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6.70 (2s, ArH, 2H); 6.15 (d, J = 5.5 Hz, CH, 1H); 3.77, 3.73, 3.71, 6.70
(4s, 4OCH3,12H); 3.28 (s, NCH2, 2H); 3.20–3.01 (m, NCH2, 4H);
2.88–2.84 (t, CH2, 2H); 2.63 (s, NCH3, 3H); 2.20–2.12 (m, CH2,
4H); 2.06 (s, CH3, 6H); 1.60 (s, CH3, 3H); 1.51 (s, CH3, 3H); 1.32–
1.20 (m, CH, 1H); 1.09 (d, J = 6.5 Hz, CH3, 3H); 0.68 (d, J = 6.8 Hz,
CH3, 3H). Anal. Calcd for C36H56Cl2N3O6: C, 61.97; H, 8.09; N,
6.02. Found: C, 61.86; H, 8.01; N, 5.81.
5.5.7. N-(2-(3,4-Dimethoxyphenyl)-5-[[2-(3,4-dimethoxyphenyl)
ethyl]methylamino]-2-isopropyl-pentyl-2-(1-hydroxy-2,5,5-
trimethyl-pyrrolidin-2-yl)-acetamide HCl salt (18B)
Yield 440 mg 63%; white solid, mp 108–110 °C. 1H NMR (D2O):
6.98 (d, J = 8.3 Hz, ArH, 2H); 6.88 (d, J = 11.0 Hz, ArH, 2H); 6.82,
6.73, (2s, ArH, 2H); 3.80, (d, J = 2.3 Hz, OCH3, 3H); 3.75, (d,
J = 3.1 Hz, OCH3, 3H); 3.72, 3.67 (2s, 2OCH3, 6H); 3.50–3.47 (m,
CH2CO, 2H); 3.45 (s, NCH2, 2H); 3.33–3.19 (m, NCH2, 2H); 3.18–
3.04 (m, NCH2, 2H); 2.83–2.86 (t, CH2, 2H); 2.69 (s, NCH3, 3H);
2.05–1.98 (m, CH2, 2H); 1.85–1.72 (m, CH2, 2H); 1.42, 1.39, 1.30
(3CH3, 9H); 1.26–1.21 (m, CH, 1H); 1.20 (t, J = 7 Hz, CH2, 2H);
1.10 (t, J = 7,0 Hz, CH2, 2H); 0.78 (d, J = 6.8 Hz, CH3, 3H); 0.74 (d,
J = 5.6 Hz, CH3, 3H). Anal. Calcd for C36H58 l2N3O6: C, 61.79; H,
8.35; N, 6.00. Found: C, 61.68; H, 8.20; N, 5.82.
5.5.3. 1-Hydroxy-2,2,4,5,5-pentamethyl-2,5-dihydro-1H-pyrrol-
3-carboxylic acid-[(2-(3,4-di-methoxyphenyl)-5-[[2-(3,4-dimeth
oxyphenyl)ethyl]methylamino]-2-isopropyl-pentylamide HCl
salt (13B)
Yield 505 mg 71%; white solid, mp 123–125 °C. 1H NMR (D2O):
6.92 (s, ArH, 2H); 6.86 (d, J = 8.9 Hz, ArH, 2H); 6.76 (d, J = 9.1 Hz,
ArH, 2H); 3.77 (s, 2OCH3, 6H); 3.75 (s, 2OCH3, 6H); 3.65–3.55 (t,
NCH2, 2H); 3.30–3.25 (m, NCH2, 2H); 3.09–3.06 (t, NCH2, 2H);
2.92–2.88 (m, CH2, 2H); 2.83 (s, NCH3, 3H); 2.78 (s, CH3, 3H);
2.0–1.92 (m, CH2, 2H); 1.71–1.64 (t, CH2, 2H); 1.55, 1.42, 1.37,
1.34 (4s, 4CH3, 12H); 0.96–0.92 (m, CH, 1H); 0.76 (d, J = 6.6 Hz,
CH3, 3H); 0.72 (d, J = 5.5 Hz, CH3, 3H). Anal. Calcd for
C37H58Cl2N3O6: C, 62.44; H, 8.21; N, 5.90. Found: C, 62.25;H,
8.08; N, 5.74.
