Studies with plant cell cultures of Catharanthusroseus. Oxidative coupling of dibenzylbutanolides catalyzed by plant cell culture extracts

Utilizing appropriate dibenzylbutanolides, for example 7, obtained via an efficient synthetic route from readily available aldehydes, and cell-free extracts obtained from Catharanthusroseus cell cultures, it was possible to achieve enzyme-catalyzed oxidative coupling of 7 to picropodophyllotoxin analogues. Studies are presently underway to convert such compounds to intermediates employed in the synthesis of the commercially important anti-cancer drug, etoposide.