α-エクジソン

解説昆虫や甲殻類の脱皮，変態などに必要なホルモン．α-エクジソン：C27H44O6(464.63)(R ＝ H)．1954年にP. Karlsonらによって，カイコのさなぎから結晶状に単離され，X線回折および化学的方法でその構造が決定された．融点242 ℃．[α]D＋65°．λmax 242 nm(log ε 4.09)．カイコの前胸腺から分泌され，シダ類など多くの植物にも見いだされている．コレステロールが生合成前駆物質である．その後，昆虫，甲殻類を含む無脊椎動物から，80種類以上のエクジステロイドが見つかっている．また，植物由来のエクジステロイドはフィトエクジステロイドとよばれ，150種類以上が知られている．

説明Ecdysterone, also known as ecdysone or β-ecdysone, is a hormone that regulates the growth and development of insects. In 1954, Butenandt et al. isolated 250mg of the initial insect metamorphic active substance, ecdysone, from 500kg of silkworm pupae. Since then, various similar substances have been isolated from many plants. It has been found that ecdysteroids are not only more abundant in the plant kingdom compared to the animal kingdom, but also widely distributed and abundant in resources. Examples of ferns that contain ecdysteroids include Chinese cornbind, Sichuan cornbind, mulberry leaves, Dectenium heterocarpon, water plantain, Ginkgo biloba, yew, Thelypteris palustris, and Cyrtomium falcatum, among others.

使用α-Ecdysone is a steroidal prohormone.

純化方法Recrystallise -ecdyson from tetrahydrofuran/pet ether and from H2O as a hydrate. It has been purified by chromatogaphy on Al2O3 and elution with EtOAc/MeOH. It has max at 242nm ( 12,400). Its acetate has m 214-216o from EtOAc/pet ether, and the 2,4-dinitrophenylhydrazone has m 170-175o(dec) from EtOAc. [Karlson & Hoffmeister Justus Liebigs Ann Chem 662 1 1963, Karlson Pure Appl Chem 14 75 1967, Beilstein 8 IV 3613.]