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Nuclear medicine technology. Progress report for quarter ending September 30, 1979

Description: Adrenal uptake in rats of /sup 117m/Sn-labeled 23-(trimethyl stanna)-24-nor-5..cap alpha..-cholan-3..beta..-o1 is demonstrated. The adrenal:blood and adrenal:liver ratios were 33:1 and 9:1, only one day after intravenous administration. A variety of /sup 117m/Sn-labeled steroids with structural modifications were also prepared to determine their effects on the adrenal uptake of these unusual steroids. Structural features required for significant adrenal uptake were determined. The diffusion chamber assay system has been assessed as a means of investigating the toxicity and biological fate of trace elements from energy technologies. In a preliminary experiment, the cell population in chambers from rats exposed to As/sub 2/O/sub 3/ was inhibited 48% one day after treatment. The results of continuing studies with /sup 75/Se, /sup 11/C, and /sup 195m/Pt-labeled agents are also described. Several /sup 75/Se-labeled long-chain fatty acids were prepared to determine heart uptake. Selenium-75-labeled 9-selenapentacosanoic acid showed the highest uptake of the compounds investigated. Preliminary radiation dose estimates have been performed for several /sup 75/Se and /sup 123m/Te-labeled fatty acids. Tissue distribution and excretion data for /sup 75/Se-labeled 9-selenaheptadecanoic acid and /sup 123m/Te-labeled 9-telluraheptadecanoic acid indicate that the human liver would recieve the highest absorbed radiation dose.Tissue distribution studies in rats with a series of /sup 195m/Pt-labeled chloroammine complexes have demonstrated that the tissue distribution and excretion characteristics of the chlorcammine complexes closely parallel their physicochemical properties. Further patient studies have assessed the efficacy of emission computerized tomographic organ imaging with /sup 11/C-valine, and /sup 11/C-amino-cyclobutanecarboxylic acid (ACBC). (ERB)
Date: January 1, 1979
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Nuclear medicine technology progress report for quarter ending June 30, 1979

Description: Diffusion chamber assay system studies on the relative cytotoxicity and target cell uptake of /sup 195m/Pt-labeled cis- and trans-dichlorodiammineplatinum(II) (cis- and trans-DDP) are reported. These two agents are excellent candidates for such studies since cis-DDP is an established potent antitumor agent while the trans-isomer exhibits little antitumor activity. The KB tumor cell population in chambers from the cis-DDP-treated animals decreased while the cell population in chambers from the trans-DDP-treated animals increased. Cytotoxicity data obtained in the study are similar to results from in vivo studies. The results of continuing studies with /sup 117m/Sn, /sup 123m/Te, /sup 75/Se, /sup 11/C, and /sup 195m/Pt-labeled agents are also described. A series of five /sup 117m/Sn-labeled steroids containing a variety of structural modifications have been prepared. Future tissue distribution studies in rats will determine the potential usefulness of these agents for adrenal imaging applications. Based upon our studies with /sup 75/Se-labeled steroids (adrenal imaging) and fatty acids (myocardial imaging), the potential use of the /sup 73/Se-labeled agents for emission computerized axial tomographic applications is also discussed. Calculations of the estimated radiation dose to humans from two /sup 123m/Te-labeled steroids which suggest the potential clinical usefulness of these agents for adrenal visualization have been completed. Patient studies have continued with /sup 11/C-aminocyclobutanecarboxylic acid (ACBC) and /sup 11/C-tryptophan. Continuing studies with /sup 195m/Pt-labeled antitumor agents are also reported. (ERB)
Date: August 1, 1979
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Health and safety research division. Nuclear medicine technology progress report for period ending March 31, 1979

Description: The preparation of a unique class of trimethyltin-substituted steroids is described that were designed because of the potential use of the /sup 117m/Sn-labeled analogs for adrenal imaging. The trimethyltin-substituted steroids were readily prepared on the microscale in yields ranging from 40 to 80%. Studies with the /sup 123m/Te-labeled fatty acids have continued, and radiolabeled 6-telluraheptadecanoic acid and 11-telluraheptadecanoic acid have shown pronounced heart uptake in rats. These results suggest that the position of the tellurium heteroatom has little effect on the heart uptake of the telluraheptadecanoic acids. Interest in the potential use of /sup 73/Se-labeled agents for tomographic imaging applications has resulted in the preparation of several /sup 75/Se-labeled compounds for preliminary tissue distribution studies in rats. Significant heart uptake was observed with /sup 75/Se-labeled-9-selenoheptadecanoic acid, suggesting that the various structural features affecting heart uptake of seleno fatty acids should also be explored. In addition, /sup 75/Se-labeled 24-(isopropyl seleno)-chol-5-en-3..beta..-ol was prepared and showed pronounced adrenal uptake in rats. The results of continuing studies with /sup 11/C-labeled amino acids in a collaborative project with the Oak Ridge Associated Universities (ORAU) are also described. Recent patient studies at ORAU have established that /sup 11/C-DL-tryptophan is superior to /sup 11/-DL-valine for pancreatic visualization by positron emission tomography. Nitrogen-13 was prepared for the first time in the ORNL 86-inch cyclotron and converted to /sup 13/N-ammonia that was used successfully to visualize dog hearts. (ERB)
Date: August 1, 1979
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Selenium and tellurium as carbon substitutes