5.5.8. 1-Hydroxy-3-[(2-(3,4-dimethoxyphenyl)-5-[[2-(3,4-dime
thoxy-phenyl )ethyl]-methylamino]-2-isopropyl-pentylamino)
methyl]-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol, HCl salt (20B)
Yield 530 mg 73%; white solid, mp 122–124 °C. 1H NMR (D2O):
6.93 (d, J = 9.7 Hz, ArH, 2H); 6.82 (d, J = 6.1 Hz, ArH, 2H); 6.76 (s,
ArH, 2H); 5.20 (s, CH, 1H); 3.80, 3.78, 3.74, 3.73 (4s, 4OCH3, 12H);
3.69 (s, NCH2, 2H); 3.40 (s, NCH2, 2H); 3.38–3.30 (m, NCH2, 2H);
3.20–3.10 (m, NCH2, 2H); 2.84 (NCH3, 3H); 2.78 (t, CH2, 2H); 2.28–
2.18 (q, CH2, 2H); 1.87–1.80 (t, CH2, 2H); 1.55, 1.42, 1.48, 1.42 (4s,
4CH3, 12H); 1.28–1.20 (m, CH, 1H); 0.90 (d, J = 6.0 Hz, CH3, 3H);
0.79 (d, J = 5.9 Hz, CH3, 3H). Anal. Calcd for C36H59Cl3N3O5: C,
60.03; H, 8.26; N, 5.83. Found: C, 59.94; H, 8.19; N, 5.73.
5.5.4. 1-Hydroxy-2,2,5,5-tetramethyl-4-phenyl-2,5-dihydro-1H-
pyrrol-3-carboxylic acid-[(2-(3,4-dimethoxyphenyl)-5-[[2-(3,4-
dimethoxyphenyl)ethyl]methylamino]-2-isopropyl-pentylam
ide HCl salt (14B)
Yield 503 mg 65%; white solid, mp 121–123 °C. 1H NMR (D2O):
7.40 (d, J = 7 Hz, ArH, 2H); 7.33–7.30 (m, ArH, 2H); 7.10 (d, J = 6 Hz,
ArH, 2H); 6.94–6.86 (m, ArH, 4H); 6.63–6.56 (t, ArH, 1H); 3.78 (s,
OCH3, 6H); 3.77, 3.75 (2s, 2OCH3, 6H); 3.63–3.56 (t, NCH2, 2H);
3.49–3.42 (t, NCH2, 2H); 3.25 (s, NCH2, 2H); 2.96–2.89 (m, CH2,
2H); 2.80 (s, NCH3, 3H); 1.67–1.60 (m, CH2, 4H); 1.58, 1.48, 1.46,
1.40 (4s, 4CH3, 12H); 0.86–0.75 (m, CH, 1H); 0.59 (d, J = 7.2 Hz,
CH3, 6H). Anal. Calcd for C42H60Cl2N3O6: C, 65.19; H, 7.81; N,
5.43. Found: C, 64.99; H, 7.66; N, 5.29.
5.5.9. 2-(3,4-Dimethoxyphenyl)-5-[[2-(3,4-dimethoxyphenyl)
ethyl]-(1-hydroxy-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-
3-ylmethyl)-amino]-2-isopropyl-pentanenitrile HCl salt (23B)
Yield 525 mg 79%; white solid, mp 122–124 °C. 1H NMR (D2O):
6.95 (d, J = 7.2 Hz, ArH, 2H); 6.85 (d, J = 9.1 Hz, ArH, 2H); 6.72 (s,
ArH, 2H); 5.85 (s, CH, 1H); 3.77 (s, 2OCH3, 6H); 3.75, 3.74 (2s,
2OCH3, 6H); 3.38 (s, NCH2, 2H); 3.29–3.20 (t, NCH2, 2H); 3.17–
3.09 (t, NCH2, 2H); 2.90–2.80 (t, CH2, 2H); 2.22–2.10 (q, CH2, 2H);
1.98–1.90 (m, CH2, 2H); 1.43, 1.40, 1.37, 1.32 (4s, 4CH3, 12H);
1.30–1.20 (m, CH, 1H); 1.06 (d, J = 6.5 Hz, CH3, 3H); 0.63 (d,
J = 5.9 Hz, CH3, 3H). Anal. Calcd for C35H52Cl2N3O5: C, 63.15; H,
7.87; N, 6.31. Found: C, 63.07; H, 7.74; N, 6.15.
