204068-47-3

Upstream product

• 155337-52-3 RTI 83 
• 22873-28-5 p-ethylphenylmagnesium bromide 
• 50373-10-9 methyl ecgonidine 

Downstream Products

• 1026290-19-6 (1R,2S,3S,5S)-3-(4-Ethyl-3-iodo-phenyl)-8-aza-bicyclo[3.2.1]octane-2,8-dicarboxylic acid 2-methyl ester 8-(2,2,2-trichloro-ethyl) ester 
• 198990-83-9 2β-carbomethoxy-3β-(4'-ethyl-3'-iodophenyl)nortropane 

Relevant academic research and scientific papers

Synthesis of tropane and nortropane analogues with phenyl substitutions as serotonin transporter ligands

The effects of structural modifications of β-carboxymethoxy-3β-phenyl tropane analogues were evaluated on in vitro affinity to the dopamine (DAT) and serotonin (5-HTT) transporters in rat brain tissue. The introduction of a large alkyl group at the 4′-position of the phenyl ring, affording 2β-carbomethoxy-3β-(4′-alkylphenyl) tropane, diminished the affinity for the DAT whereas moderate 5-HTT affinity was obtained. The introduction of an iodine at the 3′-position of the 4′-alkylphenyl, affording 2β-carbomethoxy-3β-(3′-iodo-4′-alkylphenyl) tropane, and N-demethylation, affording 2β-carbomethoxy-3β-(3′-iodo-4′-alkylphenyl) nortropane, improved affinity and specificity for the 5-HTT. It could be assumed from these results that the combination of these three modifications of tropane structure yielded highly selective compounds for the 5-HTT. Of the new compounds synthesized, the most selective cocaine derivative, 2β-carbomethoxy-3β-(3′-iodo-4′-isopropylphenyl) nortropane (8d) labeled with iodine-123 or carbon-11, could be a potential ligand for exploration of the 5-HT transporter by SPET or PET. Copyright

Synthesis of [11C]2β-Carbomethoxy-3β-(3'-iodo-4'-methyl, -ethyl and isopropyl Phenyl)Nortropane as Potential Radiotracers for Examination of the Serotonin Transporter with Positron Emission Tomography

Research on depression and anxiety disorders would benefit from the development of suitable radioligands for PET-imaging of the serotonin transporter. Three cocaine analogues, 2β-carbomethoxy-3β-(3'-iodo-4'-methyl, -ethyl and isopropyl phenyl)nortropane (LBT-14, EINT and LBT-44), were prepared in a three-step synthesis by 1-4 addition of the appropriate Grignard reagent to anhydroecgonine methyl ester as first step. lodination of the phenyl ring was accomplished with a mixture of yellow mercuric oxide, perchloric acid and acetic acid followed by a solution of iodine in dichloromethane. N-desmethylation was performed by using 2,2,2-trichloroethylchloroformiate followed by treatment of zinc in acetic acid. Acidic hydrolysis of the ester functions gave the carboxylic acid analogues of LBT-14, EINT and LBT-44. The precursors were labelled with 11C using [11C]methyl iodide or [11C]methyl triflate in dimethyl formamide (DMF) and tetrabutyl ammonium hydroxide (TBAH) as base. [11C]LBT-14, [11C]EINT and [11C]LBT-44 were all examined in Cynomolgus monkey with PET. All three compounds entered the monkey brain to a high degree (ca. 5-10 percent of injected dose). There was a marked uptake of radioactivity in the thalamus and the brainstem, regions known to contain serotonin transporters. Pre-treatment with the selective serotonin transporter inhibitor citalopram had minor effect on the binding ratios, suggesting that none of the three examined radioligands are preferable to the previously examined non-iodinated 4'-isopropenyl analogue [11C]RTI-357 for the study of the serotonin reuptake system with PET.