Stereocontrolled Synthesis of Marine Cytotoxic Natural Product.

Natural Product Synthesis AConcise Asymmetric Synthesis of the Marine Hepatotoxin 7-Epicylindrospermopsin**

The cyanobacterial toxin cylindrospermopsin (1) was isolated as the principal hepatotoxin from Cylindrospermopsis raciborskii in 1992 after suspicion of its involvement in an outbreak of hepatoenteritis that hospitalized 150 people on Palm Island, Australia. It has since been isolated in Japan from Umezakia natans and in Israel from Aphazinomenon ovalisporum. Following the discovery of the pare...

Natural Product Synthesis

The Lycopodium alkaloids are a family of structurally complex natural products, which have provoked long-term interests in their total syntheses because of their unique and fascinating architectures and potential biological activities. In particular, fawcettimine-type Lycopodium alkaloids, such as fawcettimine (1) and fawcettidine (2) (Scheme 1), have attracted broad attention from the syntheti...

Natural Product Chemistry of the Marine Sponges

A systematic search for constituents of marine sponges has yielded over one hundred new compounds, most of them with unique structural features. A broad survey of the field is presented and certain topics, particularly those closely related to recent work done in our own laboratory on sesquiterpenoids, are discussed in more detail.

Stereocontrolled total synthesis of (+)-UCS1025A.

Stereocontrolled total synthesis of (+)-vincristine.

An efficient total synthesis of (+)-vincristine has been accomplished through a stereoselective coupling of demethylvindoline and the eleven-membered carbomethoxyverbanamine presursor. Demethylvindoline was prepared by oxidation of 17-hydroxy-11-methoxytabersonine, followed by regioselective acetylation with mixed anhydride method. Although an initial attempt of coupling by using demethylvindol...