52
steroids 7 2 ( 2 0 0 7 ) 50–59
appropriate solvent. The nicotinoyl, 2-methoxynicotinoyl,
isonicotinoyl and 6-methylpicolinoyl derivatives were syn-
thesized in a manner similar to the above. TLC and LC–ESI-MS
analyses revealed that the formation of other esters derived
from 2-methyl-6-nitrobenzoic anhydride was negligible.
Analysis calculated for C25H27O3N: C, 77.09; H, 6.99; N, 3.60.
Found: C, 76.92; H, 7.12; N, 3.43.
2.4.8. Estra-1,3,5(10)-triene-3,17ˇ-diyl
di-6-methylpicolinate (2b)
Colorless plates. Yield: 68% (Procedure-ii). mp 188.5–190 ◦C
(from AcOEt-hexane). UV: ꢀmax 273.6 nm (ε = 11,600), 218.6 nm
(ε = 20,200). 1H NMR ı: 1.00 (3H, s, 18-Me), 2.67 (3H, s, 3-
picolinoyl-Me), 2.71 (3H, s, 17-picolinoyl-Me), 5.03 (1H, t,
J = 8.4 Hz, 17␣-H), 6.96 (1H, d, J = 2.6 Hz, 4-H), 7.01 (1H, dd, J = 8.4
and 2.6 Hz, 2-H), 7.32–7.34 (2H, m, 1-H and 17-Me-picolinoyl-
5-H), 7.41 (1H, d, J = 7.7 Hz, 3-Me-picolinoyl-5-H), 7.71 (1H, t,
J = 7.7 Hz, 17-Me-picolinoyl-4-H), 7.78 (1H, t, J = 7.7 Hz, 3-Me-
picolinoyl-4-H), 7.88 (1H, d, J = 7.7 Hz, 17-Me-picolinoyl-3-H),
8.80 (1H, d, J = 7.4 Hz, 3-Me-picolinoyl-3-H). Analysis calculated
for C32H34O4N2: C, 75.27; H, 6.71; N, 5.49. Found: C, 75.18; H,
6.76; N, 5.34.
2.4.3. Estra-1,3,5(10)-trien-17-on-3-yl picolinate (1a)
Colorless prisms. Yield: 76% (Procedure-i), 87% (Procedure-ii). mp
218–220 ◦C (from AcOEt). UV: ꢀmax 266.6 nm (ε = 5600), 217.8 nm
(ε = 14,900). 1H NMR ı: 0.93 (3H, s, 18-Me), 7.00 (1H, d, J = 2.7 Hz,
4-H), 7.04 (1H, dd, J = 8.5 and 2.7 Hz, 2-H), 7.34 (1H, d, J = 8.5 Hz,
1-H), 7.57 (1H, dd, J = 7.7 and 4.8 Hz, picolinoyl-5-H), 7.93 (1H,
t, J = 7.8 Hz, picolinoyl-4-H), 8.28 (1H, d, J = 7.8 Hz, picolinoyl-3-
H), 8.86 (1H, d, J = 4.8 Hz, picolinoyl-6-H). Analysis calculated
for C24H25O3N: C, 76.77; H, 6.71; N, 3.73. Found: C, 76.52; H,
6.71; N, 4.03.
2.4.4. Estra-1,3,5(10)-triene-3,17ˇ-diyl dipicolinate (2a)
Colorless plates. Yield: 61% (Procedure-i), 74% (Procedure-ii).
