Anticancer Agents from the Australian Tropical Rainforest: Spiroacetals EBC-23, 24, 25, 72, 73, 75 and 76
作者:Lin Dong、Heiko Schill、Rebecca L. Grange、Achim Porzelle、Jenny P. Johns、Peter G. Parsons、Victoria A. Gordon、Paul W. Reddell、Craig M. Williams
DOI:10.1002/chem.200901525
日期:2009.10.26
EBC‐23, 24, 25, 72, 73, 75 and 76 were isolated from the fruit of Cinnamomum laubatii (family Lauraceae) in the Australiantropicalrainforests. EBC‐23 (1) was synthesized stereoselectively, in nine linear steps in 8 % overall yield, to confirm the reported relative stereochemistry and determine the absolute stereochemistry. Key to the total synthesis was a series of Tietze–Smith linchpin reactions
Microwave-Assisted Synthesis of Substituted Tetrahydropyrans Catalyzed by ZrCl<sub>4</sub> and Its Application in the Asymmetric Synthesis of <i>exo</i>- and <i>endo</i>-brevicomin
作者:Surendra Singh、Patrick J. Guiry
DOI:10.1021/jo901019u
日期:2009.8.7
ZrCl4-catalyzed deprotection of 1,3-dioxane/dioxalane and the simultaneous formation of 6-methoxy-substituted tetrahydropyrans proceeded under microwave irradiation in good yield. This synthetic methodology was used for the asymmetric synthesis of (+)-exo- and (+)-endo-brevicomin in 55% overall yield over 4 steps.