Total synthesis of the antitumor antibiotic (+/-)-fredericamycin A by a linear approach.
A linear approach to the total synthesis of racemic fredericamycin A (1) through the oxidative intramolecular [4 + 2] cycloaddition of a (phenylthio)acetylene-cobalt complex is described, which is applicable for the asymmetric total synthesis of naturally occuring 1. The highlight of this work is the aromatic Pummerer-type reaction with 1-ethoxyvinyl chloroacetate, which effects the introduction of the oxygen functional group to the internal B-ring of the highly functionalized, congested polyaromatic ABC-ring moiety.
Kita
Y
Y
Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan. kita@phs.osaka-u.ac.jp
Iio
K
K
Kawaguchi
K
K
Fukuda
N
N
Takeda
Y
Y
Ueno
H
H
Okunaka
R
R
Higuchi
K
K
Tsujino
T
T
Fujioka
H
H
Akai
S
S
D000903:Antibiotics, Antineoplastic / Q000138:chemical synthesis*; D003500:Cyclization; D007546:Isoquinolines / Q000138:chemical synthesis*; D010084:Oxidation-Reduction; D013141:Spiro Compounds / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000903:Antibiotics, Antineoplastic; D007546:Isoquinolines; D013141:Spiro Compounds; C016660:fredericamycin A