Papini Grazia

New metal complexes supported by
scorpionate and macrocyclic ligands:
chemistry and biological studies
Dr.ssa Grazia Papini
School of Advanced Studies
Doctorate course in Chemical Sciences
Cycle XX
Scientific-Sector CHIM/03
Tutor
Prof. Giancarlo Gioia Lobbia
Well-known Scorpionate Ligands
Bis(pyrazolyl)borates
Tris(pyrazolyl)borates
Tetrakis(pyrazolyl)borates
“Nitrogen heterocycles other than pyrazole can be used, such as
imidazole, triazole, benzotriazole, thioimidazole, ecc.”
H
R5
H
R5
N
R4
H
N
N
R4
R5
B
B
N
R4
N
N
R4
R4
N
N
N
R5
Tris(imidazolyl)borates
N
H
N
R4
N
R4
N
Tetrakis(imidazolyl)borates
N
N N
H
N N
B
N
N
N
N N
N N
R5
R5
μ4-N4
Bis(imidazolyl)borates
N
B
N
R4
μ2-N,N’
R5
N
N
μ3-N,N’,N”
R4
N
R5
R5
B
H
N N
N
N
N
H
N
N N
B
N
N N
N
H
S
S
H
B
H
N N
N
N
N N
B
R
Poly(triazolyl)borates
N
N
2-S,S’
H
N
N
R
3-S,S’,B-H
Bis(3-R-2-thioxo-imidazolyl)borates
Poly(benzotriazolyl)borates
“Other modifications include changing the substituents on the heterocyclic ring.”
H
H
CF3
B
N
N
N
N
Na
O
N
O
O
N
O
S. Alidori, M. Pellei, C. Pettinari, C. Santini, B. W. Skelton, A. H. White,
Inorg. Chem. Commun., (2004). G. Bandoli, A. Dolmella, G. Gioia
Lobbia, G. Papini, M. Pellei, C. Santini Inorg. Chim. Acta (2006)
H
B
N
N
O2N
N
N
N
K+
N
[H3B(pzCF3)]H. V. R. Dias, S. Alidori, G. Gioia Lobbia, G. Papini, M.
Pellei, C. Santini Inorg. Chem. (2007)
Scorpionate ligands
with EWG
substituents
NO2
H
H
N
N
N
N
K+
NO2
H
[H2B(pzNO2)2]-
B
F3C
H
B
O2N
[H2B(tzNO2)2]M. Pellei, F. Benetollo, G.Gioia Lobbia,
S. Alidori, and C. Santini, Inorg. Chem., (2005)
H
H
[H2B(pzCOOEt,Me)2]-
H
H
B
N
N
N
N
K+
CF3
[H2B(pzCF3)2]-
M. Pellei, S. Alidori, G. Papini, G. Gioia
Lobbia, J. D. Gorden, H. V. Rasika Dias, C.
Santini, Dalton Trans. (2007)
“In addition, tripodal ligands can have central atoms other than boron, such as
carbon, phosphorus, or silicon….”
R
R
R5
C
N
N
R4
R5
N
R3
R3
N N
R
R5
N
N
N
R'
R4
Me Si
R
N
N
R3
O
P
R'
N
N
N
R'
R'
N N
N N
R'
R
R
R
N
R'
RC(pzx)3
RSi(pzx)3
(pzx)3PO
“…..and bearing a coordinating moiety (R') such as acetate, dithioacetate,
sulfonate, ethoxide, ”
O
C O
H
N
N
C
N
N
bdmpza
S
C S
H
N
N
C
N
N
bdmpzta
O
O S OLi
H
C
N
N
N
N
bdmpzs
Rhenium complexes
Versatile chemistry: several oxidation states accessible (from -I to VII); different
coordination numbers (from 4 to 8); various donor set available
 The similarity between technetium and rhenium chemistry, determined a
widespread use of the latter as a technetium surrogate to perform macroscopic
chemistry of potential radiopharmaceuticals. In this way, a ‘‘cold’’material (the
natural isotopic mixture of 185Re and 187Re) can be advantageously manipulated
instead of the radioactive nuclide 99gTc (t1/2 = 2.12 · 105 y, Eβ = 292 keV).
