Progress in the Chemistry of Cytochalasans
71
Aspergillus micronesiensis PG-1. Their structures were determined from the interpretation of the extensive spectroscopic data obtained and by single-crystal X-ray
diffraction. Plausible biosynthesis pathways of amichalasines D (456) and E (457)
were proposed involving a lactone aspochalasin unit. This is also the first report
of merocytochalasans containing a [5.6.12] lactone aspochalasin unit. Dimericchalasine A (469) [194] is a unique aspochalasin homodimer fused with a C-20/C-20
single bond. This compound was also isolated from Aspergillus micronesiensis PG-1
along with other mero-aspochalasins. Its structure and absolute configuration were
determined by means of X-ray crystallographic analysis. As far as is known by the
present authors, it is also the first cytochalasan homodimer.
2.5 The Alachalasin Group
The alachalasin group is a small group of cytochalasans (Table 20 and Fig. 20), with
only seven members, namely, alachalasins A–G (470–476) [12]. Alachalasins A–G
(470–476) were isolated from the cultures of Stachybotrys charatum by Che and
coworkers in 2008. This type of cytochalasan contains an alanine residue, and therefore, C-10 these compounds is a methyl group without any substitution. Alachalasins
F (475) and G (476) [12] possess an adenine moiety connected to C-19 of ring C,
and thus, they could also be considered to be merocytochalasans.
2.6 Trichalasin
From the culturing of Trichoderma gamsii isolated from the traditional Chinese
medicinal plant P. notoginseng, Zhou and coworkers isolated a series of cytochalasans
belonging to the aspochalasin group. Unexpectedly, an unusual cytochalasan named
trichalasin A (477) (Table 20 and Fig. 20) [9] was also isolated, which represents
Table 20 Alachalasins and trichalasin
Compound
Origin
References
Alachalasin A (470)
Stachybotrys charatum
[12]
Alachalasin B (471)
Stachybotrys charatum
[12]
Alachalasin C (472)
Stachybotrys charatum
[12]
Alachalasin D (473)
Stachybotrys charatum
[12]
Alachalasin E (474)
Stachybotrys charatum
[12]
Alachalasin F (475)
Stachybotrys charatum
[12]
Alachalasin G (476)
Stachybotrys charatum
[12]
Trichalasin A (477)
Trichoderma gamsii
[9]
71
Aspergillus micronesiensis PG-1. Their structures were determined from the interpretation of the extensive spectroscopic data obtained and by single-crystal X-ray
diffraction. Plausible biosynthesis pathways of amichalasines D (456) and E (457)
were proposed involving a lactone aspochalasin unit. This is also the first report
of merocytochalasans containing a [5.6.12] lactone aspochalasin unit. Dimericchalasine A (469) [194] is a unique aspochalasin homodimer fused with a C-20/C-20
single bond. This compound was also isolated from Aspergillus micronesiensis PG-1
along with other mero-aspochalasins. Its structure and absolute configuration were
determined by means of X-ray crystallographic analysis. As far as is known by the
present authors, it is also the first cytochalasan homodimer.
2.5 The Alachalasin Group
The alachalasin group is a small group of cytochalasans (Table 20 and Fig. 20), with
only seven members, namely, alachalasins A–G (470–476) [12]. Alachalasins A–G
(470–476) were isolated from the cultures of Stachybotrys charatum by Che and
coworkers in 2008. This type of cytochalasan contains an alanine residue, and therefore, C-10 these compounds is a methyl group without any substitution. Alachalasins
F (475) and G (476) [12] possess an adenine moiety connected to C-19 of ring C,
and thus, they could also be considered to be merocytochalasans.
2.6 Trichalasin
From the culturing of Trichoderma gamsii isolated from the traditional Chinese
medicinal plant P. notoginseng, Zhou and coworkers isolated a series of cytochalasans
belonging to the aspochalasin group. Unexpectedly, an unusual cytochalasan named
trichalasin A (477) (Table 20 and Fig. 20) [9] was also isolated, which represents
Table 20 Alachalasins and trichalasin
Compound
Origin
References
Alachalasin A (470)
Stachybotrys charatum
[12]
Alachalasin B (471)
Stachybotrys charatum
[12]
Alachalasin C (472)
Stachybotrys charatum
[12]
Alachalasin D (473)
Stachybotrys charatum
[12]
Alachalasin E (474)
Stachybotrys charatum
[12]
Alachalasin F (475)
Stachybotrys charatum
[12]
Alachalasin G (476)
Stachybotrys charatum
[12]
Trichalasin A (477)
Trichoderma gamsii
[9]