Molecules 2018, 23, 2588
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conditions were: capillary voltage 2.50 kV, cone volta◦ge 112 V, extractor cone 4.5 V, desolvation gas
◦
500 L/h, cone gas 10 L/h, desolvation temperature 400 C, and source temperature 150 C. Acquisition
mass range was monitored from 50 to 1800 Da. System control and data acquisition were performed
using MassLynx V 4.1 software.
General Procedure for the Synthesis 3a–d
In a Schlenk tube under an argon atmosphere, 0.08 mmol of the respective diaryldisulfide,
THF (7 mL), sodium borohydride (180
TPP-F20 (10
µ
mol; 6.8 mg), and ethanol (3 mL) were added. After 1 min,
◦
µ
mol; 10 mg) 1 was added, and the resulting mixture was stirred at 50 C for 15 min.
The reaction was quenched with 10 mL of water, and the aqueous layer was extracted with CH2Cl2.
The combined organic extracts were dried over MgSO4, filtered and evaporated to dryness. The crude
products were purified in a silica gel TLC for chromatographic purification, using hexane–ethylacetate
(70:20) as the eluent, affording the pure porphyrin 3a–d.
5,10,15,20-tetrakis[4-(phenylthio)-2,3,5,6-tetrafluorophenyl]porphyrin (3a). Physical state: purple solid.
Yield: 10.9 mg, 84%. 1H-NMR (600 MHz, CDCl3)
δ 8.91 (s, 8H), 7.70 (d, J = 6 Hz, 8H), 7.41–7.49
(m, 12H),
F ortho),
−
2.85 (s, 2H) ppm. 19F-NMR (565 MHz, CDCl3) δ −132.87 (dd, J1 = 22.6, J2 = 11.3 Hz,
−
136.29 (dd, J1 = 22.6, J2 = 11.3 Hz, F meta) ppm. HRMS-ESI: m/z calcd to to C68H30F16N4S4
[M + H]+; 1335.1176 found:1335.1223.
5,10,15,20-tetrakis[-(4-methylphenylthio)-2,3,5,6-tetrafluorophenyl]porphyrin (3b). Physical state: purple
solid. Yield: 12 mg, 92%. 1H-NMR (600 MHz, CDCl3)
δ 8.90 (s, 8H), 7.65 (d, J = 6 Hz, 8H), 7.29
(d, J = 6 Hz, 8H), 2.44 (s, 12H),
−
2.91 (s, 2H). 19F-NMR (565 MHz, CDCl3) δ −133.28 (dd, J1 = 28.2,
J2 = 11.3 Hz, F ortho),
−
136.49 (dd, J1 = 28.2, J2 = 11.3 Hz, F meta) ppm. HRMS-ESI: m/z calcd to
C72H38F16N4S4 [M + H]+; 1391.1802 found: 1391.1873.
5,10,15,20-tetrakis[4-(4-chlorophenylthio)-2,3,5,6-tetrafluorophenyl]porphyrin (3c). Physical state: purple
solid. Yield: 10.7 mg, 82%. 1H-NMR (600 MHz, CDCl3)
δ 8.90 (s, 8H), 7.66 (d, J = 6 Hz, 8H), 7.47
(d, J = 6 Hz, 8H),
−
2.89 (s, 1H). 19F-NMR (565 MHz, CDCl3) δ −132.80 (dd, J1 = 22.6, J2 = 11.3 Hz,
F ortho),
−
135.90 (dd, J1 = 22.6, J2 = 11.3 Hz, F meta) ppm. HRMS-ESI: m/z calcd to C68H26Cl4F16N4S4
[M + H]+; 1472.9588 found: 1472.9628.
5,10,15,20-tetrakis[4-(2-aminophenylthio)-2,3,5,6-tetrafluorophenyl]porphyrin (3d). Physical state: purple
1
solid. Yield: 12.9 mg, 93%. H-NMR (600 MHz, CDCl3)
δ 8.86 (s, 8H), 7.83–7.81 (m, 4H), 7.32–7.29
(m, 4H), 6.88–6.83 (m, 8H), 4.68 (s, 8H)
−
2.96 (s, 2H). 19F-NMR (565 MHz, CDCl3) δ −133.78 (dd,
J1 = 28.2, J2 = 11.3 Hz, F ortho),
−
136.53 (dd, J1 = 28.2, J2 = 11.3 Hz, F meta) ppm. HRMS-ESI: m/z calcd
to C68H34F16N8S4 [M + H]+; 1395.1612 found: 1395.1611.
4. Conclusions
The synthesis of thioaryl-porphyrins using a new synthetic protocol was disclosed.
The methodology enabled the preparation of four porphyrins in very-good to excellent yields under
soft conditions. The new compounds presented good photophysical properties to be considered as
photosensitizers for photodynamic therapy. Additionally, experimental and theoretical DNA interactive
assays were performed, showing an effective interaction between thioaryl-porphyrin hybrids and DNA.
Supplementary Materials: The following are available online. Experimental procedures, characterization of
compounds, DNA UV-vis absorption spectra, EB DNA emission fluorescence spectra.
Author Contributions: P.F., F.C., L.D., M.A.F.F. and O.E.D.R. designed and developed the synthesis of the
thioaryl-porphyrins. B.A.I. and C.H.d.S. performed the photophysical evaluations. P.A.N. and J.B.T.d.R. performed
the docking studies.