Ecdysone metabolism and biological activity

The 26-hydroxyl group is further oxidized to ecdysonoic acid (119) and 20-hy-droxyecdysonoic acid (120) [205] which have been identified in developing eggs of the desert locust, S. gregaria (Fig. 23). The occurrence of both compounds in Spodoptera littoralis pupae was also established. These oxidations are apparently inactivation steps. 26-Hydroxylation, 3-epimerization, 3-acetylation, and conjugation diminish the interaction with the steroid receptor and thus cem be viewed as inactivation. 

The author wishes to thank Prof. C.J.W. Brooks, University of Glasgow, and Prof. E. Ohnishi, Nagoya University, for their review of this manuseript. 

5 Carlson, R.M.K., Tarchini, C. and Djerassi, C. (1980) in Frontiers of Bio-Organic Chemistry and Molecular Biology (Ananchenko, S.N., Ed.) pp. 211-224, Pergamon Press, Oxford. 

6 Minale, L. and Sodano, G. (1977) in Marine Natural Products Chemistry (Faulkner, D.J. and Fenical, W.H., Eds.) pp. 87-109, Plenum Press, New York. 

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