Progress in the Chemistry of Cytochalasans
27
2.1.4 seco-Cytochalasins
In 2008, Gu and coworkers reported six novel cytochalasins named cytochalasins
Z 10 –Z 15 (149–154) [87] from the marine-derived fungus, Spicaria elegans (Table 6
Table 6 Seco-cytochalasins
Compound
Origin
References
Cytochalasin Z 10 (149)
Spicaria elegans
[87]
Cytochalasin Z 11 (150)
Spicaria elegans
[87]
Cytochalasin Z 12 (151)
Spicaria elegans
[87]
Cytochalasin Z 13 (152)
Spicaria elegans
[87]
Cytochalasin Z 14 (153)
Spicaria elegans
[87]
Cytochalasin Z 15 (154)
Spicaria elegans
[87]
Cytochalasin Z 18 (155)
Aspergillus flavipes
[11]
Cytochalasin Z 19 (156)
Aspergillus flavipes
[11]
Cytochalasin Z 20 (157)
Aspergillus flavipes
[11]
Cytochalasin Z 21 (158)
Spicaria elegans KLA03
[80]
and Fig. 6). Notably, ring C of these compounds is cleaved with a hydroxy group
located at C-9. These are the first cytochalasins that contain an open chain, which is
strikingly different from previously reported cytochalasins. These seco-cytochalasins
possibly are derived from cyclic carbonate cytochalasins by means of hydrolysis.
This same research group reported the three additional seco-cytochalasins Z 18 –Z 20
(155–157) [11] from Aspergillus flavipes that inhabit the mangrove plant, Acanthus
ilicifolius, and two of them exhibit a carbonate group at C-9, which could be postulated as intermediates of seco-cytochalasins from cyclic carbonate cytochalasins.
Later, from the work of the same group, cytochalasin Z 21 (158) [80] was obtained
from Spicaria elegans by the OSMAC method via adding d-tryptophan during its
culturing procedure.
2.1.5 Mero-cytochalasins
As mentioned previously, mero-cytochalasans are a class of cytochalasans formed
by the dimerization or polymerization of one or more cytochalasan molecules
7,18-dihydroxy-19-O-(4-methyl-(6E),(8E)-hexadecadienoyl)-16,18-dimethyl-10phenyl-[11]-cytochalasa-6(12),(13E)-diene-1,21-dione (159) [44], isolated from
Microporellus subsessilis, could be considered as a mero-cytochalasin, as formed by
the esterization between a cytochalasin and a long-chain fatty acid. Phomachalasins
A–D (160–163) (Table 7 and Fig. 7) [88] are four intriguing mero-cytochalasins
discovered by Evidente and coworkers from Phoma exigua var. exigua in 2011.
Phomachalasin B (161), possessing an unusual [5.6.15] carbocyclic core, has an
27
2.1.4 seco-Cytochalasins
In 2008, Gu and coworkers reported six novel cytochalasins named cytochalasins
Z 10 –Z 15 (149–154) [87] from the marine-derived fungus, Spicaria elegans (Table 6
Table 6 Seco-cytochalasins
Compound
Origin
References
Cytochalasin Z 10 (149)
Spicaria elegans
[87]
Cytochalasin Z 11 (150)
Spicaria elegans
[87]
Cytochalasin Z 12 (151)
Spicaria elegans
[87]
Cytochalasin Z 13 (152)
Spicaria elegans
[87]
Cytochalasin Z 14 (153)
Spicaria elegans
[87]
Cytochalasin Z 15 (154)
Spicaria elegans
[87]
Cytochalasin Z 18 (155)
Aspergillus flavipes
[11]
Cytochalasin Z 19 (156)
Aspergillus flavipes
[11]
Cytochalasin Z 20 (157)
Aspergillus flavipes
[11]
Cytochalasin Z 21 (158)
Spicaria elegans KLA03
[80]
and Fig. 6). Notably, ring C of these compounds is cleaved with a hydroxy group
located at C-9. These are the first cytochalasins that contain an open chain, which is
strikingly different from previously reported cytochalasins. These seco-cytochalasins
possibly are derived from cyclic carbonate cytochalasins by means of hydrolysis.
This same research group reported the three additional seco-cytochalasins Z 18 –Z 20
(155–157) [11] from Aspergillus flavipes that inhabit the mangrove plant, Acanthus
ilicifolius, and two of them exhibit a carbonate group at C-9, which could be postulated as intermediates of seco-cytochalasins from cyclic carbonate cytochalasins.
Later, from the work of the same group, cytochalasin Z 21 (158) [80] was obtained
from Spicaria elegans by the OSMAC method via adding d-tryptophan during its
culturing procedure.
2.1.5 Mero-cytochalasins
As mentioned previously, mero-cytochalasans are a class of cytochalasans formed
by the dimerization or polymerization of one or more cytochalasan molecules
7,18-dihydroxy-19-O-(4-methyl-(6E),(8E)-hexadecadienoyl)-16,18-dimethyl-10phenyl-[11]-cytochalasa-6(12),(13E)-diene-1,21-dione (159) [44], isolated from
Microporellus subsessilis, could be considered as a mero-cytochalasin, as formed by
the esterization between a cytochalasin and a long-chain fatty acid. Phomachalasins
A–D (160–163) (Table 7 and Fig. 7) [88] are four intriguing mero-cytochalasins
discovered by Evidente and coworkers from Phoma exigua var. exigua in 2011.
Phomachalasin B (161), possessing an unusual [5.6.15] carbocyclic core, has an