Chemical Education Today
Reports from Other Journals Gleanings from Scientific American by Paul F. Schatz Scientific American provides a rich resource of background and general interest material for topics of chemical interest that can be used to supplement and enhance chemistry lecture and laboratory courses. For this column I have selected several articles from the January to August 1996 issues of Scientific American that were particularly interesting. Taxol, a compound originally extracted from yew trees, is a promising candidate for treating various cancers, especially breast and ovarian cancer. Taxol binds to microtubules in a cell and disrupts cellular division during cell mitosis. Since cancer cells divide more frequently than healthy cells, tumor cells are killed to a greater extent than healthy cells. The dramatic effectiveness of taxol is tempered by problems such as general toxicity and difficulty in administration. Another drawback to wide use of taxol is its scarcity. Taxol is obtained by extraction of the bark of the Pacific yew, a tree found in old growth forests of the Pacific Northwest, an endangered environmental area. An article by three of the primary researchers in the taxol field gives an overview of the discovery and the mechanism of the chemotherapeutic activity of taxol derivatives. The synthesis and semisynthesis of taxol and taxol derivatives are also briefly described (K. C. Nicolaou, Rodney K. Guy, and Pierre Potier, “Taxoids: New Weapons against Cancer”, Scientific American June 1996, 274, 94–98). One of the interesting aspects of the taxol synthesis story not covered in this article was the fierce competition between a Scripps Research Institute group lead by K. C. Nicolaou and a Florida State University group lead by R. A. Holton to be the first to publish a total synthesis of taxol (K. C. Nicolaou et al., Nature 1994, 367, p. 630–634; R. A. Holton et al., JACS 1994, 116, 1994, 1597–1600). News reports of this race can be found in several other publications (S. Borman, “Total Synthesis
O
O
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of Anticancer Agent Taxol Achieved by Two Different Routes”, Chem. Eng. News, 21 Feb. 1994, 32-34; F. Flam, “Race to Synthesize Taxol Ends in a Tie”, Science 1994, 263, 911; “A Photo Finish for Total Taxol Synthesis”, Science News 1994, 145, 223). The tremendous environmental and health effects of the nuclear catastrophe in the northern Ukraine in 1986 is described by Yuri M. Shcherbak in “Ten Years of the Chornobyl Era” (Scientific American April 1996, 274, 44–49). Glenn Sorpette describes the monumental task that the Department of Energy is confronting in the cleanup and detoxification of nuclear weapons production sites in “Hanford’s Nuclear Wasteland” (Scientific American May 1996, 274, 88-97). Finally, the problem of finding a safe graveyard for high-level nuclear waste is discussed by Chris G. Whipple in “Can Nuclear Waste Be Stored Safely at Yucca Mountain?” (Scientific American June 1996, 274, 72-79). The Amateur Scientist column by Shawn Carlson often describes the construction of devices that can be useful in the chemistry laboratory. In the March issue there are instructions for the construction of a simple calorimeter that can be used for titration calorimetry (Shawn Carlson, “Exploring Chemical Bonds”, Scientific American March 1996, 274, 106–107). In the June issue there are instructions for the construction of an electrobalance capable of measuring microgram quantities (Shawn Carlson, “Homemade Microgram Electrobalances”, Scientific American June 1996, 274, 100–101). Paul F. Schatz is in the Department of Chemistry, University of Wisconsin–Madison, Madison, WI 53706;
[email protected].
OH
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HN O
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HO O
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O O
Figure 1. One appraoch to preparing taxol derivatives is modifying the side chain on the left side of the structure shown here.
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Figure 2. A ball and stick model of taxol. Carbon atoms are gray, oxygen atoms are red, nitrogen atoms are blue, and hydrogen atoms are not shown.
Journal of Chemical Education • Vol. 73 No. 10 October 1996
