title: First stereocontrolled synthesis of (S)-cleonin and related cyclopropyl-substituted amino acids.
abstract: [reaction: see text]. Enantiomerically pure (S)-cleonin, a key component of the antitumor antibiotic cleomycin, was prepared starting from (R)-serine. The Kulinkovich cyclopropanation of the methyl ester of N-Cbz serine acetonide gave the hydroxycyclopropyl moiety. The amino alcohol region was further oxidized to amino acid. The Kulinkovich cyclopropanation allowed also the preparation of other non-natural substituted cyclopropylglycines.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Sassari, Via Vienna 2, I-07100 Sassari, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Esposito
authors.forename: P P
authors.initials: PP
authors.lastname: Piras
authors.forename: D
authors.initials: D
authors.lastname: Ramazzotti
authors.forename: M
authors.initials: M
authors.lastname: Taddei
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis*; D000903:Antibiotics, Antineoplastic / Q000138:chemical synthesis; D001761:Bleomycin / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D003521:Cyclopropanes / Q000138:chemical synthesis*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D000903:Antibiotics, Antineoplastic; D003521:Cyclopropanes; D001761:Bleomycin; C448620:cleonine; C027447:cleomycin B2