Rhenium has two β- emitters isotopes 186Re (β-max = 1.07 MeV; t1/2 = 90 h) and
188Re (βmax = 2.10 MeV; t1/2 = 17 h) which are of great interest to nuclear medicine
due to their physical and nuclear properties finalized to a potential application in
the radiopharmaceutical
The “metal - fragment” strategy
Linker
M
Labile groups
Stable building -block
Bioactive
molecule
Re(V) complexes
-
O
O
Cl
Cl
Re
Cl
N
Cl
N
Re
O
Cl
XY
Cl
N
X
Re
N
O
biomolecule
Y
O
O
Metal fragment
HN
NH
O
OH
S
O
C OLi
H
N
N
N N
CO2Na
N N
C
N
N
O
O S OLi
H
C
N
N
N
N
Metal Fragments
N
O
N
N
MeO Re O
MeO
N
Cl
N
O
C OLi
H
[ReOCl4][NBu4]
ROH(Et3N)
CO N
O N
N
Cl
Re
O
OR
[ReOCl4][NBu4]
[ReOCl4][NBu4]
MeOH
(Et3N)
N
CO N
O N
N
Cl
N
N
C
N
N
Cl
Re
Cl
O
N N
O
N N
OH
CH3CN
(Et3N)
O
O S OLi
H
C
N
N
N
N
[ReOCl4][NBu4]
ROH (Et3N)
N
N
Cl
SO2 N
O N
Re
OR
O
M. Porchia, G. Papini, C. Santini, G. Gioia Lobbia, M. Pellei, F. Tisato, G. Bandoli, A. Dolmella, Inorg. Chem. 44 (2005) 4045
Mixed coordination sphere complexes
N
N
H
) nO
2
CH
(
OH
3N
Cl
LiO
N
[ReOCl4][NBu4]
N
CH2Cl2 (Et3N)
E
N
N
O
E= CO,SO2
N
(CH2)n
N
Cl
N
E
O
N
Et3N
Re
N
OMe
O
H
(C
O
)n
H2
H
N
Et 3
M. Porchia, G. Papini, C. Santini, G. Gioia Lobbia,
M. Pellei, F. Tisato, G. Bandoli, A. Dolmella, Inorg.
Chem. 44 (2005) 4045
O
OH(CH2)nOH
O
n= 2, 3
O
OEt
N
E
O
Re
HO(CH2)nOH
Re
N
O
Et
N
N
N
E
O
N
N
Cl
N
E
O
Re
N
Cl
O
Structure of the complex
[Re(O)(bdmpza)(OCH2CH2O)]
Structure of the complex
[Re(O)(bdmpza)(OCH2CH2CH2O)]
CO N
O N
N
N
Re
Cl
OEt
O
HO
OC
(
Et
N
3
CH
2 )C
OO
H
N
CO N
O N
N
N
Re
Cl
Et3N
N
HOOC(CH2)COOH
O
O
CO N
O N
N
N
Cl
Re
H
C(
OO
O
)
CH 2
OH
CO
[ReOCl4][NBu4]
N N
CO2Li
CH2Cl2 (Et3N)
Re
OMe
N
Et 3
CO N
O N
HOOC(CH2)COOH
O
N N
O
O
Cl
O
Structure of the complex
[Re(O)(bdmpza)(mal)]
Marina Porchia,Grazia Papini, Carlo Santini, Giancarlo Gioia Lobbia, Maura Pellei, Francesco Tisato, Giuliano Bandoli,
Alessandro Dolmella Inorganica Chimica Acta 359 (2006) 2501–2508.
