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HRMS and NMR spectrometry. 1H NMR (400 MHz) and 13C
NMR (100 MHz) spectra were measured by Bruker spectrometer
using tetramethylsilane (TMS) as an internal standard. Agilent
6510 Q-TOF LC/MS instrument (Agilent Technologies, Palo Alto,
CA) was used to measure molecular mass. UV-2550 UV/Vis
spectrophotometer (Hitachi Japan) and F-4600 uorescence
spectrophotometer (Hitachi Japan) were used to collect spec-
troscopic properties. The pH was measured using a FE 20/EL 20
pH meter (Mettler-Toledo Instruments (Shanghai) Co., Ltd.).
Fluorescent imaging was carried out by Olympus FV 1000-IX81
laser scanning confocal imaging.
Cell culture and uorescence imaging
HeLa cells for imaging were cultured in DMEM medium sup-
plemented with 10% (v/v) fetal bovine serum and penicillin/
streptomycin (100 mg mLꢀ1) in an atmosphere of 5% CO2 at
37 ꢁC. HeLa cells were incubated with JRQ (1 mM) for 30
minutes. HeLa cells were incubated with JRQN (1 mM) for 30
minutes, and then Cu2+ (5 mM) was added and incubated for
another 30 minutes. For co-localization experiments, RQN (1
mM) were incubated with 200 nM trackers (Mito-Tracker Green
(Mito), Golgi-Tracker Green (Golgi), ER-Tracker Green (ER), and
Lyso-Tracker Green (Lyso)) for 30 minutes, respectively; JRQN (1
mM) were incubated with 200 nM trackers (Mito-Tracker Green
(Mito), Golgi-Tracker Green (Golgi), ER-Tracker Green (ER), and
Lyso-Tracker Green (Lyso)) for 30 minutes, respectively, and
then treated with Cu2+ (5 mM) for another 30 min. Fluorescence
imaging was performed aer washing the medium three times
with PBS.
Synthetic procedures
Synthesis A, B and C. 4-Methoxy-1,2-phenylenediamine (A),
1,4-diethyl-6-methoxy-1,2,3,4-tetrahydroquinoxaline (B) and 2-
(2-hydroxyjulolidine) benzoic acid (C) were synthesized
according to reported method.6a,8
Synthesis of JRQ. The compound B (2.2 g, 10 mmol) and C
(3.7 g, 11 mmol) were dissolved in 5 mL methanesulfonic acid,
ꢁ
and then the reaction system was heated to 80 C and reacted
Conflicts of interest
under vigorous stirring for 8 hours. Aer cooling to room
temperature, the mixture was extracted with DCM (50 mL ꢂ 3)
and the collected organic layers were dried over anhydrous
Na2SO4. The crude product was obtained by concentration
under vacuum, and then puried by column chromatography to
afford the compound JRQ as a blue solid (4.1 g) in 81% yield. 1H
NMR (400 MHz, CDCl3) d 8.35–8.25 (m, 1H), 7.54–7.47 (m, 2H),
7.07–7.01 (m, 1H), 6.67 (s, 1H), 6.59 (s, 1H), 5.96 (s, 1H), 3.61 (s,
2H), 3.55 (dd, J ¼ 14.2, 7.1 Hz, 2H), 3.42–3.37 (m, 4H), 3.19 (s,
2H), 3.07–2.91 (m, 4H), 2.64–2.51 (m, 2H), 2.02 (d, J ¼ 5.0 Hz,
2H), 1.87 (d, J ¼ 5.7 Hz, 2H), 1.28 (t, J ¼ 7.1 Hz, 3H), 0.87 (t, J ¼
7.2 Hz, 3H). 13C NMR (100 MHz, CDCl3) d 166.59, 155.76, 153.64,
151.59, 149.71, 146.43, 134.50, 134.42, 133.19, 131.65, 131.24,
129.41, 129.38, 125.79, 123.50, 114.85, 113.87, 104.64, 104.05,
94.41, 50.72, 50.26, 48.02, 47.02, 45.43, 44.04, 27.72, 20.72,
20.05, 19.89, 10.99, 9.42. HRMS m/z ¼ 508.2600 calcd for
There are no conicts to declare.
Acknowledgements
This work was sponsored by the Natural Science Foundation of
China (NNSFC 21907075; 21272172), and the Natural Science
Foundation of Tianjin City (19JCZDJC32400; 18JCQNJC75900).
