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2671
1.70 (4H, dd), 3.90 (1H, m). 13C NMR (100 MHz, CDCl3) d (ppm):
4.6.4. (S)-MPA ester of 4-(1R-hydroxyethyl)cyclohexanone (S)-
11.7, 26.8, 32.5, 38.2, 67.4.
MPA-1e
1H NMR (400 MHz, CDCl3) d (ppm): 1.09 (3H, d, J = 6 Hz, H-8),
2.30 (1H, m, H-4), 2.37 (2H, m, H-6), 3.40 (3H, s, OMe), 4.75 (1H,
s, MPA-H), 4.92 (1H, q, J = 6 Hz, H-7), 7.30–7.42 (m, 10H, ArH).
4.5.8. 4-(1-Hydroxyethyl)cyclohexanol 1b9
Obtained as a colourless oil. 1H NMR (400Mhz, CDCl3) d (ppm):
1.16 (3H, d, J = 6.4 Hz, H-8), 1.71 (2H, m, H-3), 1.76 (2H, m, H-5),
1.97 (4H, m, H-2, H-6), 3.55 (1H, m, H-7), 3.67 (1H, t, J = 6.7 Hz,
H-1). 13C NMR (100 MHz, CDCl3) d (ppm): 20.8 (c, C-8), 26.3 (t, C-
3), 26.8 (t, C-5), 35.2 (t, C-2), 35.3 (t, C-6), 44.0 (d, C-4), 70.9 (d,
C-1), 71.6 (d, C-7).
4.7. Biotransformation of acetophenone 2
4.7.1. Biotransformation by B. cinerea
(a) Static culture: Acetophenone 2 was dissolved in ethanol and
then distributed in 12 Roux bottles after two days’ growth. The fer-
mentation was allowed to continue for five more days in six of the
bottles and 10 more days in the other six bottles. Chromatography
of the extract fermented for five days gave acetophenone 2
(4.2 mg), dihydrobotrydial24 (2.0 mg) and (S)-1-phenylethanol
4.5.9. trans-4-Ethyl-1-(1S-hydroxyethyl)cyclohexanol 1c
Obtained as a colourless oil. IR mmax (cmꢁ1): 3401, 2927, 2855,
1704, 1455, 1377, 960. 1H NMR (400 MHz, CDCl3) d (ppm): 0.88
(3H, t, J = 7.3 Hz, H-8), 1.07 (1H, m, H-4), 1.15 (3H, d, J = 6.4 Hz,
H-10), 1.24 (5H, m, H-7, H-3, H-5, H-6), 1.31 (1H, td, J = 13.4 Hz,
J = 3.8 Hz, H-2), 1.62 (3H, m, H-3’, H-5’, H-6’), 1.68 (1H, m, H-2’),
3.52 (1H, c, J = 6.4 Hz, H-9). 13C NMR (100 MHz, CDCl3) d (ppm):
11.5 (c, C-8), 17.1 (c, C-10), 27.5 (t, C-5), 27.6 (t, C-3), 29.6 (t, C-
7), 30.7 (t, C-6), 34.0 (t, C-2), 39.1 (d, C-4), 73.4 (s, C-1), 74.6 (d,
C-9). MS m/z 172.2 (M+), 154.1 [MꢁH2O]+, 127 (100), 109 (48),
67 (51). HRMS: calcd for C10H20O2: 172.1463; found 154.1339
[MꢁH2O]+.
(S)-2a (½a 2D5
¼ ꢁ47:0 (c 1.2, CHCl3)) (72.3 mg). Chromatography of
ꢂ
the extract fermented for 10 days gave dihydrobotrydial (4.3 mg)
and (S)-1-phenylethanol (S)-2a (½a D25
¼ ꢁ35:0 (c 1.5, CHCl3))
ꢂ
(50.0 mg). (b) Shaken culture: Acetophenone 2 was dissolved in
ethanol and then distributed in 10 flasks (500 mL) in an orbital
shaker after two days’ growth. The fermentation was allowed to
continue for two more days in five of the flasks and five more days
in the other five flasks. Chromatography of the extract fermented
for two days gave acetophenone 2 (12.0 mg) and (S)-1-phenyleth-
anol (S)-2a (½a 2D5
¼ ꢁ33:0 (c 2.1, CHCl3)) (45.0 mg). Chromatogra-
ꢂ
4.5.10. 4-(1-Hydroxyethyl)cyclohexanone 1e14
Obtained as a colourless oil. 1H NMR (400 MHz, CDCl3) d (ppm):
1.25 (3H, d, J = 6 Hz, H-8), 1.75 (1H, m, H-4), 2.03 (2H, m, H-3), 2.35
(2H, m, H-2), 2.40 (2H, m, H-6), 3.73 (1H, q, J = 6 Hz, H-7). 13C NMR
(100 MHz, CDCl3) d (ppm): 21.0 (c, C-8), 27.9 (t, C-5), 28.4 (t, C-3),
40.4 (t, C-2), 40.5 (t, C-6), 43.2 (d, C-4), 70.7 (d, C-7), 211.0 (s, C-1).
phy of the extract fermented for five days gave acetophenone (2)
(6.3 mg) and (S)-1-phenylethanol (S)-2a (½a D25
¼ ꢁ50:0 (c 1.4,
ꢂ
CHCl3)) (30.0 mg).
