(2H, dt, J 7 and 13, C(2)Hax and C(6)Hax), 3.80 (2H, br d, J 13,
C(2)Heq and C(6)Heq), 5.11 (2H, s, CH2Ph), 7.25–7.36 (5H,
m, aromatic); δC (63 MHz) 30.0 (q, CH3), 38.2 (t, C3 and C5),
40.2 (t, C2 and C6), 66.9 (t, CH2Ph), 67.7 (s, C4), 127.7 (d,
aromatic), 127.8 (d, aromatic), 128.3 (d, aromatic), 136.7 (s,
(APCI†) 250 (100%, M ϩ 1), 217 (3, M Ϫ OHCH3), 158 (7,
M Ϫ PhCH2).
Biohydroxylation of N-benzyloxycarbonyl-cis-2,6-dimethyl-
piperidine 5. Hydroxylated product 13 was isolated as a colour-
less oil (10 mg, 5%); δH (360 MHz) 1.25 (6H, d, J 7, 2 × CH3),
1.42–1.60 and 1.86–1.90 (5H, m, C(3)H2, C(4)OH and C(5)H2),
4.20 (1H, tt, J 11 and 4, CHOH), 4.49–4.57 (2H, m, C(2)Heq
and C(6)Heq), 5.14 (2H, s, CH2Ph), 7.23–7.38 (5H, m,
aromatic); δC (63 MHz, DEPT) 21.7 (q, 2 × CH3), 39.4 (t, C3
and C5), 47.2 (d, C2 and C6), 61.4 (d, CHOH), 66.9 (t, CH2Ph),
127.7 (d, aromatic), 127.8 (d, aromatic), 128.4 (d, aromatic);
m/z (EI) required 263.15214, found 263.15203, (FAB) 264
(M ϩ 1).
aromatic), 155.1 (s, C᎐O); m/z (EI) required 249.13649, found
᎐
249.13637, 249 (44%, Mϩ), 158 (14, M Ϫ PhCH2), 142 (16,
M Ϫ PhCH2), 91 (100, PhCH2).
Biohydroxylation of N-benzyloxycarbonyl-3-methylpiperidine
3. Three products 11a–c were isolated from this biohydroxyl-
ation, two of which (11a and 11c) were found to be very
closely related and thus difficult to separate. These two products
were separated by subjecting the mixture to acetylation condi-
tions (10 mol equiv. acetic anhydride, 5 mol equiv. pyridine and
catalytic dimethylaminopyridine) under which conditions one
of the products was acetylated 11c and one was left untouched
11a. The products were then separated by preparative HPLC.
Product 11a was isolated as a colourless oil (10 mg, 3%); δH
(360 MHz) 1.21 (3H, s, CH3), 1.49–1.79 (5H, m, C(3)OH,
C(4)H2 and C(5)H2), 2.96–3.03 (2H, br m, C(2)Hax and
C(6)Hax), 3.68 (1H, br s, C(2)Heq), 3.84 (1H, ddd, J 4.5, 4.5
and 13, C(6)Heq), 5.13 (2H, s, CH2Ph), 7.28–7.35 (5H, m,
aromatic); m/z (EI) required 249.13649, found 249.13725, 249
(5%, Mϩ), 114 (26, M Ϫ PhCH2OCO), 91 (100, PhCH2).
Hydroxylated product 11b was isolated as a colourless oil (10
mg, 3%); δH (360 MHz) 0.99 (3H, d, J 6.5, CH3), 1.43–1.59 (3H,
br m, three of C(3)H, C(4)OH and C(5)H2), 1.91 (1H, br dd,
J 3.5 and 13, C(3)H, C(4)OH or C(5)H), 2.53 (1H, br s, C(2)Hax
or C(6)Hax), 2.90 (1H, ddd, J 3, 12 and 14, C(4)H), 3.30 (1H, br
m, C(2)Hax or C(6)Hax), 4.05–4.13 (2H, br m, C(2)Heq and
C(6)Heq), 5.11–5.12 (2H, d, J 2, CH2Ph), 7.28–7.36 (5H, m,
aromatic); m/z (EI) required 249.13649, found 249.13616, 249
(8%, Mϩ), 158 (11, M Ϫ PhCH2), 142 (M Ϫ PhCH2O), 91
(PhCH2).
