Application of the Rodriguez-Pattenden photo-ring contraction: total synthesis and configurational reassignment of 11-gorgiacerol and 11-epigorgiacerol.

A stereospecific photochemical ring contraction was used as the key step in the first total synthesis of the marine pseudopteranyl diterpene 11-gorgiacerol and its 11-epimer. The synthesis allowed the correction of the configurations that had been misassigned in the literature. In addition, some novel pseudopteranyl derivatives have been made.