To explore and screen the candidates of the selective muscle-relaxant antagonist against amino-steroid nondepolarizing muscle relaxants.Two 6-deoxy-6-thioether-acetylglycine-γ-cyclodextrin derivatives, Aom0498-1 and Aom0498-3 were synthesized using one-pot reaction.(1) γ-Cyclodextrin, Aom0498-1, Aom0498-3 and sugammadex 1.8, 3.6 and 5.4μmol·L-1 were added to phrenic-nerve-diaphragm preparation of mice accordingly and the reversal rate of muscle contraction was recorded.(2) Guinea pigs were iv administered with γ-cyclodextrin, Aom0498-1, Aom0498-3 and sugammadex 2 mg·kg-1 accordingly and recovery time of train-of-four ratio to 50% and 75% was recorded.(3) Rabbits were iv administered with γ-cyclodextrin, Aom0498-1, Aom0498-3 and sugammadex 6 mg·kg-1 accordingly after paralysis and recovery time of the ear pinch reflex was recorded.(4) Aom0498-1 and Aom0498-3 2, 4 and 8 g·kg-1 were iv given once time accordingly and clin. signs were monitored.(1) In mouse phrenic-nerve-diaphragm preparation model, the reversal rates of muscle contraction in Aom0498-1 1.8, 3.6 and 5.4μmol·L-1 groups[(2.5±1.0)%, (6.9±2.6)% and(24.5±9.1)%] and those in Aom0498-3 groups[(17.4±1.7)%, (65.5±0.6)% and(100±8.9)%]were significantly higher than those in the corresponding groups of γ-cyclodextrin[(1.1±0.5)%, (2.6±0.7)%, and(10.3±6.1)%](P<0.05).The reversal rates of muscle contraction in Aom0498-3 1.8, 3.6 and 5.4μmol·L-1 groups were significantly higher than those in sugammadex groups.The reversal rates of muscle contraction in Aom0498-1 1.8, 3.6 and 5.4μmol·L-1 groups were significantly lower than those in sugammadex groups.(2) In the guinea pig model, the time for recovery of the train-of-four ratio to 50% and 75% in Aom0498-3 2 mg·kg-1 group was significantly shorter than that in γ-cyclodextrin 2 mg·kg-1 group(P<0.05), and was equivalent to that in sugammadex 2 mg·kg-1 group.The recovery time of the train-of-four ratio to 50% in Aom0498-1 2 mg·kg-1 group was significantly shorter than that in γ-cyclodextrin 2 mg·kg-1 group, and the recovery time of the train-of-four ratio to 75% in Aom0498-1 2 mg·kg-1 group was significantly longer than that in sugammadex 2 mg·kg-1 group.(3)In the rabbit model, the recovery time in Aom0498-1 6 mg·kg-1 group and in Aom0498-3 6 mg·kg-1 group was significantly shorter than that in γ-cyclodextrin 6 mg·kg-1 group(P<0.05).And the recovery time in Aom0498-3 6 mg·kg-1 group was significantly shorter than that in sugammadex 6 mg·kg-1 group.Single dose toxicity test showed that more mice in sugammadex 2, 4 and 8 g·kg-1 groups with transient to mild side effects were observed when compared with those in the corresponding dose groups of Aom0498-1 or Aom0498-3.Aom0498-1 and Ao0498-3 are of high reversal activities against sugammadex, indicating that the series of γ-cyclodextrin derivatives might be served as potential candidates of selective muscle-relaxant antagonists.