Concise formal synthesis of porothramycins A and B via Zincke pyridinium ring-opening/ring-closing cascade.
Short formal syntheses of the antitumor antibiotics porothramycins A and B from a commercially available ester of the unnatural amino acid 3-(3-pyridyl)alanine are presented. A rearrangement cascade that presumably involves a Zincke-type pyridinium ring-opening followed by cyclization of a pendant nucleophilic amide generates the salient pyrroline ring of the alkaloids.
Michels
Theo D
TD
Department of Chemistry, The University of California, Irvine, California 92697-2025, USA.
Kier
Matthew J
MJ
Kearney
Aaron M
AM
Vanderwal
Christopher D
CD
D000876:Anthramycin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D003500:Cyclization; D008968:Molecular Conformation; D011726:Pyridinium Compounds / Q000737:chemistry*; D013237:Stereoisomerism
D011726:Pyridinium Compounds; D000876:Anthramycin; C057883:porothramycin B; C057882:porothramycin A