Progress in the Chemistry of Cytochalasans
99
the key to success in the syntheses of cytochalasans is to construct these tricyclic
ring systems, which can be disconnected in various ways and lead to two types of
synthetic design. Thus, on the one hand, the isoindolone core and the macrocyclic
fused ring may be constructed simultaneously through a late-stage intramolecular
Diels–Alder condensation, as represented by the total synthesis of cytochalasin B
HN
O
O
OH
HN
O
OH
HO
HN
O
OH
HO
408 (periconiasin D)
409 (periconiasin E)
410 (periconiasin F)
398 (aspergillin PZ)
NH
O O
O
OH
A–tricyclic scaffolds of cytochalasans
B–polycyclic architectures
110 (cytochalasin B)
HN
O
HO
OH
O
O
HN
O OAc
OH
26 (L-696,474)
412 (periconiasin G)
HN
O O
HN
O O
HO
404 (periconiasin A)
202 (phenochalasin A)
O
O
HN
O
O
OH
O
HO
C–merocytochalasans
NH
O O
O
OH
O
OH
O
HO
448 (asperchalasine B)
NH
O O
O
OH
O
O
HO
OH
NH
O O
O
OH
O
O
HO
OH
450 (asperchalasine D)
449 (asperchalasine C)
Fig. 22 Typical structures of cytochalasans
99
the key to success in the syntheses of cytochalasans is to construct these tricyclic
ring systems, which can be disconnected in various ways and lead to two types of
synthetic design. Thus, on the one hand, the isoindolone core and the macrocyclic
fused ring may be constructed simultaneously through a late-stage intramolecular
Diels–Alder condensation, as represented by the total synthesis of cytochalasin B
HN
O
O
OH
HN
O
OH
HO
HN
O
OH
HO
408 (periconiasin D)
409 (periconiasin E)
410 (periconiasin F)
398 (aspergillin PZ)
NH
O O
O
OH
A–tricyclic scaffolds of cytochalasans
B–polycyclic architectures
110 (cytochalasin B)
HN
O
HO
OH
O
O
HN
O OAc
OH
26 (L-696,474)
412 (periconiasin G)
HN
O O
HN
O O
HO
404 (periconiasin A)
202 (phenochalasin A)
O
O
HN
O
O
OH
O
HO
C–merocytochalasans
NH
O O
O
OH
O
OH
O
HO
448 (asperchalasine B)
NH
O O
O
OH
O
O
HO
OH
NH
O O
O
OH
O
O
HO
OH
450 (asperchalasine D)
449 (asperchalasine C)
Fig. 22 Typical structures of cytochalasans