4.7.2. Biotransformation by T. viride
(a) Static culture: Acetophenone 2 was dissolved in ethanol and
then distributed in 18 Roux bottles after two days’ growth. The
fermentation was allowed to continue for five more days in twelve
of the bottles and for 10 more days in the other six bottles. Chro-
matography of the extract fermented for five days gave acetophe-
4.6. Mosher’s esters: general procedure
DMAP (3.96 mg, 2.0 equiv), DCC (7.0 mg, 2.1 equiv) and (R)-
MPA or (S)-MPA (6 mg, 2.25 equiv) were added to a stirred solution
of the corresponding compound, 1c or 1e (2.3 mg, 0.016 mmol) in
dry dichloromethane (1 mL) at room temperature. The resulting
mixture was stirred for 1–2 h. and was then concentrated under re-
duced pressure. The residue was chromatographed using a silica
gel column followed by HPLC purification to afford the desired
compounds (R)-MPA-1c, (S)-MPA-1c and (R)-MPA-1e, (S)-MPA-1e
with an average yield of 62%.
none 2 (9.3 mg), 6-pentyl-a-pyrone (100.0 mg), trichoviridine
(3.6 mg), (R)-1-phenylethanol (R)-2a (½a D25
¼ þ36:0 (c 1.0, CHCl3))
ꢂ
(60.0 mg) and tyrosol (3.6 mg). Chromatography of the extract
fermented for 10 days gave 6-pentyl-
a
-pyrone (62.0 mg) and (R)-
1-phenylethanol (R)-2a (½a D25
ꢂ
¼ þ34:0 (c 0.8, CHCl3)) (49.0 mg).
(b) Shaken culture: Acetophenone 2 was dissolved in ethanol and
then distributed in 10 flasks (500 mL) in an orbital shaker on a
PDB medium after two days’ growth. The fermentation was al-
lowed to continue for 5 more days in five of the flasks and for 10
more days in the other five flasks. Chromatography of the extract
fermented for five days gave acetophenone 2 (13.5 mg), 6-pentyl-
4.6.1. (R)-MPA ester of trans-4-ethyl-1-(1S-hydroxyethyl)cyclo-
hexanol (R)-MPA-1c
1H NMR (400 MHz, CDCl3) d (ppm): 0.86 (3H, t, J = 7.6 Hz, H-8),
1.05 (3H, d, J = 6.4 Hz, H-10), 1.21 (4H, m, H-3, H-5), 1.22 (2H, m, H-
7), 1.52 (1H, m, H-4), 1.54 (4H, m, H-2, H-6), 3.39 (3H, s, OMe), 4.77
(1H, c, J = 6.4 Hz, H-9), 4.78 (1H, s, MPA-H), 7.30–7.42 (m, 10 H,
ArH).
a
-pyrone (60.0 mg), trichoviridine (20.7 mg) and (R)-1-phenyleth-
anol (R)-2a (½a 2D5
¼ þ39:0 (c 1.7, CHCl3)) (72.0 mg). Chromatogra-
ꢂ
phy of the extract fermented for 10 days gave 6-pentyl-
a
-pyrone
(118.0 mg) and (R)-1-phenylethanol (R)-2a (½a D25
ꢂ
¼ þ36:0 (c 0.8,
CHCl3)) (90.0 mg).
4.6.2. (S)-MPA ester of trans-4-ethyl-1-(1S-hydroxyethyl)cyclo-
hexanol (S)-MPA-1c
4.7.3. Biotransformation by E. lata
(a) Static culture: Acetophenone 2 was dissolved in ethanol and
then distributed in 12 Roux bottles after seven days’ growth. The
fermentation was allowed to continue on surface culture for eight
more days in six of the bottles and for 15 more days in the other six
bottles. Chromatography of the extract fermented for eight days
1H NMR (400 MHz, CDCl3) d (ppm): 0.82 (3H, t, J = 7.2 Hz, H-8),
1.06 (1H, m, H-4), 1.16 (4H, m, H-3, H-5), 1.19 (3H, d, J = 6.4 Hz, H-
10), 1.21 (2H, m, H-7), 1.44 (4H, m, H-2, H-6), 3.39 (3H, s, OMe),
4.72 (1H, c, J = 6.4 Hz, H-9), 4.75 (1H, s, MPA-H), 7.30–7.42 (m,
10 H, ArH).
gave acetophenone
2 (38.0 mg), (S)-1-phenylethanol (S)-2a
(½a 2D5
¼ ꢁ9:0 (c 0.1, CHCl3)) (4.7 mg), 2-phenylethanol (6.8 mg)
ꢂ
4.6.3. (R)-MPA ester of 4-(1R-hydroxyethyl)cyclohexanone (R)-
MPA-1e
and tyrosol (2.1 mg). Chromatography of the extract fermented
for 15 days gave acetophenone 2 (38.0 mg) and (S)-1-phenyletha-
1H NMR (400 MHz, CDCl3) d (ppm): 1.24 (3H, d, J = 6 Hz, H-8),
1.71 (1H, m, H-4), 2.07 (2H, m, H-3), 2.14 (2H, m, H-2), 2.23 (2H,
m, H-6), 3.40 (3H, s, OMe), 4.74 (1H, s, MPA-H), 4.90 (1H, q,
J = 6 Hz, H-7), 7.30–7.42 (m, 10 H, ArH).
nol (S)-2a (½a 2D5
¼ ꢁ2:0 (c 0.1, CHCl3)) (11.0 mg). (b) Shaken culture:
ꢂ
Acetophenone 2 was dissolved in ethanol and then distributed in
10 flasks (500 mL) in an orbital shaker on a PDB medium after
two days’ growth. The fermentation was allowed to continue for