Description: This review has summarized structure-activity studies with /sup 75/Se- and /sup 123m/Te-labeled radiopharmaceuticals in which the selenium or tellurium heteroatom has been inserted between carbon-carbon bonds. The agents that have been investigated in most detail include steroids for adrenal imaging and long-chain fatty acids, and a variety of other unique agents have also been studied. Because of the great versatility of the organic chemistry of selenium and tellurium, there is continuing interest in the preparation of radiopharmaceuticals labeled with /sup 75/Se, /sup 73/Se, and /sup 123m/Te. There are two important factors which will determine the extent of future interest in such agents. These include the necessity of a decrease in the cost of highly enriched /sup 122/Te to make the reactor production of /sup 123m/Te cost effective. In addition, the potential preparation of large amounts of /sup 73/Se should stimulate the development of /sup 73/Se-labeled radiopharmaceuticals.
Date: January 1, 1980
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Nuclear medicine technology progress report for quarter ending March 31, 1978

Description: Progress is reported for the applications of /sup 11/C, /sup 195m/Pt, and /sup 75/Se. Further human clinical trials with /sup 11/C-1-aminocyclobutane carboxylic acid and /sup 11/C-DL-tryptophan are reported, and batch production of the /sup 11/C-DL-tryptophan has increased twofold to 300 mCi. Detailed studies of the effect of the method of administration of /sup 195m/Pt-labeled cis-dichlorodiammine platinum (II) on the tissue distribution and retention of /sup 195m/Pt are reported. Selenium-75-labeled ..beta..-aminoethyl selenosulfate has been prepared as a potential myocardial imaging agent. The ORIS-11 version 01 has been tested successfully on a clinical Gamma-11 nuclear medical imaging system at Vanderbilt University.
Date: July 1, 1978
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Nuclear medicine technology. Progress report, quarter ending March 31, 1980

Description: The successful detection of experimentally produced myocardial infarctions in rats and dogs using /sup 123m/Te-9-telluraheptadecanoic acid (9-(/sup 123m/Te)-THDA) is described. Preferential localization of radioactivity in normal myocardial tissue of rats that had experimentally produced infarctions was also demonstrated by tissue distribution studies following injection of 9-(/sup 123m/Te)-THDA. The effects of chain length on the myocardial uptake of /sup 75/Se-labeled long-chain fatty acids was also studied further. Selenium-75-labeled 13-selenaheneicosonic acid (H/sub 3/C-(CH/sub 2/)/sub 7/-/sup 75/Se-(CH/sub 2/)/sub 11/-COOH, 13-(/sup 75/Se)-SHCA) shows the highest heart uptake in rats of the agents studied. These results indicate that myocardial imaging may be possible with 13-(/sup 75/Se)-SHCA and also suggest that potential positron emission tomography of the myocardium with the /sup 73/Se-labeled agent should be explored. The results of continuing studies with /sup 11/C and /sup 195m/Pt-labeled agents are also described. A variety of /sup 11/C-labeled amino acids were prepared and tested as pancreas and tumor localizing agents in a Medical Cooperative Program with the Oak Ridge Associated Universities. The microscale synthesis of /sup 195m/Pt-labeled cis-dichloro-trans-dihydroxy-bis-(isopropylamine)platinum(IV) (/sup 195m/Pt-CHIP) was developed further and preliminary tissue distribution studies with this important second-generation antitumor drug were completed in rats. Platinum-195m-labeled cis-dichlorodiammineplatinum(II) (/sup 195m/Pt-cis-DDP) was supplied for testing to a number of Medical Cooperative Programs. Studies of arsenic trioxide (As/sub 2/O/sub 3/) toxicity for human cells in the diffusion chamber assay system have continued. Further investigation of this arsenic-induced cytotoxicity has demonstrated a linear dose-response relationship and a difference in the permanence of the growth inhibitory effect using different doses.
Date: October 1, 1980
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

(Coordinated research programs in nuclear medicine)

