title: Efficient and versatile stereoselective synthesis of cryptophycins.
abstract: The cryptophycins are a family of cyclic depsipeptides with four retrosynthetic units A to D which correspond to the respective amino acids and hydroxy acids. A new synthetic route to unit A allows the selective generation of all four stereogenic centres by introducing two of them in a catalytic asymmetric dihydroxylation, followed by substrate-controlled diastereoselective reactions. The diol also serves as the epoxide precursor. This approach provides selective access to stereoisomers of unit A (enantiomers, epimers) for structure-activity relationship studies. The unit A derivatives were incorporated into cryptophycin-1, cryptophycin-52 and a novel epimer of cryptophycin-52.
authors.affiliation: Department of Chemistry, Organic and Bioorganic Chemistry, Bielefeld University, Germany.
authors.forename: Christian Alexander
authors.initials: CA
authors.lastname: Mast
authors.forename: Stefan
authors.initials: S
authors.lastname: Eissler
authors.forename: Arvydas
authors.initials: A
authors.lastname: Stoncius
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Stammler
authors.forename: Beate
authors.initials: B
authors.lastname: Neumann
authors.forename: Norbert
authors.initials: N
authors.lastname: Sewald
mesh_terms: D001426:Bacterial Proteins / Q000138:chemical synthesis* / Q000737:chemistry; D047630:Depsipeptides / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D015394:Molecular Structure; D046937:Nostoc / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D047630:Depsipeptides