Journal of Labelled Compounds and Radiopharmaceuticals

Coumbarides, Gregory S.; Eames, Jason; Weerasooriya, Neluka

doi: 10.1002/jlcr.613pmid: N/A

A series of multi‐labelled (D, 13C) 2,2‐dimethyl tetralones were efficiently synthesized using a simple and diverse deprotonation–methylation strategy. All possible ten isotopic combinations were synthesized. The levels of (D, 13C) isotopic incorporation were quantitative and the synthetic yields were high. Copyright © 2002 John Wiley & Sons, Ltd.

Beiki, Davood; Shahhosseini, Soraya; Khalaj, Ali; Eftekhari, Mohammad

doi: 10.1002/jlcr.608pmid: N/A

Human nonspecific polyclonal IgG was labelled with 125I through direct and indirect labelling methods using chloramine‐T and a nonphenolic radioiodinated intermediate N‐succinimidyl‐4‐(125I)iodobenzoate (125I‐SIB), respectively. Tissue distribution of radioiodinated IgG was assessed in normal and induced inflammation mice. Although, radioiodinated IgG accumulated in the inflammatory area, results showed decreased thyroid and stomach activity and improved inflammatory thigh‐to‐normal tissue ratios with the indirect labelling method (125I‐IB‐IgG) compared with the direct labelling method (125I‐IgG), indicating reduced in vivo deiodination. These results indicate that the 125I‐SIB is probably a preferable approach for labelling antibodies with iodine radioisotopes. Copyright © 2002 John Wiley & Sons, Ltd.

Coumbarides, Gregory S.; Eames, Jason; Weerasooriya, Neluka

doi: 10.1002/jlcr.603pmid: N/A

Results are reported on the synthesis and characterization of a variety of trideuteriomethyl aryl ketones. Copyright © 2002 John Wiley & Sons, Ltd.

Mourot, A.; Kotzyba‐Hibert, F.; Doris, E.; Goeldner, M.

doi: 10.1002/jlcr.614pmid: N/A

A new synthesis of a tritiated photosensitive nicotinic agonist ((3H)–AC5), which uses (3H2) as the source of radioactivity, is described. Several improvements have been introduced to establish a reliable five‐step synthesis displaying satisfactory overall yields (45%) and requiring a single purification (HPLC) in the final step. This photosensitive radiolabelled probe will enable us to undertake a time‐resolved photolabelling study on the nicotinic acetylcholine receptor in order to analyze at the molecular level the allosteric transitions occurring after agonist stimulation. Copyright © 2002 John Wiley & Sons, Ltd.

Waterhouse, Rikki N.; Dumont, Filip; Sultana, Abida; Simpson, Norman; Laruelle, Marc

doi: 10.1002/jlcr.622pmid: N/A

The N‐methyl‐D‐aspartate (NMDA) ion channel plays an important role in a number of neurodegenerative disorders including stroke, Parkinson's disease, Huntington's Chorea, Alzheimer's disease, schizophrenia and epilepsy. To provide effective radioligands for imaging the PCP binding site of the NMDA ion channel, we synthesized and characterized in vitro the candidate PCP site ligand N‐(2‐chloro‐5‐thiomethylphenyl)‐N′‐(3‐methoxyphenyl)‐N′‐methylguanidine (GMOM: Ki = 5.2 ± 0.3 nM, log P = 2.34). The corresponding PET radiotracer (11C)GMOM was synthesized with a radiochemical yield of 8.4 ± 3.2% EOS and with a specific activity of 1.23 ± 0.25 Ci/μmol EOS (n = 5). The average time required for synthesis, purification and formulation was 52 ± 5 min. The final product was prepared in a sterile saline solution suitable for in vivo use. Copyright © 2002 John Wiley & Sons, Ltd.

Coumbarides, Gregory S.; Eames, Jason; Weerasooriya, Neluka

doi: 10.1002/jlcr.615pmid: N/A

Results are reported on the regioselective C‐deuteriation of 2‐methyl tetralone using a series of diisopropylamine derived D‐sources. The results presented further aid the understanding of kinetic deuteriation of both ‘base‐containing’ and ‘base‐free’ enolates. Copyright © 2002 John Wiley & Sons, Ltd.

Furumoto, Shozo; Iwata, Ren; Ido, Tatsuo

doi: 10.1002/jlcr.616pmid: N/A

Matrix metalloproteinases (MMPs) are key enzymes involved in cancer invasion and metastasis. New 18F‐labeled MMP inhibitors (1a–c) has been designed and synthesized for cancer imaging by positron emmision tomography. The precursors were synthesized in four steps starting from D‐form of amino acids. Radiosynthesis of 1a–c were carried out by simple one‐pot synthesis. The resulting radiofluorinated MMP inhibitors were obtained in overall radiochemical yields of 13–43% (EOB, decay corrected) within 60–70 min (including final preparative HPLC separation). Copyright © 2002 John Wiley & Sons, Ltd.

Dischino, Douglas D.; Mattson, Ronald J.; Ogan, Marc D.; Parker, Michael F.; Yevich, Joseph P.

doi: 10.1002/jlcr.618pmid: N/A

The synthesis of two 125I‐labeled trisubstituted aromatic melatonergic agents is reported. N‐((2‐(125I)iodo‐5‐methoxyphenyl)‐1R, 2R‐cyclopropyl)methyl) butanamide was prepared from the corresponding thallium salt and Na 125I in radiochemical yields of 13–45% (n = 3). High performance liquid chromatography separation of the two resulting radioiodinated isomers (8:2) from each other and the parent compound required the use of two different columns run in series. Synthesis of N‐((2‐(125I)iodo‐5‐fluorophenyl)‐1R, 2R‐cyclopropyl)methyl) butanamide was prepared from the corresponding trimethylstannane precursor in radiochemical yields consistently in the range of 60–65% (n = 6). Copyright © 2002 John Wiley & Sons, Ltd.