Biohydroxylation of N-benzyloxycarbonyl-2-ethylpiperidine
6. Hydroxylated product 14 was isolated as a colourless oil (130
mg, 45%); δH (360 MHz) 0.85 (3H, t, J 7.5, C(8)H3), 1.23–1.66
(5H, m, C(3)H, C(4)OH, C(5)H and C(7)H2), 1.92 (2H, dd,
J 2.5 and 12.5, C(3)H and C(5), 2.85 (1H, ddd, J 2.5, 12.5 and
12.5, C(6)Hax), 3.91 (1H, tt, J 4.5 and 11.5, CHOH), 4.16 (1H,
br d, J 12.5, C(6)Heq), 4.33 (1H, br m, C(2)Heq), 5.12 (2H, d,
J 2, CH2Ph), 7.25–7.37 (5H, m, aromatic); δC (90 MHz) 10.7 (q,
C8), 23.8 (t, C7), 35.0 (C3 and C5), 37.6 (t, C6), 52.8 (d, C2),
65.0 (t, CHOH), 67.0 (t, CH2Ph), 127.6 (d, aromatic), 127.8 (d,
aromatic), 128.3 (d, aromatic), 136.8 (s, aromatic), 155.4 (s,
C᎐O); m/z (EI) required 263.15214, found 263.15253, (APCi)
᎐
264 (12%, M ϩ 1), 220 (M Ϫ CH3CH2), 172 (7, M Ϫ PhCH2),
156 (23, M Ϫ PhCH2O), 91 (100, PhCH2).
Biohydroxylation
of
N-benzyloxycarbonyl-3,3-dimethyl-
piperidine 7. Hydroxylated product 15 was isolated as a colour-
less oil (134 mg, 48%); δH (250 MHz; 345 K) 0.89 (3H, s, C(7)H3
or C(8)H3), 0.95 (3H, s, C(7)H3 or C(8)H3), 1.51–1.64 (2H, m,
C(5)H and C(4)OH), 1.71–1.82 (1H, m, C(5)H), 2.85 (1H, d,
J 13.5, C(2)Hax), 3.12–3.23 (1H, m, C(6)Hax), 3.40 (1H, dd,
J 8.5 and 4.0, CHOH), 3.56 (1H, dd, J 1.5 and 13.5, C(2)Heq),
3.81–3.91 (1H, m, C(6)Heq), 5.13 (2H, s, CH2Ph), 7.24–7.36
(5H, m, aromatic); δH (63 MHz) 18.4 (q, C7 or C8), 24.2 (q, C7
or C8), 29.5 (s, C3), 35.8 (t, C5), 41.5 (t, C2 or C6), 52.6 (t, C2
or C6), 66.9 (t, CH2Ph), 74.7 (d, CHOH), 127.7 (d, aromatic),
127.8 (d, aromatic), 128.3 (d, aromatic), 136.7 (s, aromatic),
The O-acetylated product of 11c was isolated as a colourless
oil (5 mg); δH (360 MHz) 0.88 (3H, d, J 12.5, CH3), 1.67–1.93
(3H, br m, C(3)H and C(5)H2), 2.07 (3H, s, CH3CO2), 3.00–3.15
(1H, br m, C(2)Hax or C(6)Hax), 3.25–3.28 (1H, br m,
C(2)Hax or C(6)Hax), 3.70 (1H, br s, C(2)Heq or C(6)Heq),
3.75 (1H, ddd, J 4.5, 4.5 and 13.5, C(2)Heq or C(6)Heq), 5.01
(1H, ddd, J 3, 3 and 5, C(4)Heq), 5.12 (2H, d, J 2, CH2Ph),
7.28–7.39 (5H, m, aromatic); m/z (EI) required 291.14706,
found 291.14768; 291 (3%, Mϩ), 200 (11, M Ϫ PhCH2), 91 (100,
PhCH2).
155.4 (s, C᎐O); m/z required 263.15214, found 263.15254, 263
᎐
(10%, Mϩ), 172 (5, M Ϫ PhCH2), 128 (3, CO2CH2Ph), 91 (100,
CH2Ph), 77 (4, Ph).
