[en] Information has been obtained concerning the dependence of the antiradiation effect on chemical structure, particularly on the substitute in the β position of the alkyl chain of tryptamine. The example of the indole analog of adrenalin was used to confirm the previously observed fact that introducing a hydroxyl group in this position enhances the radioprotective effect of a compound

[en] In experiments on mice a study was made of different substutuents in the 4th position of the indole ring of 5-methoxytryptamines (5-MOT) on toxicity and radioprotective efficiency of the compounds of this class. It was shown that the administration of the amino-group to a mexamine molecule increased the preparation toxicity; the nitro-group somewhat diminished the toxic properties, and the acetylaminogroup did not change 5-MOT toxicity. A 5-MOT derivative with a notro-group possessed the strongest radioprotective action. The radioprotective efficiency of these compounds persisted for 1-2 h