Notes and references
1 (a) M. Beija, C. A. M. Afonso and J. M. G. Martinho, Chem.
Soc. Rev., 2009, 38, 2410; (b) D. T. Quang and J. S. Kim,
Chem. Rev., 2010, 110, 6280; (c) X. Chen, T. Pradhan,
F. Wang, J. S. Kim and J. Yoon, Chem. Rev., 2012, 112,
1910; (d) Y. Yang, Q. Zhao, W. Feng and F. Li, Chem. Rev.,
2012, 113, 192; (e) K. P. Carter, A. M. Young and
A. E. Palmer, Chem. Rev., 2014, 114, 4564; (f) S. Cai, Y. Lu,
S. He, F. Wei, L. Zhao and X. Zeng, Chem. Commun., 2013,
49, 822.
2 (a) Z. Zhang and S. Achilefu, Org. Lett., 2004, 6, 2067; (b)
J. M. Baumes, J. J. Gassensmith, J. Giblin, J. J. Lee,
A. G. White, W. J. Culligan, W. M. Leevy, M. Kuno and
B. D. Smith, Nat. Chem., 2010, 2, 1025; (c) Q. Wang, X. Jiao,
C. Liu, S. He, L. Zhao and X. Zeng, J. Mater. Chem. B, 2018,
6, 4096; (d) C. Liu, X. Jia, S. He, L. Zhao and X. Zeng, Org.
Biomol. Chem., 2017, 15, 3947; (e) X. Jiao, C. Liu, Q. Wang,
K. Huang, S. He, L. Zhao and X. Zeng, Anal. Chim. Acta,
2017, 969, 49; (f) X. Wang, L. Cui, N. Zhou, W. Zhu,
R. Wang, X. Qian and Y. Xu, Chem. Sci., 2013, 4, 2936.
3 (a) Z. Q. Guo, S. Park, J. Yoon and I. Shin, Chem. Soc. Rev.,
2014, 43, 16; (b) R. Weissleder and V. Ntziachristos, Nat.
C
32H34N3O3 [M]+, found: 508.2609.
Synthesis of JRQN. Hydrazine hydrate (50 mL) was added to
the methanol solution (10 mL) of JRQ (1.02 g, 2 mmol), and then
the reaction system was heated to 50 ꢁC and reacted under
vigorous stirring for 6 hours. Aer cooling to room temperature,
the mixture was extracted with DCM (50 mL ꢂ 3) and the
collected organic layers were dried over anhydrous Na2SO4. The
crude product was obtained by concentration under vacuum,
and then puried by column chromatography to afford the
compound JRQN as a pale yellow solid (0.55 g) in 53% yield. 1H
NMR (400 MHz, CDCl3) d 7.96–7.87 (m, 1H), 7.46–7.36 (m, 2H),
7.14–7.04 (m, 1H), 6.34 (s, 1H), 6.03 (s, 1H), 5.62 (s, 1H), 3.56 (d,
J ¼ 0.6 Hz, 2H), 3.40–3.29 (m, 4H), 3.13 (d, J ¼ 7.6 Hz, 4H), 3.11–
3.05 (m, 2H), 3.03–2.85 (m, 4H), 2.49 (qd, J ¼ 15.9, 7.9 Hz, 2H),
2.08–1.98 (m, 2H), 1.86 (dt, J ¼ 12.0, 6.2 Hz, 2H), 1.20 (t, J ¼
7.0 Hz, 3H), 0.83 (t, J ¼ 7.0 Hz, 3H). 13C NMR (100 MHz, CDCl3)
d 166.25, 151.98, 149.03, 146.21, 143.53, 137.27, 132.32, 131.40,
129.79, 127.83, 123.94, 123.88, 122.87, 117.19, 107.70, 104.34,
104.24, 97.86, 66.90, 49.97, 49.51, 46.65, 45.74, 45.43, 45.35,
27.20, 22.02, 21.48, 21.28, 10.51, 9.61. HRMS m/z ¼ 522.2895
calcd for C32H35N5O2 [M + H]+, found: 522.2886.
ˇ
Med., 2003, 9, 123; (c) A. N. Butkevich, G. Lukinavicius,
E. D'Este and S. W. Hell, J. Am. Chem. Soc., 2017, 139,
12378; (d) L. Yuan, W. Y. Lin, K. B. Zheng, L. W. He and
W. M. Huang, Chem. Soc. Rev., 2013, 42, 622.
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RSC Adv., 2020, 10, 38038–38044 | 38043