Potential Nitridorhenium complexes
H
H
B
:
N
:
N
N
R
:
R
N
R
N
Cl
:
NN
R
Re
R
Cl
Cl
H
H
B
N
:
N
N
N
R
R
H
B
N
N
:
:
N
:
R
N
N
Cl
N
:
N
R
H
N
N
N
:
N
B
N
N
N
N
R
Nitridorhenium precursors
N
Re
H2O2
H2O
Re2O7
[NBu4]OH
[NBu4][ReO4]
HCl g
Cl
NaN3
Re
Cl
Cl
Cl
N
Re
H2O2
H2O
Re2O7
HCl PPh3
EtOH
ReCl3PPh3
PPh3, [PhNHNH2]HCl
Ph3P
Cl
Re
Cl
PPh3
Pre-carbene ligands
H
N
KBH4
+
X
X
135°C
H
B
N
N
2
N
H
K+
X
N
N
2 BzBr
H
X
H
B
N
X
N
Br
-
N
N
Bz
Bz
H
2
H
B
N X
KBH4
+
3
N
H
170°C
B
X
N
N
N
N
X
+
K
X
3 BzBr
N
XN
X
N
N
2Br
XN
N
-
Bz
Bz
N
N
Bz
G. Papini, C. Santini, G. Gioia Lobbia, M. Pellei, G. Bandoli, A. Dolmella J. Organomet. Chem. (2008) submitted
R3
R
1
R2
+
O
R1
O
H
NH4Ac
+
R3
NH2
MeOH/H2O
H
O
R2
N
N
Liu J., Chen J., Zhao J., Zhao Y., Li L., Zhang H., Synthesis 17 (2003) 2661–2666.
Mes
H
H
+
O
O
1) CH3COOH, 75°C
H
2) Mes-NH2, NH4Ac
N
H
O
N
t-Bu
H
H
+
O
O
t
1) MeOH/H2O, 70°C
N
Bu-NH2
2) HCOH, NH3Ac
N
Mes
N
N
N
N
+ (CH3)2S.HBBr2
CH2Cl2
2Br -
B
24h
N
N
H
N
N
Mes
Mes
t-Bu
N
N
N
N
+ (CH3)2S.HBBr2
CH2Cl2
2Br -
B
24h
N
N
H
N
t-Bu
N
t-Bu
X
H
H
B
N
N
THF, n-BuLi
X
Br
X
N
:
N
Bz
Bz
N
Li +
- 78°C
N
N
B
X
-
H
:
H
N
Bz
Bz
[NBu4][ReNCl4]
H
H
2
B
B
N
N
2BrN
N
R
THF, n-BuLi
N
R
Li
:
N
:
- 78°C
R
N
R
N
N
R
N
N
:
N
R
R = Bz, t-Bu, Mes
+
MIXTURE OF
UNCHARACTERIZABLE
PRODUCTS
Silver(I) carbene complexes
H
R
B
N
N
N
N
R
N
Ag2O
2Br-
B
N
N
R
N
N
N
R
Ag
Ag
Ag
Br
CH2Cl2, 24h
H
R
N
N
R
N
R
N
N
N
R
R
N
N
B
R = Bz, t-Bu, Mes
H
Bz
Bz
H
N
B
N
N
H
N
N
Bz
Ag2O
Bz
N
N
H
H
B
B
CH2Cl2
N
Ag
N
N
Br
N
N
H
H
N
N
N
Ag
N
N
N
Bz
Bz
G. Papini, C. Santini, G. Gioia Lobbia, M. Pellei, G. Bandoli, A. Dolmella J. Organomet. Chem. (2008) submitted
Carbene transfer reactions
H
H
B
B
N
N
N
R
R
N
N
R
R
R
N
N
N
R
Au(SMe2)Cl
Ag
Ag
Ag
N
N
N
N
Br
Au
Au
Au
Br
CH2Cl2, 2h
R N
R
N
N
N
R
R
N
N
R N
N
N
N
N
R = Bz, t-Bu, Mes
B
B
H
H
Bz
Bz
N
N
Ag
H
H
Au(SMe2)Cl
H
CH2Cl2, 2h
H
Ag
N
N
N
Bz
Bz
B
B
H
H
N
N
N
N
N
H
B
N
Au
N
N
B
N
N
N
N
H
Bz
Bz
N
N
R
N
N
N
Au
N
N
N
Bz
Bz
G. Papini, C. Santini, G. Gioia Lobbia, M. Pellei, G. Bandoli, A. Dolmella J. Organomet. Chem. (2008) submitted
Rhenium derivatives
R
Bz
Bz
N
N
N
Ag
N
N
NBu4ReNCl4
H
H
CH2Cl2
N
N
Ag
H
N
N
Cl
H
N
R
N
N
R
R
N
Ag
R N
N
N
N
N
N
NBu4ReNCl4
R
Ag
Ag
N
Br
N
H
B
Cl
CH2Cl2
N
Re
R
N
N
N
B
R
N
H
N
R
N
N
R
B
H
N
N
R
H
B
N
Bz
N
N
Re
B
H
R
N
N
H
N
N
