Cytotoxicity Studies of Platinum(II) Complexes
3
(600 MHz, DMSO-d6) δ 11.72 (s, 1H, –OH), 8.06 (d,
1H, J = 4.8 Hz, Pyr-H), 7.37 (t, 1H, J = 7.2 Hz, Pyr-
H), 7.00 (dd, 1H, J = 7.2 Hz, Ar–H), 6.98 (t, 1H,
J = 4.2 Hz, Pyr-H), 6.83 (d, 1H, J = 8.4 Hz, Pyr-H),
6.58 (t, 1H, J = 6.0 Hz, Ar–H), 6.42 (d, 1H,
J = 8.4 Hz, Ar–H), 5.06 (t, 1H, J = 6.0 Hz, NH–)
4.41 (d, 2H, J = 6.6 Hz, –CH2), 2.26 (s, 3H, –CH3);
m.p.: 148–156 °C; Anal. Calc. for C13H14N2O: C,
72.87; H, 6.59; N, 13.07; Found: C, 72.83; H, 6.57; N,
13.13%.
4-Methyl-2-{[(pyridin-2-ylmethyl)-amino]-methyl}-
phenol (4h). Yellow oil, yield 50.3%. IR: 1649 (N–
1
H), 1610 (C=N), 1253 (Ph–O), 879, 769, 628 cm−1; H
NMR (600 MHz, DMSO-d6) δ 8.51 (d, 1H, J = 4.8 Hz,
Pyr-H), 7.77 (t, 1H, J = 7.8 Hz, Pyr-H), 7.40 (d, 1H,
J = 7.8 Hz, Pyr-H), 7.27 (t, 1H, J = 5.4 Hz, Pyr-H),
6.90 (s, 1H, Ar–H), 6.87 (d, 1H, J = 7.8 Hz, Ar–H),
6.61 (d, 1H, J = 7.8 Hz, Ar–H), 3.80 (s, 2H, –CH2),
3.76 (s, 2H, –CH2), 2.17 (s, 3H, –CH3); Anal. Calc.
for C14H16N2O: C, 73.66; H, 7.06; N, 12.27; Found:
C, 73.61; H, 7.08; N, 12.29%.
4-tert-Butyl-2-(pyridin-2-ylaminomethyl)-phenol
(4d).
White solid, yield 18.3%. IR: 1617 (N–H),
4-tert-Butyl-2-{[(pyridin-2-ylmethyl)-amino]-
1578 (C=N), 1261 (ph–O), 826, 770, 737 cm−1; 1H
NMR (600 MHz, DMSO-d6) δ 10.44 (s, 1H, –OH),
7.95 (s, 1H, Pyr-H), 7.39 (t, 1H, J = 4.2 Hz, Pyr-H),
7.21 (s, 1H, Ar–H), 7.10 (s, 1H, Pyr-H), 6.69 (dd, 1H,
J = 5.4 Hz, Ar–H), 6.55 (d, 1H, J = 7.8 Hz, Pyr-H),
6.50 (d, 1H, J = 4.8 Hz, Ar–H), 4.30 (d, 2H, J = 3 Hz,
–CH2), 1.21 (s, 9H, –C(CH3)3); m.p.: 151–164 °C;
Anal. Calc. for C16H20N2O: C, 74.97; H, 7.86; N,
10.93; Found: C, 74.94; H, 7.88; N, 10.94%.
methyl}-phenol (4i). Yellow oil, yield 64%. IR: 1637
(N–H), 1560 (C=N), 1255 (Ph–O), 823, 757, 679 cm−1;
1H NMR (600 MHz, DMSO-d6) δ 8.52 (d, 1H,
J = 4.2 Hz, Pyr-H), 7.77 (t, 1H, J = 6.6 Hz, Pyr-H),
7.41 (d, 1H, J = 7.8 Hz, Pyr-H), 7.27 (t, 1H, J = 4.8 Hz,
Pyr-H), 7.11 (s, 1H, Ar–H), 7.08 (d, 1H, J = 8.4 Hz,
Ar–H), 6.65 (d, 1H, J = 8.4 Hz, Ar–H), 3.82 (s, 2H, –
CH2), 3.80 (s, 2H, –CH2), 1.23 (s, 9H, –C(CH3)3);
Anal. Calc. for C17H22N2O: C, 75.52; H, 8.20; N,
10.36; Found: C, 75.50; H, 8.19; N, 10.39%.
2,4-Dichloro-6-(pyridin-2-ylaminomethyl)-phenol
(4e).
