Radiosynthesis and Bioimaging of the Tuberculosis Chemotherapeutics Isoniazid, Rifampicin and Pyrazinamide in Baboons
摘要:
The front-line tuberculosis (TB) chemotherapeutics isoniazid (INH), rifampicin (RIF), and pyrazinamide (PZA) have been labeled with carbon-11 and the biodistribution of each labeled drug has been determined in baboons using positron emission tomography (PET). Each radiosynthesis and formulation has been accomplished in 1 h, using [C-11]CH3I to label RIF and [C-11]HCN to label INH and PZA. Following iv administration, INH, PZA, RIF, and/or their radiolabeled metabolites clear rapidly from many tissues; however, INH, PZA, and/or their radiolabeled metabolites accumulate in the bladder while RIF and/or its radiolabeled metabolites accumulates in the liver and gall bladder, consistent with the known routes of excretion of the drugs. In addition, the biodistribution data demonstrate that the ability of the three drugs and their radiolabeled metabolites to cross the blood brain barrier decreases in the order PZA > INH > RIF, although in all cases the estimated drug concentrations are greater than the minimum inhibitory concentration (MIC) values for inhibiting bacterial growth of Mycobacterium tuberculosis (MTB). The pharmacokinetic (PK) and drug distribution data have important implications for treatment of disseminated TB in the brain and pave the way for imaging the distribution of the pathogen in vivo.
Radiosynthesis and Bioimaging of the Tuberculosis Chemotherapeutics Isoniazid, Rifampicin and Pyrazinamide in Baboons
摘要:
The front-line tuberculosis (TB) chemotherapeutics isoniazid (INH), rifampicin (RIF), and pyrazinamide (PZA) have been labeled with carbon-11 and the biodistribution of each labeled drug has been determined in baboons using positron emission tomography (PET). Each radiosynthesis and formulation has been accomplished in 1 h, using [C-11]CH3I to label RIF and [C-11]HCN to label INH and PZA. Following iv administration, INH, PZA, RIF, and/or their radiolabeled metabolites clear rapidly from many tissues; however, INH, PZA, and/or their radiolabeled metabolites accumulate in the bladder while RIF and/or its radiolabeled metabolites accumulates in the liver and gall bladder, consistent with the known routes of excretion of the drugs. In addition, the biodistribution data demonstrate that the ability of the three drugs and their radiolabeled metabolites to cross the blood brain barrier decreases in the order PZA > INH > RIF, although in all cases the estimated drug concentrations are greater than the minimum inhibitory concentration (MIC) values for inhibiting bacterial growth of Mycobacterium tuberculosis (MTB). The pharmacokinetic (PK) and drug distribution data have important implications for treatment of disseminated TB in the brain and pave the way for imaging the distribution of the pathogen in vivo.
Copper(II)-Mediated [<sup>11</sup>C]Cyanation of Arylboronic Acids and Arylstannanes
作者:Katarina J. Makaravage、Xia Shao、Allen F. Brooks、Lingyun Yang、Melanie S. Sanford、Peter J. H. Scott
DOI:10.1021/acs.orglett.8b00242
日期:2018.3.16
A copper-mediated method for the transformation of diverse arylboron compounds and arylstannanes to aryl-[11C]-nitriles is reported. This method is operationally simple, uses commercially available reagents, and is compatible with a wide variety of substituted aryl- and heteroaryl substrates. This method is applied to the automated synthesis of high specific activity [11C]perampanel in 10% nondecay-corrected
Copper-Mediated Radiocyanation of Unprotected Amino Acids and Peptides
作者:Liam S. Sharninghausen、Sean Preshlock、Stephen T. Joy、Mami Horikawa、Xia Shao、Wade P. Winton、Jenelle Stauff、Tanpreet Kaur、Robert A. Koeppe、Anna K. Mapp、Peter J. H. Scott、Melanie S. Sanford
DOI:10.1021/jacs.2c01959
日期:2022.4.27
functional groups, including unprotected aminoacids. As such, it enables the site-specific introduction of [11C]CN into peptides at an iodophenylalanine residue. The use of a diamine-ligated copper(I) mediator is crucial for achieving high radiochemical yield under relatively mild conditions, thus limiting racemization and competing side reactions of other aminoacid side chains. The reaction has been scaled
A highly efficient method applicable to the synthesis of a wide range of [11C]cyanoarenes, including PET tracers for aromatase imaging, has been developed by a palladium(ii)-mediated rapid 11C-cyanation of (hetero)arylborons with [11C]cyanides.
CuI-mediated 11C-cyanation was evaluated by synthesizing [11C]perampanel ([11C]5) as a model compound and compared with previous reports. To a DMF solution with 5′-(2-bromophenyl)-1′-phenyl-[2,3′-bipyridin]-6′(1′H)-one (4) and CuI, [11C]NH4CN in a stream of ammonia/nitrogen (5:95, v/v) gas was bubbled. Subsequently, the reaction mixture was heated at 180°C for 5 min. After HPLC purification, [11C]5 was obtained in 7.2 ± 1.0% (n = 4) non-decay corrected radiochemical yield with >99% radiochemical purity and a molar activity of 98 ± 28 GBq/μmol. In vivo evaluations of [11C]5 were performed using small animals. PET scans to check the kinetics of [11C]5 in the whole body of mice suggested that [11C]5 spreads rapidly into the brain, heart, and lungs and then accumulates in the small intestine. To evaluate the performance of CuI-mediated 11C-cyanation reaction, bromobenzene (6a) was selected as the model compound; however, it failed. Therefore, optimization of the reaction conditions has been performed, and consequently, the addition of K2CO3 and prolonging the reaction time improved the radiochemical yield about double. With this improved method, CuI-mediated 11C-cyanation of various (hetero)aromatic bromides was performed to exhibit the tolerance of most functional groups and to provide 11C-cyanated products in good to moderate radiochemical yields.
Radiosynthesis and Bioimaging of the Tuberculosis Chemotherapeutics Isoniazid, Rifampicin and Pyrazinamide in Baboons
作者:Li Liu、Youwen Xu、Colleen Shea、Joanna S. Fowler、Jacob M. Hooker、Peter J. Tonge
DOI:10.1021/jm901858n
日期:2010.4.8
The front-line tuberculosis (TB) chemotherapeutics isoniazid (INH), rifampicin (RIF), and pyrazinamide (PZA) have been labeled with carbon-11 and the biodistribution of each labeled drug has been determined in baboons using positron emission tomography (PET). Each radiosynthesis and formulation has been accomplished in 1 h, using [C-11]CH3I to label RIF and [C-11]HCN to label INH and PZA. Following iv administration, INH, PZA, RIF, and/or their radiolabeled metabolites clear rapidly from many tissues; however, INH, PZA, and/or their radiolabeled metabolites accumulate in the bladder while RIF and/or its radiolabeled metabolites accumulates in the liver and gall bladder, consistent with the known routes of excretion of the drugs. In addition, the biodistribution data demonstrate that the ability of the three drugs and their radiolabeled metabolites to cross the blood brain barrier decreases in the order PZA > INH > RIF, although in all cases the estimated drug concentrations are greater than the minimum inhibitory concentration (MIC) values for inhibiting bacterial growth of Mycobacterium tuberculosis (MTB). The pharmacokinetic (PK) and drug distribution data have important implications for treatment of disseminated TB in the brain and pave the way for imaging the distribution of the pathogen in vivo.