M. Zhao et al. / Bioorg. Med. Chem. 15 (2007) 2815–2826
2821
6.85 (d, J = 8.1 Hz, 1H), 7.02 (s, 1H), 7.68 (s, 1H), 8.05
(s, 2H).
(KBr) 3325, 1600, 1535, 1365, 750 cmꢀ1
.
1H NMR
(DMSO-d6) d = 1.00 (s, 6H), 1.04 (s, 6H), 5.37 (s, 1H),
7.52 (d, J = 6.6 Hz, 1H), 7.60 (t, J = 7.8 Hz, 1H), 7.92
(t, J = 7.6 Hz, 1H), 8.05 (d, J = 7.2 Hz, 1H), 8.23 (s,
2H).
3.2.3.12. 1,3-Dihydroxyl-2-(40-N,N-dimethylphen-10-
yl)-4,4,5,5-tetramethylimidazolidine (1l). Using the
general procedure mentioned above 173 mg (31%) of
the title compound was obtained. Mp 168–169ꢁC.
Rf = 0.53 (CHCl3/CH3OH, 6:1). EI-MS (m/z) 279[M]+.
3.2.3.19. 1,3-Dihydroxy-2-(30-nitrophen-10-yl)-4,4,5,5-
tetramethylimidazolidine (1s). Using the general proce-
dure mentioned above 421 mg (75%) of the title
compound was obtained. Mp 179–181 ꢁC. Rf = 0.51
(CHCl3/CH3OH, 10:1). EI-MS (m/z) 281[M]+. IR
1
IR (KBr) 3345, 2840, 1595, 1450, 840 cmꢀ1. H NMR
(DMSO-d6) d = 1.03 (s, 6H), 1.05 (s, 6H), 2.85 (s, 6H),
4.01 (s, 1H), 6.68 (d, J = 8.7 Hz, 2H), 7.25 (d,
J = 8.7 Hz, 2H), 7.60 (s, 2H).
(KBr) 3315, 1530, 1360, 1600, 875, 790, 685 cmꢀ1. H
1
NMR (DMSO-d6) d = 0.52 (s, 12H), 4.19 (s, 1 H), 7.04
(dd, J = 8.7 Hz, J = 8.1 Hz, 1H), 7.34 (d, J = 6.0 Hz,
1H), 7.57 (d, J = 7.5 Hz, 1H), 7.77 (s, 1H), 8.03 (s, 2H).
3.2.3.13. 1,3-Dihydroxy-2-(20-fluorophen-10-yl)-4,4,
5,5-tetramethylimidazolidine (1m). Using the general
procedure mentioned above 366 mg (72%) of the title
compound was obtained. Mp 172–173ꢁC, Rf = 0.69
(CHCl3/CH3OH, 6:1), EI-MS (m/z) 254[M]+, IR
3.2.3.20. 1,3-Dihydroxy-2-(40-nitrophen-10-yl)-4,4,5,5-
tetramethylimidazolidine (1t). Using the general proce-
dure mentioned above 335 mg (63%) of the title
compound was obtained. Mp 172–174 ꢁC. Rf = 0.59
(CHCl3/CH3OH, 10:1). EI-MS (m/z) 281[M]+. IR
(KBr) 3325, 1532, 1590, 1500, 1450, 1365, 835, 790,
(KBr) 3310, 1600, 1130, 1235, 775 cmꢀ1 1H NMR
.
(DMSO-d6) d = 1.07 (s, 12H), 4.95 (s, 1H), 7.18 (t,
J = 8.4 Hz, 1 H), 7.30 (d, J = 8.1 Hz, 1H), 7.68 (d,
J = 8.7 Hz, 2H), 8.14 (s, 2H).
1
685 cmꢀ1. H NMR (DMSO-d6) d = 1.00 (s, 6H), 1.05
3.2.3.14.
1,3-Dihydroxy-2-(40-chlorophen-10-yl)-4,4,
(s, 6H), 4.71 (s, 1H), 7.70 (d, J = 9.0 Hz, 2H), 8.21 (d,
J = 7.2 Hz, 2H), 8.40 (s, 2H).
5,5-tetramethylimidazolidine (1n). Using the general pro-
cedure mentioned above 330 mg (61%) of the title com-
pound was obtained. Mp 213–215ꢁC. Rf = 0.73 (CHCl3/
CH3OH, 10:1). EI-MS (m/z) 270[M]+. IR (KBr) 3325,
3.2.4. General procedure for the preparation of 1-oxyl-2-
substitutedphenyl-3-oxide-4,4,5,5-tetramethyl-imidazoli-
dines (2a–t). The mixture of 250 mg (0.8 mmol) of 1,3-
dihydroxy-2-substitutedphenyl-4,4,5,5-tetramethylimi-
dazolidine and 0.5 g of lead dioxide in 80 ml methanol
was stirred at room temperature for 20 min and TLC
(CHCl3/CH3OH, 20:1) indicated the complete disap-
pearance of 1,3-dihydroxy-2-substitutedphenyl-4,4,5,5-
tetramethylimidazolidine. The reaction mixture was
filtered and the filtrate was evaporated under vacuum
to provide the title compound as dark blue crystals.