N
Bz
Re
B
H
N
Cl
N
N
N
N
N
H
B
B
H
N
N
R
R
N
N
N
R
N
Copper and Ruthenium derivatives
Bz
Bz
N
N
N
N
N
Cl
N
H
N
H
H
Ag
N
N
Bz
H
B
B
N
N
N
N
N
H
Bz
Bz
N
N
Cu
N
Ru
B
H
Bz
N
N
N
Cu
H
H
N
N
Bz
H
H
N
N
B
B
N
Bz
N
N
Ag
N
N
N
Bz
Bz
H
B
N
N
N
R
R
N
Ag
R N
R
Bz
N
N
N
R
Ag
Ag
N
N
R
N
N
N
Br
H
B
B
H
N
N
R
H
B
N
R
Ru
N
Bz
N
Cu
N
N
R
Cu
Cu
R N
N
N
N
N
B
N
Bz
Br
Cl
R
N
N
N
H
N
R
Copper derivatives
It is an essential trace metal for living organisms
Copper complexes’ activity is extremely wide
Copper has a well-documented coordination chemistry
Several radioactive copper isotopes are available nowadays for biomedical
purposes both for radioimaging and targeted radiotherapy
isotope
half-life
imaging
(emission, energy,
abundance)
Cu-60
20 min
PET
(b+, 873 keV, 93%)
Radiolabelling small molecules
Cu-61
3.3 h
PET
(b+, 527 keV, 62%)
Radiolabelling small molecules
Cu-62
9.7 min
PET
(b+, 1315 keV, 98%)
Radiolabelling small molecules
Cu-64
12.7 h
PET
(b+, 278 keV, 19%)
Radiolabelling small molecules,
peptides and antibodies
Cu-66
5.4 min
Cu-67
62.0 h
SPECT
(g, 185 keV, 48%)
therapy
(emission, energy, range in tissue)
application
(b-, 190 keV; 0.95 mm)
Radiolabelling small molecules
for therapy
(b-, 190 keV; 0.95 mm)
Radiolabelling small molecules,
peptides and antibodies
Fichna et al, Bioconjugate Chem., 14 (2003) 3-17
Copper(I) derivatives
C. Marzano, M. Pellei, D. Colavito, S. Alidori, G. Gioia Lobbia, V. Gandin, F. Tisato, and C. Santini, J. Med. Chem., 49
(2006) 7317
H
N
N
N
O2N
N
C=O
N
O
Cu
H
N
N
O2N
HO
N
C=O
N
O
Cu
HO
HO
HO
P
P
HOHO
OH
PF6
OHOH
OH
H
OH
N
N
NO2
P
Cu
HO
OH
P
P
HO
OH
P(CH2OH)3
H
N
N
H
N
C=O
N
O
Cu
P
HO
HO
N
N
N
P
OH
N
C=O
N
O
Cu
OH
HO
OH
HO
HO
OH
N
N
C=S
N
S
OH
OH
HO
P
HO
P
NCCH3
Cu
NO2
OH
HO
P
CH3CN
N
OH
HO
P
OH
HO
HO
P
OH
Cells line of ovarian carcinoma (2008) and cis-platino resistent carcinoma cells (C13)
OH
P
OH
OH
“CuP4” tipe species
[Cu(CH3CN)4][PF6] + 4 thp  [Cu(thp)4][PF6]
[Cu(CH3CN)4][PF6] + 2 bhpe  [Cu(bhpe)2][PF6]
HO
OH
HO
OH
P
HO
P
OH
Cu
HO
P
OH
OH
P
HO
P
OH
P
OH
Cu
HO
P
HO
HO
HO
HO
OH
P
OH
OH
[Cu(bhpe)2][PF6]
[Cu(thp)4][PF6]
31P-NMR
= - 5.35 (q), -145.14 (septet)
[Cu(thp)4]+ m/z = 560 (6)
[Cu(thp)3]+ m/z = 436 (65)
[Cu(thp)2]+ m/z =312 (100)
31P-NMR
= + 9.67 (dbr), - 144.05 (septet)
[Cu(bhpe)2]+ m/z = 492 (100)
