Stereochemistry of olefinic bond formation in defensive steroids of Acilius sulcatus (Dytiscidae).

  title={Stereochemistry of olefinic bond formation in defensive steroids of Acilius sulcatus (Dytiscidae).},
  author={John C. Chapman and William J S Lockley and Huw H. Rees and Trevor Walworth Goodwin},
  journal={European journal of biochemistry},
  volume={81 2},
The defensive secretion of Acilius sulcatus contains a number of pregnane derivates: cortexone, 20alpha-hydroxy-4-pregnen-3-one, together with the unusual delta4,6 dienes, 6,7-dehydrocortexone, 20alpha-hydroxy-4,6-pregnadien-3-one and 4,6-pregnadien-3,20-dione. The synthesis of all these steroids except cortexone is described. Complete separation of the steroids of Acilius can be achieved by high-performance liquid chromatography on the reversed-phase column system. During biosynthesis of the… 

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