The induction of cell death by phosphine silver(I) thiocyanate complexes in
SNO-esophageal cancer cells.
Zelinda Humana, Apollinaire Munyanezab, Bernard Omondib, Natasha M Sanabriaa,b, Reinout
Meijboomb, Marianne J. Cronjéa
aDepartment
of Biochemistry, University of Johannesburg, PO Box 524, Auckland Park,
Johannesburg 2006, South Africa. mariannec@uj.ac.za
bResearch
Centre for Synthesis and Catalysis, Department of Chemistry, University of Johannesburg,
PO Box 524, Auckland Park, Johannesburg 2006, South Africa. rmeijboom@uj.ac.za
Supplementary information
Experimental
Synthesis of [AgSCN(PPh3)2]2 (1);
In a 100 cm3 round bottomed flask, solid AgSCN (0.1032 g, 0.62 mmol) was added to the solution of
triphenylphosphine (PPh3) (0.3161 g, 1.20 mmol) in ethanol (30 cm 3) and DMSO (30 cm 3). The
reaction mixture was heated under reflux for 5.5 hours. The solution was filtered hot and the ethanol
was evaporated. The solution was left to crystallize from which small white crystals were isolated.
Yield: 0.3181 g (74%). m.p.: 218-220
; Anal. Reqd. for C74H60Ag2N2S2P4: C, 64.36; H, 4.38; N, 2.02;
S, 4.64%. Found: C, 64.42; H, 4.71; N, 2.05; S, 4.69%. IR (ν in cm-1): 3046 (ν(aromatic, =C-H),w);
2090 (ν(SCN), s); 1539 (w) 1478, 1433 (ν(C=C aromatic), m); 1327, 1306 (w); 1183, 1157 (w); 1094,
1070 (asymm, m); 1025 (w); 996 (w); 743 (ν(aromatic, δ C-H), s); 692 (ν(aromatic, δ C-H, meta), s; 1H
NMR (400 MHz, CDCl3): δ (ppm) 7.32 (m, 30H, H-aromatic);
13C{H}
NMR (100 MHz, CDCl3): δ (ppm)
128.94 (d, δ1= 128.89, δ2= 128.98, 1J(P-C)=6.8 Hz, meta C); 130.20 (para C); 132.16 (d, δ1= 132.03,
δ2= 132.28, 1J(P-C)=18.8 Hz, ipso C); 133.82 (d, δ1= 133.73, δ2= 133.90, 1J(P-C)=12.8 Hz, ortho C);
31P{H}
NMR (161 MHz, CDCl3): δ (ppm) 8.29.
Synthesis of [AgSCN{P(4-MeC6H4)3}2]2 (2);
In a 100 cm3 round bottomed flask, 0.100 g of AgSCN (0.603 mmol) and 0.367 g (1.206 mmol) of
[P(4-MeC6H4)3] were dissolved in 30 cm3 of pyridine. The reaction mixture was stirred under reflux
overnight. After filtration, the pyridine solution was allowed to stand at room temperature and a solid
crashed out. The latter was collected and re-crystallized in acetonitrile. Yield: 0.314 g (58%). m.p.:
181
; Anal. Calcd. for C86H84Ag2N2S2P4: C, 66.67; H, 5.46; N, 1.81. Found: C, 66.62; H, 5.24; N,
1.65%. IR (ν in cm-1): 3014 (ν(=C-H),w); 2918, 2863 (ν(alkane, C-H, stretch), asymm, w) 2130-2069
(ν(SCN), m); 1642, 1597 (ν(C=C aromatic), m); 1497, 1445 (ν(C=C aromatic), m); 1396 (ν(CH3 bend),
m); 839-802 (ν(aromatic, C-H bend, meta), s); 708 (ν(aromatic, C-H bend, ortho), m). 1H NMR (CDCl3,
δ, 300 MHz): 2.47 (s, 3H); 7.22 (d, 2H); 7.35 (d, 2H);
13C{H}
NMR (CDCl3, δ, 75.5 MHz): 21.76;
129.00; 129.39; 134.22; 140.69; 31P{H} NMR (CDCl3, δ, 121.4 MHz): 7.48.
Synthesis of [AgSCN{P(4-FC6H4)3}2]2 (3);
This complex was synthesized by heating one equivalent of P(4-FC6H4)3 (0.335 g, 1.06 mmol) with
AgSCN (0.176 g, 1.06 mmol) in acetonitrile (10.0 cm 3) under reflux. Recrystallization from acetonitrile
produced colourless crystals suitable for X-ray diffraction. Yield: 0.410 g (97.1%); m.p.: 210-215
;
Anal. Calcd. for C74H48Ag2N2S2P4F12: C, 55.66; H, 3.03; N, 1.75. Found: C, 55.67; H, 3.26; N, 1.72%;
IR (ν in cm-1): 3029 (ν(=C-H), w); 2360 (ν(C-H), w); 2081 (ν(SCN), m); 1586, 1558, 1541 (ν(C=C
aromatic), asymm, s); 1492 (asymm, s) 1394 (ν(C=C aromatic), m); 1299, 1273, 1224, 1158; 1093 (s),
1043 (m) 1012 (s); 824 (ν(aromatic), asymm, s); 707 (ν(aromatic), asymm, s); 1H NMR (400 MHz,
CDCl3): δ (ppm) 6.940 (t); 7.280 (t);
135.73 (q); 169.05 (d);
31P{H}
13C{H}
NMR (100 MHz, CDCl3): δ (ppm) 116.36 (q); 128.22 (q);
NMR (161 MHz, CDCl3): δ (ppm) 2.82.
Synthesis of [AgSCN{P(4-ClC6H4)3}2]2 (4);
In a 100 ml round bottomed flask, 0.100 g of AgSCN (0.603 mmol) and 0.440 g (1.206 mmol) of [P(pClC6H4)3] were dissolved in 30 cm 3 of pyridine. The reaction mixture was stirred under reflux
overnight. After filtration, the pyridine solution was allowed to stand at room temperature for the
product to crystallize. A suitable crystal was collected for the crystal structure determination. The
crystallized product was also used for other characterizations. Yield: 0.467 g (76%). m.p.: 207
;
Anal. Calcd. for C74H48Ag2N2S2P4Cl12: C, 49.53; H, 2.70; N, 1.56; S, 3.57%. Found: C, 49.38; H, 2.81;
N, 1.62; S, 3.21%; IR ( v in cm -1): 3056 (ν(=C-H), wk); 2076 (ν(SCN), asymm, s); 1575, 1560, 1477
(ν(C=C aromatic), m); 1386 (m); 1298 (w); 1182 (w); 1099, 1080 (s); 1102 (s); 813 (s); 744
(ν(aromatic), s); 703 (ν(C-Cl), m); 1H NMR (CDCl3, δ, 300 MHz): 7.31 (d, 2H), 7.45 (d, 2H);
NMR (CDCl3, δ, 75.5 MHz): 129.66; 130.95; 135.36; 137.47;
3.27.
31P{H}
13C{H}
NMR (CDCl3, δ, 121.4 MHz):