C. Marzano, V. Gandin, M. Pellei, D. Colavito, G. Papini, G. Gioia Lobbia, M. Porchia, F. Tisato and C. Santini,
J. Med. Chem. 51 (2008) 798-808.
bhpe
O
P
O
O
Br
O O
P O
180°C
O O
P O
+
+
Br
O P
O O
O O
P O
+
Br
LiAlH4
HO
H2P
PH2
HCOH, HCl
EtOH
HO
HO
OH
P
P
OH
OH
NaHCO3
HO
OH
P
HO
P
OH
C. Marzano, V. Gandin, M. Pellei, D. Colavito, G. Papini, G. Gioia Lobbia, M. Porchia, F. Tisato and C. Santini,
J. Med. Chem. 1 (2008) 798-808.
Citotoxic activities
IC50 (µM) ± S.D.
Compound
HL60
A549
MCF-7
Daudi
HepG2
A375
CaCo2
HCT-15
HeLa
[Cu(thp)4][PF6]
0.60±0.02
9.11±2.71
11.08±0.52
6.94±0.18
1.26±0.10
4.58±2.41
1.08±0.12
2.00±0.03
8.21±1.50
[Cu(bhpe)2][PF6]
47.40±2.92
57.60±2.19
49.71±2.03
65.5±1.22
78.23±1.11
68.21±1.23
52.50±0.81
57.36±1.31
62.41±1.33
thp
68.63±2.44
72.91±2.44
64.23±4.29
>100
98.71±3.63
88.70±3.88
>100
>100
>100
bhpe
83.72±3.23
>100
>100
>100
71.71±1.64
73.21±1.22
84.11±2.22
91.71±4.01
>100
KPF6
>100
>100
>100
>100
>100
>100
>100
>100
>100
15.91±1.51
29.21±1.92
19.04±1.51
23.97±2.51
21.50±1.41
20.33±1.33
35.42±1.40
25.34±1.31
10.50±1.51
Cisplatin
IC50 values represent the drug concentrations that
reduced the mean absorbance at 570 nm to 50% of those
in the untreated control wells.
A549 = lung cancer
CaCo2, HCT-15 = colon cancer
Hela = cervix cancer
MCF-7 = breast cancer
HL60 = leukemia
Daudi = lymphoma
HepG2 = epatoma
A375 = melanoma
Human ovarian adenocarcinoma cells
Compound
2008
IC50 [µM]
C13
IC50 [µM]
R.F.
[Cu(thp)4][PF6]
1.48±0.21
2.88±1.07
1.9
Cisplatin
12.69±1.72
89.18±4.50
7.02
Human cervix squamous carcinoma cells
Compound
A431
IC50 [µM]
A431/Pt
IC50 [µM]
R.F.
[Cu(thp)4][PF6]
14.37±1.41
13.26±0.80
0.92
Cisplatin
22.06±1.62
57.76±1.81
2.61
Human colon adenocarcinoma cells
Compound
LoVo
IC50 [µM]
LoVo-MDR
IC50 [µM]
R.F.
[Cu(thp)4][PF6]
1.54±0.03
2.9±0.1
1.88
Doxorubicin
1.46±2.30
44.89±0.90
30.74
Cytotoxic activity of [Cu(thp)4][PF6]
onto three additional cell line pairs,
two of which (2008/C13* ovarian
cancer cells and A431/A431-Pt cervix
carcinoma cells) selected for their
resistance to cisplatin and one
(LoVo/LoVoMDR) for its resistance to
doxorubicin.
Cross-resistance profiles were
evaluated by means of the
resistance factor (RF), which is
defined as the ratio between IC50
values calculated for the resistant
cells and those arising from the
sensitive ones.
Comparison of IC50 values detected by MTT, NR and TB test after
incubation of 2008 cells with [Cu(thp)4][PF6] for different exposure times
TB test reveals damage to cell
membrane
MTT test mainly reflects damage to
mitochondria
The NR assay indicates damage to
lysosomes and Golgi apparatus
Lysosomes/Golgi apparatus are more sensitive to complex treatment. On the contrary,
the scarce permeability to vital dye indicates that plasma membrane function is still
maintained until the late phase of cell death. Lysosomal damage represents the early
cellular event associated with copper(I) complex cytototoxicity.
