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lidinyl CH2). 11: 6.73-7.23 (m, 4H, ArH), 3.80 (s, 3H, OCH3),
2.55-2.79 (m, 12H, benzylic CH2, NCH2), 2.34 (s, 3H, NCH3),
1.78 (m, 4H, pyrrolidinyl CH2). 12: 7.10 (d, J ) 8.7 Hz, 2H,
ArH2, ArH6), 6.82 (d, J ) 8.7 Hz, 2H, ArH3, ArH5), 3.78 (s, 3H,
OCH3), 2.50-2.75 (m, 12H, benzylic CH2, NCH2), 2.33 (s, 3H,
NCH3), 1.76 (m, 4H, pyrrolidinyl CH2). 13: 7.90 (d, J ) 7.5 Hz,
1H, ArH3), 7.52 (t, J ) 8.0 Hz, 1H, ArH5), 7.36 (m, 2H, ArH4,
ArH6), 3.07 (m, 2H, benzylic CH2), 2.50-2.74 (m, 12H, benzylic
CH2, NCH2), 2.36 (s, 3H, NCH3), 1.77 (m, 4H, pyrrolidinyl CH2).
14: 8.07 (d, J ) 8.4 Hz, 1H, ArH4, 1H, ArH2), 7.55 (d, J ) 6.8
Hz, 1H, ArH6), 7.45 (t, J ) 7.7, 1H, ArH5), 2.89 (m, 2H, benzylic
CH2), 2.69 (m, 2H, NCH2), 2.60 (m, 4H, pyrrolidinyl NCH2), 2.52
(m, 4H, NCH2), 2.34 (s, 3H, NCH3), 1.77 (m, 4H, pyrrolidinyl
CH2). 15: 8.14 (d, J ) 8.6 Hz, 2H, ArH3, ArH5), 7.36 (d, J ) 8.5
Hz, 2H, ArH2, ArH6), 2.89 (m, 2H, benzylic CH2), 2.68 (m, 2H,
NCH2), 2.60 (s, 4H, pyrrolidinyl NCH2), 2.53 (m, 4H, NCH2), 2.33
(s, 3H, NCH3), 1.77 (m, 4H, pyrrolidinyl CH2). 16: 7.01 (d, J )
7.5 Hz, 2H, ArH4, ArH6), 6.65-6.72 (m, 2H, ArH3, ArH5), 2.63-
2.72 (m, 4H, benzylic CH2), NCH2), 2.60 (s, 4H, pyrrolidinyl
NCH2), 2.51 (m, 4H, NCH2), 2.34 (s, 3H, NCH3) 1.76 (m, 4H,
pyrrolidinyl CH2). 17: 7.07 (t, J ) 8.3 Hz, 1H, ArH5), 6.60 (d,
J ) 7.8 Hz, 1H, ArH4), 6.53 (d, J ) 6.9 Hz, 1H, s, 1H, ArH2,
ArH6), 3.61 (s, 2H, NH2), 2.51-2.73 (m, 12H, benzylic CH2,
NCH2), 2.33 (s, 3H, NCH3), 1.77 (m, 4H, pyrrolidinyl CH2). 18:
6.99 (d, J ) 8.1 Hz, 2H, ArH2, ArH6), 6.62 (d, J ) 8.0 Hz, 2H,
ArH3, ArH5), 3.55 (s, 2H, NH2), 2.53-2.70 (m, 12H, benzylic CH2,
NCH2), 2.32 (s, 3H, NCH3), 1.76 (m, 4H, pyrrolidinyl CH2).
(27) de Costa, B. R.; Bowen, W. D.; Hellewell, S. B.; Walker, J . M.;
Thurkauf, A.; J acobson, A. E.; Rice, K. C. Synthesis and
evaluation of optically pure [3H](+)-pentazocine, a highly potent
and selective radioligand for σ receptors. Fed. Eur. Biochem.
Soc. 1989, 251, 53-58.
