Bollenbacher W E, Galbraith M N, Gilbert L I, Horn D H
Steroids. 1977 Jan;29(1):47-63. doi: 10.1016/0039-128x(77)90108-8.
alpha-Ecdysone (2beta,3beta,14alpha,22R,25-pentahydroxy-5beta-cholest-7-en-6-one) has been identified as the metabolism product of 3beta,14alpha-dihydroxy-5beta-cholest-7-en-6-one in isolated prothoracic glands of the tobacco hornworm, Manduca sexta. In contrast, 3beta-hydroxy-5beta-cholest-7-en-6-one is metabolized to 14-deoxy-alpha-ecdysone and a variety of intermediates all lacking the 14-hydroxy group. The results suggest that either the normal precursor for the synthesis of alpha-ecdysone by prothoracic glands is a sterol more highly oxygenated than cholesterol or that hydroxylation of a minimally oxygenated precursor at C-14 must precede introduction of the C-6 ketone and/or delta7 bond. The data further suggest that several alternative hydroxylation routes may exist for the latter steps of alpha-ecdysone biosynthesis.
α-蜕皮激素（2β,3β,14α,22R,25-五羟基-5β-胆甾-7-烯-6-酮）已被确定为烟草天蛾（Manduca sexta）离体前胸腺中3β,14α-二羟基-5β-胆甾-7-烯-6-酮的代谢产物。相比之下，3β-羟基-5β-胆甾-7-烯-6-酮被代谢为14-脱氧-α-蜕皮激素和各种均缺乏14-羟基的中间体。结果表明，前胸腺合成α-蜕皮激素的正常前体要么是一种比胆固醇氧化程度更高的甾醇，要么是在引入C-6酮基和/或δ7键之前，必须先将最低氧化程度的前体在C-14位进行羟基化。数据还进一步表明，α-蜕皮激素生物合成的后期步骤可能存在几种替代的羟基化途径。
