Total synthesis of (-)-stemoamide.
A stereocontrolled total synthesis of (-)-stemoamide (1) is presented. The synthesis starts from commercially available (S)-pyroglutaminol (4). A chemoselective iodoboration of 5 was used to access key intermediate 3. The beta,gamma-unsaturated azepine derivative 2 was obtained via a Pd(0)-catalyzed sp(2)-sp(3) Negishi cross-coupling using a Reformatsky nucleophile followed by a ring-closing metathesis reaction. The required C8-C9 trans-stereochemistry of 1 was accessed through a stereoselective bromolactonization/1,4-reduction sequence.
Torssell
Staffan
S
KTH Chemical Science and Engineering, Department of Organic Chemistry, Royal Institute of Technology, S-100 44 Stockholm, Sweden.
Wanngren
Emil
E
Somfai
Peter
P
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D001381:Azepines / Q000737:chemistry; D002384:Catalysis; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D013237:Stereoisomerism
D000470:Alkaloids; D001381:Azepines; D006575:Heterocyclic Compounds, 3-Ring; D007783:Lactones; C519217:stemoamide