mp 183.5–185 ◦C (from AcOEt-hexane). UV: ꢀmax 265.8 nm
(ε = 11,200), 218.6 nm (ε = 27,500). 1H NMR ı: 1.11 (3H, s, 18-Me),
5.08 (1H, dd, J = 9.2 and 7.2 Hz, 17␣-H), 6.98 (1H, d, J = 2.4 Hz,
4-H), 7.02 (1H, dd, J = 8.5 and 2.4 Hz, 2-H), 7.34 (1H, d, J = 8.5 Hz,
1-H), 7.50 (1H, dd, J = 7.6 and 4.8 Hz, 17-picolinoyl-5-H), 7.56 (1H,
dd, J = 7.7 and 4.6 Hz, 3-picolinoyl-5-H), 7.87 (1H, t, J = 7.8 Hz,
17-picolinoyl-4-H), 7.92 (1H, t, J = 7.8 Hz, 3-picolinoyl-4-H), 8.12
(1H, d, J = 7.8 Hz, 17-picolinoyl-3-H), 8.28 (1H, d, J = 7.8 Hz, 3-
picolinoyl-3-H), 8.82 (1H, d, J = 4.8 Hz, 17-picolinoyl-6-H), 8.85
(1H, d, J = 4.6 Hz, 3-picolinoyl-6-H). Analysis calculated for
2.4.9. Androst-5-en-17-on-3ˇ-yl 6-methylpicolinate (3b)
Colorless prisms. Yield: 71% (Procedure-ii). mp 225.5–227 ◦C
(from AcOEt). UV: ꢀmax 272.6 nm (ε = 5600), 223.0 nm (ε = 8300).
1H NMR ı: 0.90 (3H, s, 18-Me), 1.09 (3H, s, 19-Me), 2.66
(3H, s, picolinoyl-Me), 4.89–4.97 (1H, m, 3␣-H), 5.46 (1H, d,
J = 4.6 Hz, 6-H), 7.32 (1H, d, J = 7.8 Hz, Me-picolinoyl-5-H), 7.70
(1H, t, J = 7.8 Hz, Me-picolinoyl-4-H), 7.90 (1H, d, J = 7.6 Hz, Me-
picolinoyl-3-H). Analysis calculated for C26H33O3N: C, 76.62; H,
8.16; N, 3.44. Found: C, 76.53; H, 8.26; N, 3.39.
2.4.10. Androst-4-en-3-on-17ˇ-yl 6-methylpicolinate (4b)
Colorless prisms. Yield: 85% (Procedure-ii). mp 207–208.5 ◦C
(from AcOEt). UV: ꢀmax 234.0 nm (ε = 19,200). 1H NMR ı: 0.99
(3H, s, 18-Me), 1.21 (3H, s, 19-Me), 2.66 (3H, s, picolinoyl-
Me), 4.93 (1H, dd, J = 9.4 and 7.8 Hz, 17␣-H), 5.74 (1H, s, 4-H),
7.21 (1H, d, J = 7.8 Hz, Me-picolinoyl-5-H), 7.70 (1H, t, J = 7.8 Hz,
Me-picolinoyl-4-H), 7.86 (1H, d, J = 7.8 Hz, Me-picolinoyl-3-H).
C30H30O4N2: C, 74.67; H, 6.27; N, 5.81. Found: C, 74.51; H, 6.02;
N, 5.74.
2.4.5. Androst-5-en-17-on-3ˇ-yl picolinate (3a)
Colorless prisms. Yield: 73% (Procedure-ii). mp 287–289 ◦C (from
AcOEt). UV: ꢀmax 265.2 nm (ε = 4100), 219.0 nm (ε = 8500). 1H
NMR ı: 0.90 (3H, s, 18-Me), 1.10 (3H, s, 19-Me), 4.94–5.02 (1H, m,
3␣-H), 5.48 (1H, d, J = 5.1 Hz, 6-H), 7.51 (1H, dd, J = 7.6 and 4.6 Hz,
picolinoyl-5-H), 7.93 (1H, dt, J = 7.8 and 1.5 Hz, picolinoyl-4-
H), 8.28 (1H, d, J = 7.8 Hz, picolinoyl-3-H), 8.86 (1H, d, J = 4.3 Hz,
picolinoyl-6-H). Analysis calculated for C25H31O3N·1/4H2O: C,
75.43; H, 7.98; N, 3.52. Found: C, 75.77; H, 7.90; N, 3.55.
Analysis calculated for C26H33O3N: C, 76.62; H, 8.16; N, 3.44.
Found: C, 76.54; H, 8.18; N, 3.39.
