Medicinal Chemistry Research
ether:ethyl acetate = 50:1 to 1:1) and evaporated to obtain
the desired product. ESI-MS, 1H NMR, and 13C NMR
studies indicated that BQL2 (2.60 g, 4.46 mmol, 61.0%
yield, 95.9% purity) was obtained as a brown oil. 1H NMR:
(400 MHz, CDCl3-d) δ 8.48 (br d, J = 4.4 Hz, 2H), 8.35 (t,
J = 9.2 Hz, 2H), 8.18 (d, J = 8.6 Hz, 1H), 7.68 (dt, J = 1.3,
7.7 Hz, 1H), 7.64–7.57 (m, 3H), 7.55–7.46 (m, 3H),
7.46–7.38 (m, 1H), 7.10 (dd, J = 5.5, 6.6 Hz, 2H), 4.94 (t, J
= 6.5 Hz, 2H), 3.78 (s, 4H), 3.47 (s, 1H), 2.57–2.44 (m,
2H), 2.02–1.87 (m, 2H), 1.65–1.44 (m, 4H), 1.42–1.32 (m,
2H), 1.32–1.19 (m, 6H). 13C NMR: (101 MHz, CDCl3-d) δ
160.12, 158.63, 149.15–148.75 (m, 1 C), 147.29, 144.22,
136.37, 134.48, 130.59, 128.48 (d, J = 5.9 Hz, 1 C),
124.75, 123.48, 123.11, 122.84, 122.37 (d, J = 18.3 Hz, 1
C), 121.85, 121.38, 111.97, 72.95, 60.48, 54.53, 50.57,
30.09, 29.63–29.17 (m, 1 C), 27.19 (d, J = 24.9 Hz, 1 C),
25.91. ESI-MS: m/z = 559.3 for [M + H]+. Elemental ana-
lysis: calcd (%) for C36H38N4O2: C 77.39, H 6.86, N 10.03;
found: C 77.38, H 6.88, N 10.02.
Data for BQL2-Pt
Yield: 88.4%. ESI-MS: m/z = 788.0 for [M-Cl]+ ([Pt(BQL2)
Cl]+, 10 mM pH 7.35 Tris-HCl buffer solution, 5% DMSO).
Elemental analysis: calcd (%) for C36H38Cl2N4O2Pt: C 52.43,
1
H 4.64, N 6.79; found: C 52.42, H 4.67, N 6.78. H NMR
(500 MHz, DMSO-d6) δ 8.79 (dt, J = 6.0, 1.8 Hz, 2H),
8.32–8.24 (m, 4H), 8.17–8.11 (m, 1H), 7.83 (d, J = 7.9 Hz,
2H), 7.80–7.72 (m, 3H), 7.68–7.65 (m, 2H), 7.55 (dddd, J =
30.5, 8.0, 6.9, 1.2 Hz, 2H), 5.39 (d, J = 15.7 Hz, 2H),
4.95–4.81 (m, 4H), 3.03–2.98 (m, 2H), 1.84 (dq, J = 13.6,
6.7 Hz, 2H), 1.46 (q, J = 10.9, 7.2 Hz, 4H), 1.25 (t, J =
7.2 Hz, 2H), 1.16–1.07 (m, 6H). 13C NMR (126 MHz,
DMSO-d6) δ 166.36, 158.56, 149.47, 148.80, 147.24, 143.78,
141.78, 134.38, 131.72, 129.10, 128.95, 125.81, 125.57,
124.39, 123.93, 122.90, 122.49, 122.28, 121.20, 112.86,
73.06, 68.33, 64.68, 40.94, 40.53, 40.36, 40.20, 40.03, 39.86,
39.69, 39.53, 29.81, 29.09, 29.06, 28.90, 27.44, 26.24, 25.69.
Methods
Synthesis of BQL1-Pt and BQL2-Pt
A total of 1.0-mM cisplatin was prepared in 0.154-M NaCl
and DMSO solution [19]. For details on the methods and
materials used for BQL1-Pt (1.3 μM) and BQL2-Pt
(0.2 μM) preparation, please refer to the published meth-
ods of Qin, Liang, and Gou [29, 36]. In addition, detailed
procedures for other experimental methods are described in
the supplementary information.
The BQL1 or BQL2 ligand (1.0 mmol) and 1.0-mmol cis-
Pt(DMSO)2Cl2 were first dissolved in CH3OH-DMSO
solution (3.5 mL, v-v = 34:1) at 80 °C for 48 h, and the
final reaction mixture was allowed to cool overnight. After
filtration, the final solution was allowed to stand at 30 °C
for about 2 days, and the yellow solid powder suitable for
structural characterization was isolated, washed with
ethanol (EtOH) and diethyl ether, and air-dried.
Acknowledgements We thank the National Natural Science Founda-
tion of China (21867017) and the Natural Science Foundation of
Guangxi (2020GXNSFAA297077).
Data for BQL1-Pt
Compliance with ethical standards
Yield: 82.1%. ESI-MS: m/z = 731.9 for [M-Cl]+ ([Pt
(BQL1)Cl]+, 10 mM pH 7.35 Tris-HCl buffer solution,
5% DMSO). Elemental analysis: calcd (%) for
C32H30Cl2N4O2Pt: C 50.01, H 3.93, N 7.29; found: C
Conflict of interest The authors declare no competing interests.
Publisher’s note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations.
1
50.00, H 3.95, N 7.28. H NMR (500 MHz, DMSO-d6) δ
8.76 (dd, J = 5.8, 1.6 Hz, 2H), 8.29–8.22 (m, 3H), 8.20
(dd, J = 8.9, 1.2 Hz, 1H), 8.14–8.10 (m, 1H), 7.79 (d, J =
7.9 Hz, 2H), 7.78–7.72 (m, 3H), 7.65–7.60 (m, 2H), 7.57
(ddd, J = 8.2, 6.7, 1.2 Hz, 1H), 7.53 (ddd, J = 7.9, 6.5,
1.5 Hz, 1H), 5.41 (d, J = 15.9 Hz, 2H), 4.89 (d, J =
15.8 Hz, 2H), 4.79 (t, J = 6.1 Hz, 2H), 3.15–3.07 (m, 2H),
1.77 (dq, J = 12.2, 6.3 Hz, 2H), 1.65 (dq, J = 13.8, 7.1 Hz,
2H), 1.51 (q, J = 7.8 Hz, 2H). 13C NMR (126 MHz,
DMSO-d6) δ 166.34, 158.54, 149.44, 148.79, 147.20,
143.63, 141.73, 134.33, 131.75, 129.11, 128.93, 125.76,
125.61, 124.41, 123.91, 122.87, 122.51, 122.30, 121.12,
112.87, 72.78, 68.29, 64.57, 40.92, 40.51, 40.34, 40.18,
40.01, 39.84, 39.68, 39.51, 29.47, 27.13, 22.94.
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