326 R. BISCHOFF ET AL.
Br
I
I
i. Boc2O, NEt3
cat. DMAP,
75%
TFA
57%
O
O
O
ii. NaI, CuI, 120 oC
NH2(CH2)3NH2
O
O
O
OEt
OEt
OEt
N
H
N
H
N
49%
Boc
25
26
Scheme 5
labelled N,N-bis(tert-butoxycarbonyl)-1H-pyrazole-1-
carboxamidine would allow the selective incorporation
of stable isotopes at a late stage of this synthesis of
blastidic acid.
first synthesis of an (S,R)-diastereomer of reboxetine
which after binding studies will be radioiodinated for
SPECT imaging.
Acknowledgement
Financial support from the University of Glasgow,
EPSRC and SHERT is gratefully acknowledged.
More recently our research programme for the
synthesis of isotopically labelled, biologically active
compounds has focused on identifying a new imaging
tracer for the NAT. Our aim has been to synthesize
radioiodinated analogues of reboxetine, a known in-
hibitor of NAT which could be used for SPECT imaging.
The synthesis of an iodinated (S,R)-diastereomer of
reboxetine has been completed using a Wadsworth–
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Copyright # 2007 John Wiley & Sons, Ltd.
J Label Compd Radiopharm 2007; 50: 323–326
DOI: 10.1002.jlcr