White solid, yield 70.4%. IR: 1613 (N–H),
2,4-Dichloro-6-{[(pyridin-2-ylmethyl)-amino]-
1578 (C=N), 1220 (ph–O), 765, 722, 565 cm−1; 1H
NMR (600 MHz, DMSO-d6) δ 13.24 (s, 1H, –OH),
8.12 (d, 1H, J = 4.8 Hz, Pyr-H), 7.41 (t, 1H, J = 7.2 Hz,
Pyr-H), 7.31 (s, 1H, Ar–H), 7.09 (s, 1H, Ar–H), 6.67 (t,
1H, J = 6.6 Hz, Pyr-H), 6.51 (d, 1H, J = 8.4 Hz, Pyr-
H), 5.15 (t, 1H, J = 6.0 Hz, NH–), 4.43 (d, 2H,
J = 6.6 Hz, –CH2); m.p.: 156–162 °C; Anal. Calc. for
C12H10Cl2N2O: C, 53.55; H, 3.75; N, 10.41; Found: C,
53.47; H, 3.79; N,10.45%.
methyl}-phenol (4j). Yellow solid, yield 21.5%. IR:
1638 (N–H), 1560 (C=N), 1265 (Ph–O), 862, 759,
1
725 cm−1; H NMR (600 MHz, DMSO-d6) δ 8.56 (s,
1H, Ar–H), 7.81 (t, 1H, J = 7.2 Hz, Pyr-H), 7.40 (d,
1H, J = 7.8 Hz, Pyr-H), 7.35 (s, 1H, Ar–H), 7.32 (t,
1H, J = 5.4 Hz, Pyr-H), 7.13(s, 1H, Ar–H), 3.94 (s,
2H, –CH2), 3.86 (s, 2H, –CH2); m.p.: 157–168 °C;
Anal. Calc. for C17H19NO3: C, 55.14; H, 4.27; N,
9.89; Found: C, 55.12; H, 4.25; N, 9.93%.
Complexes synthesis
4-Bromo-2-{[(pyridin-2-ylmethyl)-amino]-methyl}-
phenol (4f). Yellow oil, yield 65%. IR: 1591 (N–H),
1570 (C=N), 1265 (Ph–O), 816, 755, 625 cm−1; 1H
NMR (600 MHz, DMSO-d6) δ 8.52 (d, 1H, J = 4.8 Hz,
Pyr-H), 7.77 (t, 1H, J = 7.8 Hz, Pyr-H), 7.42 (d, 1H,
J = 7.8 Hz, Pyr-H), 7.33 (s, 1H, Ar–H), 7.27 (t, 1H,
J = 3.6 Hz, Pyr-H), 7.22 (dd, 1H, J = 8.4 Hz, Ar–H),
6.70 (d, 1H, J = 8.4 Hz, Ar–H), 3.81 (s, 2H, –CH2),
3.77 (s, 2H, –CH2); Anal. Calc. for C13H13BrN2O: C,
53.26; H, 4.47; N, 9.56; Found: C, 53.22; H, 4.49; N,
9.58%.
Platinum complexes 5a-5j were synthesized with the
following method: K2PtCl4 (0.0482 mmol) was added
to a CH3OH/H2O (4 mL, v/v = 1/1) solution of reduced
Schiff bases 4a-4j (0.0461 mmol) in the room tempera-
ture, the mixture was adjusted to pH = 8–9 in the begin-
ning, then stirred for 24 h and the pH was down to
about 7. The solution was heated in vacuo and recrystal-
lized from CH3OH/CH2Cl2 under the protection of N2.
Pt[4-Bromo-2-(pyridin-2-ylaminomethyl)-phenol]Cl2
(5a).
Brown solid, yield 76.8%. IR: 1618 (N–H),
1577 (C=N), 1265 (ph–O), 609 (Pt–N=C), 480 (Pt–N)
cm−1; ESI-MS: 565.8963 [M + Na]+. 1H NMR
(600 MHz, DMSO-d6) δ 10.70 (s, 1H, –OH), 7.73 (d,
1H, J = 4.8 Hz, Pyr-H), 7.21 (t, 1H, J = 7.5 Hz, Pyr-
H), 7.26(s, 1H, Ar–H), 7.25 (d, 1H, J = 9.0 Hz, Ar–H),
6.85 (t, 1H, J = 5.4 Hz, NH–), 6.56 (d, 1H, J = 8.4 Hz,
Pyr-H), 6.50 (d, 1H, J = 8.4 Hz, Ar–H), 6.29 (t, 1H,
J = 6.0 Hz, Pyr-H), 4.30 (d, 2H, J = 5.4 Hz, –CH2);
m.p.: 250–265 °C; Anal. Calc. for C12H11BrCl2N2OPt:
C, 26.44; H, 2.03; N, 5.14; Found: C, 26.38; H, 2.06;
N, 5.17%. Λm = 54 S cm2 mol−1.
4-Chloro-2-{[(pyridin-2-ylmethyl)-amino]-methyl}-
phenol (4g). Yellow oil, yield 52.3%. IR: 1637 (N–
1
H), 1591 (C=N), 1266 (ph–O), 817, 756, 662 cm−1; H
NMR (600 MHz, DMSO-d6) δ 8.52 (d, 1H, J = 4.2 Hz,
Pyr-H), 7.77 (t, 1H, J = 7.8 Hz, Pyr-H), 7.42 (d, 1H,
J = 7.8 Hz, Pyr-H), 7.27 (t, 1H, J = 6.0 Hz, Pyr-H),
7.21 (s, 1H, Ar–H), 7.10 (dd, 1H, J = 8.4 Hz, Ar–H),
6.75 (d, 1H, J = 8.4 Hz, Ar–H), 3.81 (s, 2H, –CH2),
3.77 (s, 2H, –CH2); Anal. Calc. for C13H13ClN2O: C,
62.78; H, 5.27; N, 11.26; Found: C, 62.75; H, 5.26; N,
11.29%.