Radical-mediated opening of a trisubstituted epoxy alcohol using cp(2)TiCl was followed by diastereoselective reduction of the resulting product with a centrally located methylene group, flanked on both sides by two chiral hydroxyl-bearing carbons, to build all the three chiral centers of (+)-prelactone B 1 in their desired stereochemistries leading to the total synthesis of the molecule. (C) 2003 Elsevier Science Ltd. All rights reserved.
The methyl ester of ()-ceriferic acid-I, a 14-membered ring sesterterpene isolated from the wax of the scale insect , was synthesized by means of an intramolecular Wittig-type reaction.
Synthesis of the C17–C25 subunit of lasonolide A utilizing a Tsuchihashi–Yamamoto type rearrangement
作者:Kailas B. Sawant、Fei Ding、Michael P. Jennings
DOI:10.1016/j.tetlet.2007.05.160
日期:2007.7
An efficient synthesis of the C17–C25 subunit resident in (−)-lasonolide A is reported herein. The key reaction features that were utilized include a Tsuchihashi–Yamamoto type rearrangement and Molander–Reformatsky SmI2 mediated intramolecular aldol reaction sequence. Lastly, a diastereoselective target oriented β-C-glycoside formation sequence via an oxocarbenium reduction completed the stereochemistry