Cell cycle phases
G1 = GAP 1
S = Synthesis (DNA replication)
G2 = GAP 2
M = mitosis (nuclear and cytoplasmic division)
I = Interphase
3h
3h
12 h
12 h
24 h
24 h
48 h
48 h
----------2008 untreated cells
24h
48h
----------2008 cells treated with IC50 of [Cu(thp)4][PF6]
Ctr
Complex 3
p-Value
Ctr
Complex 3
p-Value
Apoptosis
%
4.24±0.71
2.43±0.66
<0.001
1.21±0.73
15.39±0.96
<0.001
G1 %
70.92±1.82
60.9±1.35
<0.001
65.57±1.21
41.03±1.39
<0.001
G2/M%
20.29±1.11
33.5±1.28
<0.001
32.62±1.46
37.03±1.12
<0.001
Percentage of cells in different cell cycle
phases as function of time exposure of
[Cu(thp)4][PF6], vs control untreated cells
Forward scattering (index of cell size) vs side
scattering (index of cell granularity) as a function
of time in 2008 cells
Mitochondrial energization of treated tumor
cells as the retention of a mitochondrial
selective cationic fluorescent probe,
tetramethyl rhodamine methyl ester (TMRM).
Flow cytometric profiles of
2008 cells untreated (panel
A) and treated with 3.125
(panel B) or 6.25 (panel C)
µM of copper(I) complex for
24 h and stained with
TMRM (10 nM).
Copper(I) complex induced
a massive increase of the
TMRM fluorescence
reflecting a dramatic
alteration of mitochondrial
membrane potential that
might be correlated with the
induction of a G2/M phase
cell cycle arrest.
----------2008 untreated cells
----------2008 cells treated with IC50 of [Cu(thp)4][PF6]
The coordination of mono-phosphine ligands to copper(I) gives rise to a metallodrug
able to inhibit the growth of tumor cells via cell G2/M cell cycle arrest and paraptosis
accompanied with the loss of mitochondrial transmembrane potential.
Potential Cu(I) radiopharmaceuticals
N
N
N
TPA
64Cu(II)Cl
Sodium acetate
buffer
N
P
N N
P
64
Cu
2
Sodium acetate
buffer
P
P
N
N
N
N N
N
(2)
THP
In vitro cell experiments
10.0
HO
OH HO
P
64
Cu
2
OH
P
HO
HO
HO
% Cell Associated Radioactivity
OH
OH
P
P
OH
OH HO
(1)
Sodium acetate
buffer
Ligand
8.0
6.0
4.0
4
2.0
1
3
0.0
0
CO2
CO2
20
40
60
80
100
120
Time (min)
N
N
N
64
Cu
HO
HO
N
N
P
OH
P
OH HO
(3)
N
N
OH
N
64
Cu
HO
HO
N
N
P
OH
P
OH HO
(4)
OH
Cell uptake behavior of complexes 1-4 into EMT-6
mammary carcinoma cells. Error bars not seen
are within symbols.
Biodistribution Studies
OH
The uptake and retention of activity was high
in many non-target tissues lung and liver
P
HO
35.0
HO
P
64
HO
40.0
Poor blood clearance suggestes breakdown
of the complex and binding of 64Cu to serum
proteins in vivo.
Cu
P
OH
1 hour
4 hour
OH
P
24 hour
OH
OH HO
30.0
%ID/g
The heart uptake was high at all time points
and there was no clearance from the
myocardium over 24 h post-injection
potentially due to the
monocationic nature of the complex
HO
45.0
OH HO
25.0
20.0
15.0
Tumor uptake of complex 1 was highest at 1
h and decreased slowly over 24 h. In the
same EMT-6 tumor model, uptake of 64CuATSM and 64Cu-PTSM (both of which are
clinically tested agents) into the tumor at 40
min post-injection showed lower uptake than
that of 1
10.0
5.0
0.0
blood
lung liver(all) spleen kidney muscle heart
brain
bone
tumor
Organ
Tumor uptake of complex 1 is significantly
higher than that for
[64Cu((EtOCH2CH2)2PCH2CH2P(CH2CH2EtO)2)]+
Biodistribution was carried out on 16-18 g female BALB/c mice implanted with
EMT-6 cells subcutaneously into the left flank. Tumors were allowed to grow
for 14 days (approx 0.3 – 0.7 cm3), at which time the animals received 0.20
MBq (~5 μCi) of complex 1 in 100 μL of saline via lateral tail vein injection.