2.4.11. Estra-1,3,5(10)-trien-17-on-3-yl nicotinate (1c)
Colorless prisms. Yield: 62% (Procedure-i), 81% (Procedure-ii). mp
207–209 ◦C (from AcOEt). UV: ꢀmax 264.4 nm (ε = 6200), 217.8 nm
(ε = 22,600). 1H NMR ı: 0.93 (3H, s, 18-Me), 6.96 (1H, d, J = 2.4 Hz,
4-H), 7.00 (1H, dd, J = 8.4 and 2.4 Hz, 2-H), 7.36 (1H, d, J = 8.4 Hz,
1-H), 7.48 (1H, dd, J = 7.8 and 4.8 Hz, nicotinoyl-5-H), 8.45 (1H,
t, J = 7.8 Hz, nicotinoyl-4-H), 8.86 (1H, dd, J = 4.9 and 1.7 Hz,
nicotinoyl-6-H), 9.39 (1H, d, J = 1.7 Hz, nicotinoyl-2-H). Analy-
sis calculated for C24H25O3N: C, 76.77; H, 6.71; N, 3.73. Found:
C, 76.54; H, 6.86; N, 3.97.
2.4.6. Androst-4-en-3-on-17ˇ-yl picolinate (4a)
Colorless prisms. Yield: 81% (Procedure-ii). mp 213–214.5 ◦C
(from AcOEt). UV: ꢀmax 240.4 nm (ε = 19,000). 1H NMR ı: 1.01 (3H,
s, 18-Me), 1.21 (3H, s, 19-Me), 4.98 (1H, dd, J = 8.6 and 7.8 Hz,
17␣-H), 5.77 (1H, s, 4-H), 7.50 (1H, ddd, J = 7.8, 3.7 and 1.0 Hz,
picolinoyl-5-H), 7.86 (1H, dt, J = 7.8 and 1.5 Hz, picolinoyl-4-
H), 8.10 (1H, d, J = 7.8 Hz, picolinoyl-3-H), 8.81 (1H, d, J = 3.9 Hz,
picolinoyl-6-H). Analysis calculated for C25H31O3N: C, 76.30; H,
7.94; N, 3.56. Found: C, 76.30; H, 8.02; N, 3.55.
2.4.12. Estra-1,3,5(10)-triene-3,17ˇ-diyl dinicotinate (2c)
Colorless plates. Yield: 71% (Procedure-i), 85% (Procedure-ii).
mp 183.5–185 ◦C (from AcOEt-hexane). UV: ꢀmax 264.2 nm
(ε = 9700), 218.8 nm (ε = 35,600). 1H NMR ı: 1.00 (3H, s, 18-
Me), 5.00 (1H, dd, J = 9.2 and 7.8 Hz, 17␣-H), 6.96 (1H, d,
J = 2.4 Hz, 4-H), 7.00 (1H, dd, J = 8.6 and 2.7 Hz, 2-H), 7.36 (1H, d,
J = 8.6 Hz, 1-H), 7.53 (1H, dd, J = 7.8 and 4.8 Hz, 17-nicotinoyl-5-
H), 7.56 (1H, dd, J = 7.8 and 4.8 Hz, 3-nicotinoyl-5-H), 8.47 (1H, t,
J = 7.8 Hz, 17-nicotinoyl-4-H), 8.51 (1H, t, J = 7.8 Hz, 3-nicotinoyl-
4-H), 8.82 (1H, dd, J = 4.9, 1.7 Hz, 17-nicotinoyl-6-H), 8.87 (1H,
dd, J = 4.9 and 1.7 Hz, 3-nicotinoyl-6-H), 9.27 (1H, d, J = 1.7 Hz,
2.4.7. Estra-1,3,5(10)-trien-17-on-3-yl 6-methylpicolinate
(1b)
Colorless prisms. Yield: 63% (Procedure-ii). mp 220–222 ◦C (from
AcOEt). UV: ꢀmax 274.6 nm (ε = 5400). 1H NMR ı: 0.93 (3H, s,
18-Me), 2.71 (3H, s, picolinoyl-Me), 6.98 (1H, d, J = 2.2 Hz, 4-H),
7.02 (1H, dd, J = 8.4 and 2.2 Hz, 2-H), 7.22 (1H, d, J = 8.4 Hz, 1-H),
7.41 (1H, d, J = 7.9 Hz, Me-picolinoyl-5-H), 7.78 (1H, t, J = 8.0 Hz,
Me-picolinoyl-4-H), 8.08 (1H, d, J = 8.0 Hz, Me-picolinoyl-3-H).