A convenient approach to an advanced intermediate for (+)-lactacystin synthesis

作者：Gonda Jozef^*; Malinak David; Kovacova Margareta; Martinkova Miroslava

来源：Tetrahedron Letters, 2013, 54(49): 6768-6771.

DOI：10.1016/j.tetlet.2013.10.017

• Lactacystin
• Overman rearrangement
• alpha-Substituted alpha-amino acid
• Stereoselective synthesis

A fully stereoselective preparation of the advanced intermediate 24 for the synthesis of (+)-lactacystin from known 1,2:5,6-di-O-isopropylidene-alpha-D-gulofuranose (2), as the source of chirality, has been achieved. The C-5 methyl group was introduced via a Wittig olefination followed by Pd/C-mediated hydrogenation of the conformationally restricted alkene 11 in a highly stereoselective manner. The stereogenic tetrasubstituted carbon centre at C-3, with an amino group, was installed stereoselectively via an Overman rearrangement, which was efficiently controlled by a saccharide environment.

• 出版日期2013-12-4