S. Dasari, S. Singh, Z. Abbas et al.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 256 (2021) 119709
were synthesized by following a generalized synthetic procedure
in which a hot methanolic solution of Eu(CF
.334 mmol) and Tb(CF SO (0.200 g, 0.330 mmol), Gd(NO
6H O, (0.200 g, 0.443 mmol), SmCl O (0.200 g, 0.548 mmol),
ꢁ6H
Dy(NO
3 3 3
SO ) (0.200 g,
0
3
3
)
3
3 3
) -
ꢁ
2
3
2
3
)
3
ꢁhydrate (0.200 g, 0.574 mmol), in 10 mL of boiling
methanol was added drop wise to 30 mL hot stirred methanolic
solution of dtntp (0.336 g, 0.334 mmol) (1), and (0.332 g,
0
.330 mmol) (2), (0.446 g, 0.443 mmol) (3), (0.552 g, 0.548 mmol)
(4), (0.577 g, 0.574 mmol) (5), pretreated with 3 equivalents of
NaOH for 30 min. The reaction mixture was refluxed for 12 h on
oil bath at 70 °C under nitrogen atmosphere. The solvent was evap-
orated in the reduced pressure and re-dissolved in the small
amount of MeOH and precipitated by the addition of Et
was then filtered and washed with 10 mL of hot MeOH, 10 mL of
Et O, and finally dried in vacuum over P 10. The complex 1 was
dissolved in DMF/MeOH and slow evaporation with addition of
Et O/MeCN at RT after couple of months yields a very small block
2
O. which
2
4
O
2
shaped yellowish single crystals were obtained suitable for X-ray
crystallography. The solid-state structure of complex 1 shows Eu
(
III) 9th coordination site is occupied by the DMF solvent due to
the solvent of crystallization.
[Eu(dtntp)(H O)] (1). Yield ~84% (0.463 g). ESI-MS (in DMF): m/
z (%) calcd. For [MꢂH
155.2958(50), 1157.2958(58), 1158.2958(20). Found: 1156.2974
Fig. 11. Cell viability plots of HeLa cells treated and incubated with complexes 1
and 2 for 4 h in the dark followed by irradiated to UV-A light at 365 nm (6 W) for 1 h
showing the photocytotoxicity activity.
2
+
2
O + H] , 1156.2958(100), 1154.2958(76),
1
the respective Ln(III) using the following modified Horrocks’ equa-
(
(
100), 1154.2844(74), 1155.2928(50), 1157.2986(57), 1158.3029
tions for Eu(ΙΙΙ) (1) and Tb(ΙΙΙ) (2), [34].
ꢂ1
21). FT-IR (KBr, cm ): 3405(w, br,
N-H ,
m ) 2923(m), 2850(m),
ꢀ
ꢁ
ꢀ
ꢁ
ꢂ
1
s 2
H
1
1
s 2
H
1
1602(vs,
(
1
m
asym (CO
2
)), 1517(s,
m
C=O(CONH) amide), 1469(s), 1442
qEu ¼ 1:2
ꢂ
ꢂ 0:25 ; q ¼ 5:0
ꢂ
ꢂ 0:06
O
ꢂ
Tb
vs), 1392(vs,
masym (CO
2
)) 1324(s), 1257(s), 1166(m), 1118(s),
O
s
D2
O
O
s
D2
092(vs), 1032(m), 993(m), 928(m), 838(vs), 792(vs), 516(m).
The overall emission quantum yields (
U
) of the complexes (1–2
ꢂ1
ꢂ1
UV–vis (aqueous-DMF) [kmax/nm (
e
/M cm )]: 284(61780), 294
/ms): 0.455 (H O), 1.087 (D O);
Hydration number (q) = 1.23 at 298 K.
and 4–5) were measured at 298 K using quinine sulfate as refer-
ence using the following equation:[45]
(
59500), 324(21800). Lifetimes (
s
2
2
2
[Tb(dtntp)(H O)] (2). Yield ~84% (0.328 g). ESI-MS (in DMF): m/
A
AIref
ref In
n
2
+
£overall ¼ £ref
z (%) calcd. For [MꢂH
O + H] , 1162.3013(100), 1163.3013(67),
2
ref
2
1
164.3013(23), 1165.3013(8). Found. 1162.3020(100), 1163.3035
ꢂ1
Where A, I and n denote the respective absorbance at kex, area under
the emission curve and refractive index of the solvent respectively.
The /ref represents the reference standard quinine sulfate solution
quantum yield.
(65), 1164.3029(23), 1165.3032(6). FT-IR (KBr, cm ): 3412(w, br,
ꢂ
m N-H), 2919(m), 2850(m), 1601(vs,
amide), 1470(s), 1441(vs), 1385(vs,
1185(m), 1118(s), 1097(vs), 1039(m), 993(m), 928(m), 838(vs),
92(vs), 518(m). UV–vis (aqueous-DMF) [kmax/nm (
284(60900), 294(58800) 324(21770). Lifetimes
O), 0.803 (D O); Hydration number (q) = 1.12 at 298 K.