(26) The 1H NMR (CDCl3) δ of free base forms of compounds in Table
2: 4: 7.22 (t, J ) 6.9 Hz, 1H, ArH), 6.84-6.93 (m, 3H, ArH),
3.81 (s, 3H, OCH3), 3.71 (45%), 3.67 (55%) (s, 2H, benzylic CH2),
3.55 (55%), 3.45 (45%) (t, J ) 7.5 Hz, 2H, NCH2), 3.02 (55%),
2.97 (45%) (s, 3H, NCH3), 2.50-2.64 (m, 6H), 1.76 (m, 4H,
pyrrolidinyl CH2). 5: 7.23 (t, J ) 7.9 Hz, 1H, Ar-H5), 6.78-
7.20 (m, 3H, ArH), 3.79 (s, 3H, OCH3), 3.73 (45%), 3.69 (55%)
(s, 2H, benzylic CH2), 3.50 (55%), 3.48 (45%) (t, J ) 7.5 Hz, 2H),
3.01 (55%), 2.97 (45%) (s, 3H, NCH3), 2.47-2.66 (m, 6H), 1.77
(m, 4H, pyrrolidinyl CH2). 6: 7.16-7.20 (dd, J ortho ) 8.5 Hz,
J meta ) 3.6 Hz, 2H, ArH2, ArH6), 6.85 (d, J ) 8.7 Hz, 2H, ArH3,
ArH5), 3.79 (s, 3H, OCH3), 3.68 (44%), 3.64 (56%) (s, 2H, benzylic
CH2), 3.53 (56%), 3.43 (44%) (t, J ) 7.5 Hz, 2H, NCH2), 3.01
(56%), 2.96 (44%) (s, 3H, NCH3), 2.55 (m, 6H), 1.76 (m, 4H,
pyrrolidinyl CH2). 7: 8.09 (d, J ) 8.0 Hz, 1H, ArH3), 7.57 (t, J
) 7.5 Hz, 1H, ArH5), 7.43 (t, J ) 7.4 Hz, 1H, ArH6), 7.33 (d, J )
7.5 Hz, d, J ) 7.6 Hz, 1H, ArH4), 4.13 (40%), 4.04 (60%) (s, 2H,
benzylic CH2), 3.54 (m, 2H, NCH2), 3.17 (60%), 2.98 (40%) (s,
3H, NCH3), 2.77 (40%), 2.65 (60%) (t, J ) 7.5 Hz, 2H), 2.56 (m,
4H), 1.76 (m, 4H, pyrrolidinyl CH2). 8: 7.47-8.13 (m, 4H, ArH),
3.86 (44%), 3.81 (56%) (s, 2H, benzylic CH2), 3.56 (56%), 3.52
(44%) (t, J ) 7.1 Hz, 2H, NCH2), 3.50 (56%), 3.47 (44%) (s, 3H,
NCH3), 2.62-3.10 (m, 6H), 1.77 (m, 4H, pyrrolidinyl CH2). 9:
8.18 (d, J ) 8.6 Hz, 2H, ArH3, ArH5), 7.44 (d, J ) 8.5 Hz, 2H,
ArH2, ArH6), 3.86 (42%), 3.81 (58%) (s, 2H, benzylic CH2), 3.56
(58%), 3.46 (42%) (t, J ) 7.2 Hz, 2H, NCH2), 3.06 (58%), 2.99
(42%) (s, 3H, NCH3), 2.54-2.66 (m, 6H), 1.79 (m, 4H, pyrrolidinyl
CH2). 10: 6.82-7.20 (m, 4H, ArH), 3.81 (s, 3H, OCH3), 2.54-
2.83 (m, 10H, NCH2), 2.35 (s, 3H, NCH3), 1.77 (m, 4H, pyrro-
(28) Bowen, W. D.; de Costa, B. R.; Hellewell, S. B.; Walker, J . M.;
Rice, K. C. [3H](+)-Pentazocine: A potent and highly selective
benzomorphan-based probe for sigma-1 receptors. Mol. Neu-
ropharmacol. 1993, 3, 117-126.
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W.; Bowen, W. D. Rat liver and kidney contain high densities of
sigma-1 and sigma-2 receptors. Characterization by ligand
binding and photoaffinity labeling. Eur. J . Pharmacol., Mol.
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tions in some representative applications of aluminum hydride
for selective reductions. J . Am. Chem. Soc. 1968, 90, 2927-2938.
J M9600813