title: Gram-scale synthesis of (+)-spongistatin 1: development of an improved, scalable synthesis of the F-ring subunit, fragment union, and final elaboration.
abstract: In a quest to develop an effective, scalable synthesis of (+)-spongistatin 1 ( 1), we devised a concise, third-generation scalable synthesis of (+)- 7, the requisite F-ring tetrahydropyran aldehyde, employing a proline-catalyzed cross-aldol reaction. Subsequent elaboration to (+)-EF Wittig salt (+)- 3, followed by union with advanced ABCD aldehyde (-)- 4, macrolactonization and global deprotection permitted access to >1.0 g of totally synthetic (+)-spongistatin 1 ( 1).
authors.affiliation: Department of Chemistry, Monell Chemical Senses Center, and Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Amos B
authors.initials: AB
authors.lastname: Smith
authors.forename: Takashi
authors.initials: T
authors.lastname: Tomioka
authors.forename: Christina A
authors.initials: CA
authors.lastname: Risatti
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Sperry
authors.forename: Chris
authors.initials: C
authors.lastname: Sfouggatakis