[Gd(dtntp)(H O)] (3). Yield ~84% (0.328 g). ESI-MS (in DMF): m/
z (%) calcd. For [MꢂH
1159.2957(75), 1160.2957(80), 1162.2957(52), 1163.2957(70),
1164.2957(39), 1165.2975(13). Found: 1161.3004(100),
m
asym (CO )), 1518(s, mC=O(CONH)
2
m
sym (CO2 )) 1321(s), 1260(s),
ꢂ
ꢂ1
ꢂ1
7
e
/M cm )]:
4
.3. Synthesis and characterization
(s/ms): 0.654
(
H
2
2
0
0
0
00
Synthesis of Bis(4 -(4-aminophenyl)-2,2 :6 ,2 -terpyridine)
derivative of dtpa [dtpa(Aph-tpy)
minophenyl)-2,2 :6 ,2 -terpyridine (1.09 g, 3.36 mmol, 2 equiv)
and diethylenetriaminepentaacetic acid bisanhydride (600 mg,
2
0
+
2
(dtntp)]. A mixture of 4 -(4-a
2
O + H] , 1161.2957(100), 1158.2957(40),
0
0
00
1
7
.68 mmol, 1 equiv) in dry DMF (20 mL) was stirred overnight at
0 °C. Diethyl ether (100 mL) was added to the reaction mixture
1158.2976(35), 1159.3009(69), 1160.2975(80), 1162.2990(52),
ꢂ1
1163.3052(68), 1164.2996(38), 1165.3009(14). FT-IR (KBr, cm ):
ꢂ
at 0 °C, and the desired dtntp ligand precipitate formed were then
filtered and washed twice with 10 mL of Et O, and finally dried in
vacuum over P
3435(w, br,
m
(N-H), 2918(m), 2849(m), 1601(vs,
m
asym (CO
2
)),
2
1517(s,
m
C=O(CONH) amide), 1468(s), 1440(vs), 1384(vs,
m
sym
ꢂ
4
O
10 and to yields crystalline product.
(CO
2
)), 1321(s), 1259(s), 1184(m), 1118(s), 1092(vs), 1055(m),
ꢂ1
dtntp: Yield ~87% (1.478 g). FT-IR (KBr, cm ): 3418 (w, br,
m
N-
994(m), 929(m), 837(vs), 791(vs), 513(m). UV–vis (aqueous-DMF)
ꢂ1
ꢂ1
H
), 3264 (w), 3051(m), 2925(m), 2850(m), 1665 (vs,
acid), 1601 (s, C=O(CONH) amide I), 1584 (s,
521(s), 1467(s), 1441(vs), 1413(m), 1388(vs) 1318(m), 1254(s),
mC=O, CO free
[kmax/nm (
e
/M cm )]: 284(53800), 294(52500), 324(20950).
O)] (4). Yield ~85% (0.550 g). ESI-MS (in DMF):
m
mC=O(CONH) amide II),
[Sm(dtntp)(H
2
+
1
1
6
1
m/z (%) calcd. for [MꢂH
2
O + H] , 1155.2885(100), 1150.2885(52),
227(m), 1092(vs), 1039(m), 990(m), 893(m), 837(vs), 791(vs),
1151.2885(72), 1152.2885(84), 1153.2885(67), 1154.2885(30),
1156.2885(62), 1157.2885(98), 1158.2885(56), 1159.2885(18).
+
60(vs), 516(m). ESI-MS (in DMF): m/z (%) calcd. For [M+H] ,
006.4000(100), 1007.4000(66), 1008.4000(23), 1009.4000(6);
Found:
1155.2983(100),
1150.2997(48),
1151.2979(72),
found,
009.3909(6). Elemental analysis: Calcd. for C56
H, 5.11; N, 15.31. Found: C, 66.78; H, 5.07; N, 15.24. UV–vis (in
1006.4008(100),
1007.4078(63),
1008.4085(23),
1152.2916(79), 1153.2965(68), 1154.2937(32), 1156.3057(64),
ꢂ1
1
H
51
N
11
O
8
: 66.85;
1157.3070(96), 1158.2949(56), 1159.2423(21). FT-IR (KBr, cm ):
ꢂ
3435(w, br,
mN-H), 2924(m), 2852(m), 1603(vs,
masym (CO
2
)),
ꢂ1
ꢂ1
aqueous-DMF) [kmax/nm (
95(60600), 284(62500).
Synthesis and Characterization of [Ln(dtntp)(H
e
/M cm )]: 383(2040), 324(25300),
1518(s,
m
C=O(CONH) amide), 1468(s), 1441(vs), 1392(vs,
m
sym
ꢂ
2
(CO
2
)), 1325(s), 1263(s), 1187(m), 1118(s), 1092(vs), 1039(m),
2
O)] (Ln
993(m), 930(m), 837(vs), 791(vs), 517(m). UV–vis (aqueous-DMF)
ꢂ1
ꢂ1
(
(
III) = Eu(III), Tb(III), Gd(III), Sm(III), Dy(III)). Lanthanide(III) (Ln
III) = Eu(1), Tb(2), Gd(3), Sm(4), Dy(5), complexes of the dtntp
[kmax/nm (
e
/M
cm )]: 284(64400), 294(62200), 324(24500).
O), 0.387 (D O).
Lifetimes (
s
/ms): 0.268 (H
2
2
11