Biohydroxylation of N-Benzyloxycarbonyl-2-methylpiperidine
4. Hydroxylated product 12a was isolated as a colourless oil
(20 mg, 7%); δH (250 MHz) 1.35 (3H, d, J 7, CH3), 1.46–1.91
(5H, m, C(3)H2, C(4)OH and C(5)H2), 3.34 (1H, ddd, J 5,
12.5 and 13.5, C(6)Hax), 3.90 (1H, ddd, J 3.5, 4 and 12.5,
C(6)Heq), 4.16 (1H, q, J 3, CHOH), 4.31–4.42 (1H, m,
C(2)Heq), 5.12 (2H, s, CH2Ph), 7.25–7.36 (5H, m, aromatic);
δC (90 MHz) 19.1 (q, CH3), 32.2 (t, C3 or C5), 33.5 (t, C3 or
C5), 36.4 (t, C6), 45.7 (d, C2), 64.7 (d, CHOH), 66.8 (t,
CH2Ph), 127.7 (d, aromatic), 127.8 (d, aromatic), 128.4 (d,
Acknowledgements
We are grateful to the BBSRC and Zylepsis Ltd. for funding
(to S. J. A. and G. G. respectively). We would also like to
acknowledge the assistance of Mr J. Millar and Dr D. Reed
with NMR studies.
† APCI = Atmospheric pressure chemical ionisation.
References
aromatic), 136.9 (s, aromatic), 155.2 (s, C᎐O); m/z (EI)
᎐
required 249.13649, found 249.136337, (FAB) 234 (4%,
M Ϫ CH3), 158 (15, M Ϫ PhCH2), 142 (31, M Ϫ PhCH2O),
114 (2, M Ϫ PhCH2CO2), 91 (100, PhCH2).
1 E. W. Weiler, M. Droste, J. Eberle, H. J. Halfmann and A. Weber,
Appl. Microbiol. Biotechnol., 1987, 27, 252.
2 R. A. Johnson, M. E. Herr, H. C. Murray, L. M. Reineke and G. S.
Fonken, J. Org. Chem., 1968, 33, 3195; R. Furstoss, A. Archelas and
B. Waegell, Tetrahedron Lett., 1981, 22, 445; W. Carruthers, J. D.
Prail, S. M. Roberts and A. J. Willetts, J. Chem. Soc., Perkin Trans.
1, 1990, 2854; C. F. Palmer, B. Webb, S. Broad, S. Casson,
R. McCague, A. J. Willetts and S. M. Roberts, Bioorg. Med. Chem.
Lett., 1997, 7, 1299.
3 G. S. Fonken and R. A. Johnson, in Chemical Oxidations with
Microorganisms, VCH, Germany, 1972.
4 R. A. Johnson, H. C. Murray, L. M. Reineke and G. S. Fonken,
J. Org. Chem., 1969, 34, 2279.
Hydroxylated product 12b was isolated as a colourless oil (20
mg, 7%); δH (360 MHz) 1.12 (3H, d, J 7, CH3), 1.43–1.78 (5H,
m, C(3)OH, C(4)H2 and C(5)H2), 2.79 (1H, ddd, J 3, 13 and
13.5, C(6)Hax), 3.74–3.80 (1H, m, CHOH), 3.95 (1H, br d,
J 12.5, C(6)Heq), 4.51 (1H, q, J 6.5, C(2)H), 5.12 (2H, s,
CH2Ph), 7.25–7.38 (5H, m, aromatic); δC (90 MHz) 9.2 (q, CH3),
24.0 (t, C5 or C4), 27.1 (t, C5 or C4), 37.6 (t, C6), 51.0 (d, C2),
67.0 (t, CH2Ph), 69.0 (d, CHOH), 127.7 (d, aromatic), 127.9
(d, aromatic), 128.4 (d, aromatic), 136.7 (s, aromatic), 155.3
5 K. Tadano, Y. Iimura and T. Suami, J. Carbohydr. Chem., 1985, 4,
129.
(s, C᎐O); m/z (EI) required 249.13649, found 249.13637,
᎐
J. Chem. Soc., Perkin Trans. 1, 1998, 3365–3370
3369