Radioiodination of 4-benzyl-1-(3-iodobenzylsulfonyl)piperidine, 4-(3-iodobenzyl)-1-(benzylsulfonyl)piperazine and their derivatives via isotopic and non-isotopic exchange reactions

Abstract

A mild and simple technique for preparing of 4-benzyl-1-(3-[ 125 I]iodobenzylsulfonyl)piperidine, 4-(3-[ 125 I] iodobenzyl)-1-(benzylsulfonyl)piperazine and their derivatives, as sigma-1 receptor ligands, with relatively high radiochemical yields via nucleophilic substitution reaction by means of isotopic and non-isotopic exchange reactions is described. Some factors affecting the radiochemical yield were commonly studied in presence of acidic medium at elevated temperature. Unfortunately, the radiochemical yields were weak. Some attempts were carried out in presence of polar aprotic solvents to enhance the radiochemical yield. N,NDimethylformamide was proved highly efficient for preparing of radioiodinated 4-benzyl-1-(3-iodobenzylsulfonyl)piperidine (4-B-[ 125 I]-IBSP, 70 ± 5.7 %) and 4-(3-iodobenzyl)-1-(benzylsulfonyl)piperazine (4-[ 125 I]-IBBSPz, 72 ± 6.0 %) at moderate temperature (100-105°C) within 8 h. The specific activities of 4-B-[ 125 I]-IBSP and 4-[ 125 I]-IBBSPz (6,534.2 and 5,927.4 MBq/mmol) were obtained respectively.Keywords Radioiodination Á Isotopic and non-isotopic exchange Á 125 I Á 4-Benzyl-1-(3-iodobenzylsulfonyl) piperidine Á 4-(3-Iodobenzyl)-1-(benzylsulfonyl) piperazine Á Sigma-1 receptor ligands

Assessment of the effective absorbed dose of 4-benzyl-1-(3-[125I]-iodobenzylsulfonyl)piperidine in humans on the basis of biodistribution data of rats

“…Based on these findings the authors were interested in radiolabelling the best ligand with high binding affinity and relatively good selectivity, 4-B-IBSP, with iodine-125 ( 125 I) ( Fig. 1) in order to investigate the uptake values of radiolabeled sigma ligands in target organs [17]. On the basis of the promising results of the biodistribution data of 4-benzyl-1-(3-[ 125 I]-iodobenzylsulfonyl)piperidine (4-B-[ 125 I]-IBSP) obtained from normal rats, it was concluded that this tracer may be used as an imaging agent for early detection of various cancers such as breast, prostate, liver, and lung cancers, although internal dosimetry calculations are still needed.…”

Development of Small HN Linked Radionuclide Iodine-125 for Nanocarrier Image Tracing in Mouse Model

“… 32 The binding principle of radionuclides to HN is that hydrogen ions near phenolic hydroxyl group of HN were replaced with the radionuclide via the nucleophilic substitution reaction. 33 Thus, the linker HN consists of a phenolic hydroxyl group and a carboxylate group to bind to radionuclides and primary NC amines, respectively. Based on the above design, two reactants were used to synthesize linker HN.…”

“…125 I-NCs were prepared using a diimide-activated amidation reaction. 33 Briefly, 5 mg of EDC and 10 mg of NHS were added into 200 μL of NCs (5.0 mg/mL) diluted with 800 μL of DI water. The mixture was stirred for 2 h at room temperature.…”

“…The NCs (CeO 2 , La 2 O 3 , SiO 2 ) without the hydroxyl, carboxyl, or amino groups on their surface were first functionalized with APTES by dispersing the NCs in ethanol that contained 5% APTES and heating at 60°C for 3 h. 2) Investigation of 125 I-NC Synthesis and Stability 125 I-NCs were prepared using a diimide-activated amidation reaction. 33 Briefly, 5 mg of EDC and 10 mg of NHS were added into 200 μL of NCs (5.0 mg/mL) diluted with 800 μL of DI water. The mixture was stirred for 2 h at room temperature.…”