5.5.5. 1-Hydroxy-2,2,6,6-tetramethyl-1,2,3,6-tetrahydro-pyr-
idine-4-carboxylic acid-[(2-(3,4-dimethoxyphenyl)-5-[[2-(3,4-
dimethoxyphenyl)ethyl]methylamino]-2-isopropyl-pentyla-
mide HCl salt (16B)
5.5.10. 2-(3,4-Dimethoxyphenyl)-5-[[2-(3,4-dimethoxyphenyl)
ethyl]-(1-hydroxy-2,2,6,6-tetramethyl-1,2,3,6-tetrahydro
pyridin-4-ylmethyl)amino]-2-isopropyl-pentanenitrile HCl salt
(24B)
Yield 448 mg 63%; brownish white solid, mp 125–127 °C. 1H
NMR (D2O): 6.94 (d, J = 9 Hz, ArH, 2H); 6.87 (d, J = 8.6 Hz, ArH,
2H); 6.81, 6.73 (2s, ArH, 6H); 6.14 (s, CH, 1H); 3.76, 3.74 (2s,
4OCH3, 12H); 3.67 (s, NCH2, 2H); 3.28–3.16 (t, NCH2, 2H); 3.11–
2.98 (t, NCH2, 2H); 2.93–2.85 (m, CH2, 2H); 2.79 (s, NCH3, 3H);
1.96 (s, CH2, 2H); 1.76–1.65 (t, CH2, 2H); 1.60–1.54 (m, CH2, 2H);
1.50–1.40 (m, CH3, 12H); 1.20–1.11 (m, CH, 1H); 0.75 (d,
J = 6.6 Hz, CH3, 6H). Anal. Calcd for C37H58Cl2N3O6: C, 62.44; H,
8.21; N, 5.90. Found: C, 62.31; H, 8.15; N, 5.75.
Yield 468 mg 69%; white solid, mp 164–166 °C. 1H NMR (D2O):
6.93 (d, J = 9.5 Hz, ArH, 2H); 6.85 (d, J = 8.9 Hz, ArH, 2H); 6.72 (s,
ArH, 2H); 5.79 (s, CH, 1H); 3.77 (s, 2 OCH3,6H); 3.75, 3.74 (2s, 2
OCH3, 6H); 3.40 (s, NCH2, 2H); 3.27–3.20 (t, NCH2, 2H); 3.19–3.14
(t, NCH2, 2H); 2.89–2.80 (t, CH2, 2H); 2.23 (s, CH2, 2H), 2.20–2.10
(q, CH2, 2H); 1.96–1.90 (m, CH2, 2H); 1.45, 1.40, 1.39, 1.35 (4s,
4CH3, 12H); 1.24–1.16 (m, CH, 1H); 1.06 (d, J = 6.2 Hz, CH3, 3H);
0.66 (s, J = 6.0 Hz, CH3, 3H). Anal. Calcd for C36H54Cl2N3O5. C, 63.61;
H, 8.01; N, 6.18. Found: C, 63.44; H, 7.82; N, 6.02.
5.5.6. 1-Hydroxy-2,2,6,6-tetramethyl-piperidine-4-carboxylic
acid-[(2-(3,4-dimethoxyphenyl)-5-[[2-(3,4-dimethoxy-phenyl)
ethyl]-methyl-amino]-2-isopropyl-pentyl-amide HCl salt (17B)
Yield 428 mg 60%; pale yellow solid, mp 143–145 °C. 1H NMR
(D2O): 6.90 (d, J = 6.6 Hz, ArH, 2H); 6.84 (d, J = 6.9 Hz, ArH, 2H);
6.74 (s, ArH, 2H); 4.75–4.60 (m, CH, 1H); 3.76–3.73 (2s, 4OCH3,
12H); 3.65–3.55 (t, NCH2, 3H); 3.29–3.21 (t, NCH2, 2H); 3.10 (s,
NCH2, 2H); 2.90–2.83 (m, CH2, 2H); 2.81 (s, NCH3, 3H); 2.19–2.13
(t, CH2, 2H); 1.99–1.91 (d, CH2, 2H); 1.76–1.69 (m, CH2, 4H);
1.50, 1.39, 1.30, 1.28 (4s, 4CH3, 12H); 1.20–1.11 (m, CH, 1H);
0.99 (d, J = 6.8 Hz, CH3, 3H); 0.72 (d, J = 6.6 Hz, CH3, 3H). Anal. Calcd
for C37H60Cl2N3O6: C, 62.26; H, 8.47; N, 5.89. Found: C, 62.13; H,
8.38; N, 5.71.
5.6. Reduction of nitroxides to amines; general procedure(12A,
20A, 23A, 24A)
To a solution of nitroxide 12C or 20C or 23C or 24C (2.0 mmol) in
AcOH (10 mL) Fe powder (1.12 g, 20.0 mmol) was added and the
mixture was warmed up to 70 °C until the reaction started. The
mixture was stirred at room temperature for 1 h, diluted with water
(30 mL), decanted and the decanted aq solution made alkaline with
solid K2CO3 (intensive foaming!). The mixture was extracted with
CHCl3/MeOH (9:1) (3 Â 15 mL), dried (MgSO4), filtered, evaporated