PHARMACOLOGICAL PROPERTIES OF SYMPATHOMIMETIC DIAMINES

¹ Scientific Department, Hoffmann-La Roche, Inc., Nutley, New Jersey

A series of 25 aromatic and aliphatic alkylene-,-diamines have been studied.

Most of the arylalkylenediamines may be considered as derived either from alkanolamines by substituting an amino group for the alcoholic hydroxyl group or from alkylmono-amines by introducing a second amino group.

The diamines are usually less toxic but also less potent pressor substances than the corresponding alkanolamines but are in many instances as potent as the corresponding alkylmono-amines.

Of the 5 major variations in position of the amino groups in the alkyl chain—phenylethylenediamine, phenyl-1,2-propanediamine, phenyl-2,3-propanediamine, phenyl-2,3-butanediamine and 2,3-alkyldiamine only compounds of the first type such as 1-(3,4-dihydroxy phenyl)-N2-methylethylenediamine (Nu-1408), 1-(m-hydroxyphenyl)-N²-methylethylenediamine (Nu-1683), its di-isomer (Nu-2013) and the corresponding primary diamines, Nu-1825 and Nu-1896, possess sufficiently high pressor activity to be of interest. Nu-1683 and Nu-2013 resemble ephedrine in pressor potency and duration of action, but are one-third as toxic, lack the central stimulating action and do not produce tachyphylaxis.

The phenylethylenediamines are oxidized by amine oxidase at the same rate as the corresponding mono-amines.