ABSTRACT

Figure 1. Structures of (I) ecdysone,(%) 20-hydroxyecdysone, (5) ~ehydroecdysone, (4) 25-deoxyecdysone, (S) ponasterone A. and (6) 2,22,25-trideoxyecdyaone.

166 CHANG

Some work has been conducted on the metabolism of ecdysteroids. Ecdysone is rapidly hydroxylated to 20-hydroxyecdysone by a variety of tissues in several species (Lachaise and Feyereisen, 1976; Lachaise et al., 1976; Chang and O'Connor, 1978). 25-Deoxyecdysone is converted to ponasterone A (25-deoxy-20-hydroxyecdysone; Fig. 1) by various tissues in C. mamas (Lachaise et al., 1986). 3-Dehydroecdysone is converted to 20-hydroxyecdysone by various tissues in 0. limosus (Backing et al., 1995).