ORGN 724 |
| The cucurbitacins, 1, are representatives of highly oxygenated, tetracyclic triterpene plant substances, predominantly from the Cucurbitaceae family. These triterpenoids have received considerably attention due to their medicinal properties as anti-cancer compounds, and also, for their toxicity. Our approach to the cucurbitacins features two novel strategies, one of which will lead to their total synthesis and the other, in which several synthetic transformations on (+)-estrone, 2, will lead to a cucurbitane-like structure. The Wieland-Miescher ketone, 3, was found to be a suitable starting material for the de novo synthesis of cucurbitacins, which was reduced, leading to the formation of the CD synthon. Following a Grignard reaction with 3-methoxybenzyl chloride, acidification, dehydration, and oxidation led to the formation of 4. Synthetic transformations on (+)-estrone led to the formation of a hexanor-cucurbitane-like structure, 5, which served as a starting point for investigations leading to the addition of the side-chain with trimethylsilyl cyanide and under the Heck Reaction conditions. Both synthetic strategies will be presented.
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Total Synthesis, Materials, Molecular Recognition, Process R&D, and Physical Organic Chemistry
8:00 PM-10:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster
Division of Organic Chemistry |
