Some reactions of ajmaline about N-4 partial formulae

Some reactions of ajmaline about N-4 (partial formulae) 

In an unusual reaction ajmaline refluxed with Raney-nickel in xylene decarbonylates and this observation has been of use in the isolation of the C-21 atom in biosynthetic work. 

That the 17-hydroxyl group was secondary and in a five membered ring was shown by its Oppenauer oxidation to a ketone (infrared spectrum indicative of a cyclopentanone). Reduction of this ketone would have been expected to proceed by addition of the hydrogen on the unhindered face that is the one before the 

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