Mice were examined at 3 time points (n = 4 per group at 1, 4 and 24 hours).
S. Alidori, G. Gioia Lobbia, G. Papini, M. Pellei, M. Porchia, F. Refosco, F. Tisato, J.S. Lewis, C. Santini
Journal of Biological Inorganic Chemistry, 13 (2008) 307-315.
1h
2h
Small animal
24 h
PET Imaging
axial
Scale
Off-Scale
High
coronal
Low
Selected axial and coronal
images obtained using coregistration techniques
demonstrating the uptake of 1
at 1, 2 and 24 h post injection
in a mouse with an EMT-6
tumor (arrow) implanted on
the flank.The EMT-6 tumors
can be easily visualized at all
time points
5
Standard uptake values (SUVs) of 1 in
selected organs in EMT-6 tumor bearing
mice over 24 h (n = 4).
Tumor
Muscle
Liver
4
Kidney
Heart
SUV
3
The uptake in the EMT-6 tumor at 1 h which
remained static over 24 h
2
1
0
0
5
10
15
Time (h)
20
25
New N-, P- donor ligands
O
H3C
O
O
O
P
O
N
N
H3C
O
P
O
O
O
O
P
CH3
O
O
P
P
O
O
O
O
N
N
O
N
N
P
O
CH3
O
O
O
O
P
O
H3C
P
P
O
H3C
O
Cyclen
H2N
H3C
O
O
O
P
O
O
O
P
CH3
H3C
Br
O
O
P
O
P
Br
O
O
O
O
P
P
O
N
N
N
N
O
N
H
CH3
O
O
Cyclam
NH2
O
O
P
O
O
O
CH3
N
H
CH3
CH3
H3C
O
O
P
O
P
H3C
O
O
O
O
CH3
H3C
O
O
CH3
O
P
H3C
O
O
H2P
P
O
N
N
PH2
CH3
LiAlH4
N
O
O
P
P
H3C
O
N
N
N
N
CH3
H3C
N
O
O
H2P
CH3
PH2
O
1. n-BuLi
1. HCHO, HCl, EtOH
2. NaHCO3
HO
2. RX
OH
HO
P
OH
P
HO
N
N
N
N
R
R
R
P
P
N
N
N
N
R
P
HO
OH
P
R
P
OH
R
P
R
R
New macrociclic ligands
G. Papini, S. Alidori, J. S. Lewis, D. E. Reichert M. Pellei,, G. Gioia Lobbia, G. B. Biddlecombe, C. J. Anderson,
C. Santini J. Med. Chem. (2008) submitted
HOOC
COOH
NH
HN
+
SH
HS
Br
Br
1) NaHCO3
HOOC
H
N+
H
H
N+
H
COOH
(CH2)2
2) HCl, pH = 2
S
S
12-membered NEC-SE
HOOC
COOH
NH
HOOC
HN
+
SH
HS
Br
Br
H
N+
H
H
1) NaHCO3
N+
H
COOH
(CH2)3
2) HCl, pH = 2
S
S
13-membered NEC-SP
HOOC
COOH
NH
HOOC
HN
+
SH
HS
Br
Br
H
N+
H
H
1) MeOH/H2O/NaOH
N+
H
COOH
(CH2)4
2) HCl, pH = 2
S
S
14-membered NEC-SB
HOOC
NH2
SH
HCHO
H 2O
HOOC
H
N
S
1) Na/NH3
2) NH4Cl, pH = 2
HOOC
NH HN
SH HS
P. Blondeau, C. Berse, D. Gravel, Can. J. Chem. 45 (1967) 49.
COOH
Copper(II) complexes
HOOC
H
N+
H
H
N+
H
COOH
H2O
S
NH
Cu(CH3COO)2
O
H
N+
S
N+
H
NH
COOH
Cu(CH3COO)2
O
HOOC
H
S
NH
H
N+
H
COOH
S
14-membered NEC-SB
S
NH
Cu O
O
S
Cu(NEC-SP)
13-membered NEC-SP
H
N+
O
S
H2O
S
O
Cu(NEC-SE)
H
H
Cu O
S
S
12-membered NEC-SE
HOOC
O
NH
Cu(CH3COO)2
H2O
O
O
S
NH
Cu O
O
S
Cu(NEC-SB)
