Asymmetric induction in 8π electrocyclizations. Design of a removable chiral auxiliary.

ABSTRACT: The pseudo C(2) symmetric trans diphenyl oxazoline group acts as an effective chiral auxiliary in the 8π, 6π tandem electrocyclization of a substituted tetraene 1-carboxylic acid. Assignment of absolute stereochemistry to the [4.2.0] bicyclooctadiene product supports a model in which both s-cis and s-trans conformations favor the transition states with the same helical twist. This assignment prefaces the development of analogs of SNF4435 C and D. These natural products demonstrate activity as androgen receptor antagonists and as multidrug resistance (mdr) reversal agents.

SUBMITTER: Kim K 

PROVIDER: S-EPMC3320032 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature