New rhenium complexes with ciprofloxacin as useful models for understanding the properties of [99mTc]-ciprofloxacin radiopharmaceutical.
Rhenium complexes with the antibiotic ciprofloxacin have been prepared to be studied as models of technetium radiopharmaceuticals. With this aim, the new rhenium complexes 1 {[ReO(Cpf)2]Cl}, 2 {[ReO(CpfH)2]Cl3} and 3 {fac-[Re(CO)3(H2O)(Cpf)]} with ciprofloxacin (CpfH=ciprofloxacin; Cpf=conjugated base of ciprofloxacin) have been synthesised and characterised by elemental analyses, IR, NMR ((1)H, (19)F and (13)C CP-MAS) spectroscopy, as well as MS measurements. All spectroscopic data are consistent with the coordination of ciprofloxacin in all these complexes through the carbonyl and the carboxylate oxygen atoms with the formation of a six member chelate ring. The study of a Tc-ciprofloxacin solution by ESI-MS reveals the presence of [TcO(Cpf)2](+) cations, which agrees with the hypothesis that complexes 1 and 2 can be seen as model rhenium complexes of this radiopharmaceutical. Antimicrobial and DNA gyrase inhibition studies performed with complexes 2 and 3 have shown a very similar behaviour between complex 2 and the free antibiotic, whereas complex 3 exhibit a lower antimicrobial activity. Based on a joint analysis of the data reported in the literature and the chemical and biological results obtained in this study, a tentative proposal to explain some aspects of the behaviour of Tc-ciprofloxacin radiopharmaceutical has been made.
Departament de Química, Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
Joan
J
Lecina
Grup de Microbiologia Molecular, Department de Genètica i de Microbiologia, Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
Pilar
P
Cortés
Grup de Microbiologia Molecular, Department de Genètica i de Microbiologia, Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
Montserrat
M
Llagostera
Unitat de radiofarmacia, Servei de Medicina Nuclear (CDIC), Hospital Clínic de Barcelona, Villaroel 170, 08036 Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer, Villaroel 170, 08036 Barcelona, Spain.
Carlos
C
Piera
Departament de Química, Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain. Electronic address: Joan.Suades@uab.es.
Joan
J
Suades
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000031:analogs & derivatives / Q000737:chemistry*; D027081:DNA Gyrase / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D013293:Enterococcus faecalis / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D012211:Rhenium / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects; D013329:Structure-Activity Relationship; D059005:Topoisomerase II Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; D059005:Topoisomerase II Inhibitors; D002939:Ciprofloxacin; D012211:Rhenium; D027081:DNA Gyrase
Ciprofloxacin; Infection; Metal carbonyl; Radiopharmaceutical; Rhenium; Technetium