G. Papini, S. Alidori, J. S. Lewis, D. E. Reichert, M. Pellei, G. Gioia Lobbia, G. B. Biddlecombe, C. J. Anderson, C.
Santini J. Med. Chem. (2008) submitted
64Cu
HOOC
H
N+
H
S
NH
H
N+
H
64
COOH
Cu(II)Cl2
64
Macrociclic ligands
Cu O
S
Sodium acetate
buffer
S
NH
64
O
O
O
S
Cu-Complexes
Biodistribution data
12
The retention of activity in tissues is
similar to that observed with 64Cu-cyclam
and 64Cu-monooxo-tetrazamacrocyclic
complexes, but, on comparison with
64Cu-TETA and 64Cu-DOTA, the uptake
and retention of and are orders-of-
10
magnitude higher.
18
Blood
16
Liver
Kidney
14
%ID/organ
complexes
8
The poor clearance suggests that the
complexes are rapidly degraded in
blood and tissues and the 64Cu is
sequestered by proteins, and
remaining trapped in these tissues
hindering clearance.
6
4
2
0
7
8
9
Cu-64-Cyclam
Complex
Cu-64-TETA
Cu-64-DOTA
Cu-CB-TE2A
Perspectives
Cl
Cl
HOOC
NH HN
COOH
NH HN
HOOC
X
S
SH HS
COOH
S
X
HOOC
NH HN
S
ROH, HCl
COOH
SO3O
S
S
COOH
O
1)
NaOH, pH = 5.5
2)
sulfo-NHS, EDC
O
HO
H
N
O
O
NH HN
S
HO
O
O
S
1)
pH = 7.5
2)
BM-NH2 . HCl
COOR
S
H O
O
N
NH HN
NH HN
S
S
SO3-
HOOC
ROOC
H
H
H
HN
NH
H
HO
O
OH
HO
NH HN
S
H
HN
NH
H
HO
OH
O
OH
H
O H
H O
H
BFCA
H
O
S
H
M
OH
OH
H
CuAc
H2 O
HO
H
HO
OH
H
O H
H
HO
N
N
Cu
S
S
O
OH
H
OH
Conclusions
The monooxo Re(V) core is conveniently stabilized by tripodal scorpionate ligands
comprising carboxylate or sulfonate tails, giving a series of intermediate
Re(O)(NNO)Cl(X) (X = Cl, OR). To these entities various bidentate ligands (BID) can be
attached to produce "3 + 2" mixed ligand compounds.
Hydrophilic ‘cold’ Cu(I)-complexes have shown significant antiproliferative activity in
vitro on a series of tumor cell lines, also resistance to cisplatin, showing a different
pathway of action from that of cisplatin.
Hydrophylic ‘hot’ 64Cu(I) monophosphine complexes were evaluated as a basis for a
new class of copper radiopharmaceuticals. [64Cu(thp)4]+ = building-block for new
radiopharmaceuticals, perhaps the first time such a method has been used in the
production of Cu-radiopharmaceuticals.

Novel macrocyclic ligands, based on the L,L-ethylenedicysteine skeleton, have been
prepared in view of the attractive opportunity to use them as bifunctional chelators for
copper nuclides. This is the first report of 64Cu labeled to this form (N2S2)
macrocyclics. Although the in vivo biodistribution of complexes suggests dissociation
of the 64Cu from the chelates, these new ligands platform offers the potential as a basis
for further development to improve the in vivo stability.
Partners and Acknowledgements
Prof. Giancarlo Gioia Lobbia
Prof. Carlo Santini
Dr.ssa Maura Pellei
Dr. Simone Alidori
Prof. Giuliano Bandoli
Prof. Alessandro Dolmella
Dr.ssa Cristina Marzano
Dip. di Scienze Farmaceutiche
Università di Padova
Prof. Jason S. Lewis
Carolyn J. Anderson
Dr. Franco Benetollo
ICIS-CNR, Padova
Dr. Francesco Tisato
Dr.ssa Marina Porchia
Dr. Fiorenzo Refosco,
Dr.ssa Cristina Bolzati
ICIS-CNR, Padova
Prof. Rasika Dias
Department of Chemistry and Biochemistry
The University of Texas at Arlington (USA)