1600, 1500, 1085, 825 cmꢀ1
.
1H NMR (CDCl3)
d = 1.03 (s, 6H), 1.07 (s, 6H), 4.50 (s, 1H), 7.38 (d,
J = 8.7 Hz, 2H), 7.48 (d, J = 8.4 Hz, 2H), 7.80 (s, 2H).
3.2.3.15. 1,3-Dihydroxy-2-(40-bromophen-10-yl)-4,4,
5,5-tetramethylimidazolidine (1o). Using the general pro-
cedure mentioned above 320 mg (51%) of the title com-
pound was obtained. Mp 205–207 ꢁC. Rf = 0.69 (CHCl3/
CH3OH, 10:1). EI-MS (m/z) 314[M]+. IR (KBr) 3310,
1590, 1450, 1075, 830 cmꢀ1
.
1H NMR (CDCl3)
d = 1.14 (s, 12H), 4.77 (s,1H), 7.37 (d, J = 8.4 Hz, 2H),
7.47 (d, J = 7.8 Hz, 2H), 7.73 (s, 2H).
3.2.4.1. 1-Oxyl-2-(phen-10-yl)-3-oxide-4,4,5,5-tetrame-
thylimidazoline (2a). Using the general procedure men-
tioned above 74 mg (80%) of the title compound was
obtained. Mp 89–91 ꢁC. Rf = 0.85 (CHCl3/CH3OH,
20:1). EI-MS (m/z) 311[M]+. IR (KBr) 1600, 1450,
1357, 1070, 825 cmꢀ1. ESR: a five-line pattern with
intensity ratios of 1:2:3:2:1, aN = 8.16G, g = 2.00997.
3.2.3.16. 1,3-Dihydroxyl-2-(20,40-dichlorophenyl)-4,4,
5,5-tetramethylimidazolidine (1p). Using the general pro-
cedure mentioned above 427 mg (70%) of the title com-
pound was obtained. Mp 201–203ꢁC. Rf = 0.69 (CHCl3/
CH3OH, 10:1). EI-MS (m/z) 305[M]+. IR (KBr) 3315,
1
1590, 1450, 995, 820, 865 cmꢀ1. H NMR (DMSO-d6)
3.2.4.2. 1-Oxyl-2-(20-hydroxylphen-10-yl)-3-oxide-4,4,
5,5-tetramethylimidazoline (2b). Using the general proce-
dure mentioned above 111 mg (64%) of the title com-
pound was obtained. Mp 83–85 ꢁC. Rf = 0.75 (CHCl3/
CH3OH, 20:1). EI-MS (m/z) 217[M]+. IR (KBr) 3345,
1600, 1500, 1450, 760 cmꢀ1. ESR: a five-line pattern
with intensity ratios of 1:2:3:2:1, aN = 8.16G,
g = 2.00997.
d = 1.11 (s, 12H), 5.01 (s, 1H), 7.50 (d, J = 7.6 Hz,
1H), 7.52 (d, J = 8.1 Hz, 1H), 7.58 (s, 1H), 7.79 (s, 2H).
3.2.3.17. 1,3-Dihydroxyl-2-(30,40-dichlorophenyl)-4,4,
5,5-tetramethylimidazolidine (1q). Using the general pro-
cedure mentioned above 427 mg (70%) of the title com-
pound was obtained. Mp 212–214ꢁC. Rf = 0.69 (CHCl3/
CH3OH, 10:1). EI-MS (m/z) 305[M]+. IR (KBr) 3313,
1
1592, 1453, 992, 863, 822 cmꢀ1. H NMR (DMSO-d6)
3.2.4.3. 1-Oxyl-2-(30-hydroxylphen-10-yl)-3-oxide-4,4,
5,5-tetramethylimidazoline (2c). Using the general proce-
dure mentioned above 151 mg (76%) of the title com-
pound was obtained. Mp 137–139 ꢁC. Rf = 0.33
(CHCl3/CH3OH, 20:1). EI-MS (m/z) 249[M]+. IR
d = 1.06 (s, 12H), 4.99 (s, 1H), 7.66 (m, 3H), 7.92 (s, 2H).
3.2.3.18. 1,3-Dihydroxy-2-(20-nitrophen-10-yl)-4,4,5,5-
tetramethylimidazolidine (1r). Using the general
procedure mentioned above 410 mg (73%) of the title
compound was obtained. Mp 189–190ꢁC. Rf = 0.54
(CHCl3/CH3OH, 10:1). EI-MS (m/z) 281[M]+. IR
(KBr) 3340, 1590, 1450, 1380, 880, 800, 690 cmꢀ1
.
ESR: a five-line pattern with intensity ratios of
1:2:3:2:1, aN = 8.18 G, g = 2.00994.