Anti podophyllotoxin lignans

Another anti-cancer agent in clinical use is podophyllotoxin (3-59) this has an aryl tetrahydronaphthalene lignan lactone skeleton, and demonstrates potent tubulin-binding, anti-mitotic properties (Scheme 3.16) [30]. The Sherburn group [31] prepared this molecule by a tris(trimethylsilyl)silane promoted conversion of thionocarbonate 3-55 into the lactone 3-58, which proceeded with a yield of 38 %. As intermediates, the radicals 3-56 and 3-57 can be assumed. 

Podophyllotoxin (Fig. 4), a non-alkaloid toxin lignan, is a laxative, anti-tumor and antirheumatic agent. Cell cultures of Linum flavum were shown to be able to convert deoxypodophyllotoxin, a lignan isolated from Anthriscus sylvestris, into podophyllotoxin. ... 

MacRae and Towers (106) reviewed the biological activities of the lignans and discussed those that are toxic to fungi, insects, and vertebrates, as well as those lignans that are known to have anti-tumor, anti-mitotic, and anti-viral activities. The most studied lignan thus far is podophyllotoxin because of its anti-cancer activity. However, podophyllotoxin is itself toxic (144). 

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