Syntheses et activites biologiques de certains derives thyroxiniens et adrenergiques—III

Some biological effects, both systemic and at the level of adrenals and thyroid, of iodosynephrines and iodothyroadrenalines are studied. lodosynephrines, like synephrine itself but contrary to adrenaline, have no action on L-ascorbic acid and cholesterol level in the adrenals. They do not significantly alter the basal metabolism of normal or thyroidectomized rats. The hyperglycemic activity of diiodo-3:5 synephrine is much less than that of adrenaline, a fact which may explain why iodosynephrines have no action at all on the cardiac rythm or respiratory exchanges. lodothyroadrenalines, having no marked adrenergic activity, show a number of thyromimetic properties: they depress the 131 I thyroidal uptake, counteract to a certain extent the experimental goitre induced by synthetic anti-thyroid agents and display a metamorphogenic activity. They have however no detectable effect on respiratory exchanges or cardiac rythm. Some conclusions are drawn with respect to the relations between activity and structure within the series of sympathomimetic and thyromimetic agents.