Synthesis and Biological Evaluation of [Carboxyl-11C]eprosartan
2009 (English)In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 52, no 8, 295-303 p.Article in journal (Refereed) Published
Essential hypertension occurs in approximately 25% of the adult population and one cause of hypertension is primary aldosteronism. Targeting the angiotensin II AT1 receptor using PET and an appropriate tracer may offer a diagnostic method for adrenocortical tissue. This report describes the synthesis of the selective AT1 receptor antagonist [carboxyl-11C]eprosartan 10, 4-[2-butyl-5-((E)-2-carboxy-3-thiophen-2-yl-propenyl)-imidazol-1-ylmethyl]-[carboxyl-11C]benzoic acid, and its precursor (E)-3-[2-butyl-3-(4-iodo-benzyl)-3H-imidazol-4-yl]-2-thiophen-2-ylmethyl-acrylic acid 9. 11C-carboxylation of the iodobenzyl moiety was performed using a palladium-mediated reaction with [11C]carbon monoxide in the presence of tetra-n-butyl-ammonium hydroxide in a micro-autoclave using a temperature gradient from 25 to 140°C over 5 min. After purification by semipreparative HPLC, [carboxyl-11C]eprosartan 10 was obtained in 37–54% decay-corrected radiochemical yield (from [11C]carbon monoxide) with a radiochemical purity >95% within 35 min of the end of bombardment (EOB). A 5-µAh bombardment gave 2.04 GBq of 10 (50% rcy from [11C]carbon monoxide) with a specific activity of 160 GBq µmol−1 at 34 min after EOB. Frozen-section autoradiography shows specific binding in kidney, lung and adrenal cortex. In vivo experiments in rats demonstrate a high accumulation in kidney, liver and intestinal wall.
Place, publisher, year, edition, pages
2009. Vol. 52, no 8, 295-303 p.
angiotensin II, AT1, eprosartan, [11C]carbon monoxide, carboxylation, isotopic labelling, 11C, PET
Research subject Organic Pharmaceutical Chemistry; Organic Chemistry
IdentifiersURN: urn:nbn:se:uu:diva-98594DOI: 10.1002/jlcr.1598ISI: 000268690300032OAI: oai:DiVA.org:uu-98594DiVA: diva2:175156