatives of phenothiazine depends not only on the structure of the side chain and substitution of hydrogen in the second position of the phenothiazine nucleus, but also upon the position of the urethan group in the phenothiazine cycle. Moving ethyl-carbaminate to the first, third and fourth positions results in the fall of the anti-arrhythmic action. The absence of any relation between the length of the urethan radical and the effect produced by the substance was also shown. By substituting the methyl or isobutyl radicals for the ethyl one the antiarrthythmic action of the substances declines.