Chemistry Reference
In-Depth Information
Scheme 4.10 Examples of disfavored reactions catalyzed by antibo-
dies. (A) Antibody 22C8 was generated against the bicyclo[2.2.2]octene
derivative 20 and catalyzes the exo cycloaddition of diene 21 to acry-
lamide 22. (B) The energetically demanding syn elimination of 24 is
accelerated by antibody 1D4. The latter was produced by the confor-
mationally restricted hapten 23, which contains an ammonium group
to induce a catalytic base. (C) Antibody 26D9, elicited with amine oxide
25, reverses the normal preference for formation of five-membered
rings in the reaction of 26 to give enantiomerically pure tetrahydropyran
via the higher energy 6-endo transition state.
Scheme 4.11 Activation of a prodrug of the anticancer agent eto-
poside via tandem retro-aldol/retro-Michael reactions catalyzed by
antibody 38C2.
