title: Copper-mediated dimerization to access 3a,3a'-bispyrrolidinoindoline: diastereoselective synthesis of (+)-WIN 64821 and (-)-ditryptophenaline.
abstract: A copper-mediated cyclization and dimerization of tryptamine or tryptophan was developed to generate a C2-symmetry C3(sp(3))-C3(sp(3)) bridge with two contiguous stereogenic quaternary carbons in one step. Impressively, the ratio between exo and endo cyclization products varies when different protecting groups of Nb are utilized. This dimerization reaction could be conducted in gram scale. With this dimerization method, both endocyclotryptophan (+)-WIN 64821 and exocyclotryptophan (-)-ditryptophenaline were synthesized in 5 steps.
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, Yunnan, China.
authors.forename: Kangjiang
authors.initials: K
authors.lastname: Liang
authors.forename: Xu
authors.initials: X
authors.lastname: Deng
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Tong
authors.forename: Dashan
authors.initials: D
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Ding
authors.forename: Ankun
authors.initials: A
authors.lastname: Zhou
authors.forename: Chengfeng
authors.initials: C
authors.lastname: Xia
mesh_terms: D003300:Copper / Q000737:chemistry*; D003500:Cyclization; D019281:Dimerization; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D010879:Piperazines / Q000138:chemical synthesis* / Q000737:chemistry; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D014363:Tryptamines / Q000737:chemistry*; D014364:Tryptophan / Q000737:chemistry*
chemical_list: C000600601:3a,3a'-bispyrrolidinoindoline; D007211:Indoles; D010879:Piperazines; D011758:Pyrroles; D014363:Tryptamines; C437184:ditryptophenaline; C087461:WIN 64821; C030820:tryptamine; D003300:Copper; D014364:Tryptophan