Radiosynthesis of a potent muscarinic cholinergic receptor ligand, p-iododexetimide, via p-iodobenzyl bromide: A new reagent for the introduction of radioactive iodine into biologically interesting molecules

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:5973902

Wilson, A A; Dannals, R F; Ravert, H T; Frost, J J; Burns, H D; Wagner, Jr, H N

Radioiodinated p-iodobenzyl bromide is a potentially useful alkylating agent for the introduction of radioactive iodine into biologically interesting molecules. I-125 and I-123 labeled are prepared for the first time at the no carrier added level by an electrophilic substitution reaction on p-trimethylsilylbenzyl bromide using N-chlorosuccinimide in acetic acid. After HPLC purification, isolated yields of 70-80% were obtained within 1 hour with specific activities of 600-1500 mCi/..mu..mole. The utility of radioiodinated is demonstrated by the synthesis of radioiodinated p-iododexetimide, a potent muscarinic receptor antagonist (Kd=2.7 nM). Labeled with I-125 or I-123 was reacted with norbenzyldexetimide in 55% aqueous acetonitrile at 60 deg C for 10 mins to give, after HPLC purification, a 70-80% yield of I-125 or I-123 p-iododexetimide (>99% radiochemically pure). Specific activities of above 600 mCi/..mu..mole were obtained in 65 mins from production of radioiodinated. Currently, the authors are evaluating radioiodinated p-iododexetimide as a muscarinic cholinergic receptor imaging agent for use with single photn emission computed tomography.

• Research Organization: The Johns Hopkins Medical Institutions, Baltimore, MD
• OSTI ID: 5973902
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
550602 -- Medicine-- External Radiation in Diagnostics-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
ALKYLATING AGENTS
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
CARBOXYLIC ACIDS
CHEMICAL PREPARATION
COMPUTERIZED TOMOGRAPHY
DAYS LIVING RADIOISOTOPES
DIAGNOSTIC TECHNIQUES
DIAGNOSTIC USES
DICARBOXYLIC ACIDS
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
EMISSION COMPUTED TOMOGRAPHY
HOURS LIVING RADIOISOTOPES
IMIDES
INTERMEDIATE MASS NUCLEI
IODINE 123
IODINE 125
IODINE ISOTOPES
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LABELLING
LIGANDS
MEMBRANE PROTEINS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PROTEINS
RADIOISOTOPES
RADIOPHARMACEUTICALS
REACTION KINETICS
RECEPTORS
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY
SYNTHESIS
TOMOGRAPHY
USES