Composition #3: Bruder, Marjorie., Haseler, Paul L., Muscarella, Marina., Lewis, William., Moody, Christopher J. Synthesis of the Oxepinochromone Natural Products Ptaeroxylin (Desoxykarenin), Ptaeroxylinol, and Eranthin . journal of organic chemistry, 2010, vol. 75, no. 2, p. 353–358. DOI: 10.1021/jo902117e.
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