Abstract: Thirty-five amino-lipoates were synthesized and their antiradiation activity investigated. The polymerizable dithiolane ring possibly represents the main effective part, while the side chain the less effective part, as it may be altered to certain extent without losing antiradiation activity.Four different routes were described for synthesizing these amino-lipoates with satisfactory results. Improved methods for synthesizing the intermediates were also reported.Compounds no. 2, 4, 22, 24, 25, 27, 29, 30, 31, 34 and 35 when administered intraperitoneally before irradiation increased the survival of mice to 50～70%. Compounds no. 24 and 27 were found to be effective when administered orally before irradiation, increasing 40% of the survival. Compounds no. 19, 25, 27 and 30 when administered intraperitoneally after irradiation, increased 25～45% of the survival. All these data are statistically significant in comparison with the control. Compound no.10 increased the leucocyte count in the peripheral blood in dogs.