Description: The traveler visited the Clinic for Nuclear Medicine at the University of Bonn, West Germany, to review, organize, and plan collaborative studies. He also met with the editorial board of the journal NucCompact -- European/American Communications in Nuclear Medicine, on which he serves as US editor. He also visited colleagues at the Cyclotron Research Center (CRC) at the University of Liege, Belgium, to coordinate clinical applications of the ultrashort-lived iridium-191m radionuclide obtained from the osmium-190/iridium-191m generator system. The traveler planned and coordinated continuing collaboration with colleagues at the CRC for further applications of this generator system. He also visited the University of Metz, Metz, France, to organize a three-center project for the synthesis and evaluation of various receptor-specific cerebral imaging agents, involving the Oak Ridge National Laboratory (ORNL), CRC, and the University of Metz.
Date: October 3, 1990
Creator: Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Design, synthesis and evaluation of redox radiopharmaceuticals: a potential new approach for the development of brain imaging agents

Description: The fabrication and complete evaluation are described of a dihydropyridine in equilibrium pyridinium salt type redox system for the delivery of radioiodinated agents to the brain. The pivotal intermediate, N-succinimidyl (1-methylpyridinium iodide)-3-carboxylate was prepared by condensation of nicotinic acid and N-hydroxysuccinimide in the presence of dicyclohexylcarbodimide, followed by quaternization of III with methyl iodide. Tissue distribution studies of /sup 125/I-labeled 4-iodoaniline and the redox agents were performed in rats. (/sup 125/I)Iodoaniline initially showed moderate (0.58% dose/gm) brain uptake with subsequent release of the radioactivity from the brain. (/sup 125/I)Iodoaniline, when coupled to a dihydropyridine carrier showed higher uptake and retention in the brain. The (/sup 125/I)iodophenylethyl analogue showed uptake and retention in the brain to be very similar. Apparently the lipophilic agents cross the blood-brain barrier and are oxidized (quaternized) within the brain. The blood-brain barrier then prevents their release resulting in high uptake and retention in the brain and high brain:blood ratios. 11 refs., 3 figs.
Date: January 1, 1986
Creator: Srivastava, P.C. & Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Potential new approaches for the development of brain imaging agents for single-photon applications

Description: This paper describes new strategies for the brain-specific delivery of radionuclides that can be used to evaluate regional cerebral perfusion by single photon imaging techniques. A description of several examples of interesting new strategies that have recently been reported is presented. A new approach at this institution for the brain-specific delivery of radioiodinated iodophenylalkyl-substituted dihyronicotinamide systems is described which shows good brain uptake and retention in preliminary studies in rats. Following transport into the brain these agents appear to undergo facile intracerebral oxidation to the quaternized analogues which do not recross the intact blood-brain barrier and so are effectively trapped in the brain. 49 refs., 9 figs., 1 tab.
Date: January 1, 1984
Creator: Knapp, F.F. Jr. & Srivastava, P.C.
Partner: UNT Libraries Government Documents Department

Design and biological properties of iodine-123 labeled. beta. -methyl-branched fatty acids

Description: The synthetic strategy, synthesis, preclinical evaluation and potential clinical applications of 3-methyl-branched radioiodinated iodophenyl- and iodovinyl-substituted fatty acids are reviewed for use as myocardial imaging agents. 50 references, 6 figures. (ACR)
Date: January 1, 1984
Creator: Knapp, F.F. Jr. & Goodman, M.M.
Partner: UNT Libraries Government Documents Department

Design, synthesis and evaluation of 2-deoxy-2-iodovinyl-branched carbohydrates as potential brain imaging agents

Description: Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose (10) as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. 10 refs., 1 fig., 1 tab.
Date: January 1, 1986
Creator: Goodman, M.M.; Callahan, A.P. & Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

New radioiodinated methyl-branched fatty acids for cardiac studies

Description: The effects of 3-methyl-substitution on the heart retention and metabolism of 3-R,S-methyl-(BMIPP) and 3,3-dimethyl-(DMIPP) analogues of 15-(p-iodophenyl)-pentadecanoic acid (IPP) have been studied in rats. Methyl-substitution considerably increased the myocardial half-time values in fasted rats: IPP, 5 to 10 min; BMIPP, 30 to 45 min; DMIPP, 6 to 7 h. Because of the observed differences in the relative myocardial uptake and retention of these agents, an evaluation of the subcellular distribution profiles and the distribution of radioactivity within various lipid pools extracted from cell components was performed. Studies with DMIPP in fasted rats have shown high levels of the free fatty acid and only slow conversion to triglycerides. These data are in contrast to the rapid clearance of the straight chain IPP analogue and rapid incorporation into triglycerides. These data suggest that the prolonged myocardial retention observed with DMIPP in vivo may result from inhibition of US -oxidation. Subcellular distribution studies have shown predominate association of DMIPP and BMIPP with the mitochondrial and microsomal fractions, while IPP was primarily found in the cytoplasm. Because of the unique ''trapping'' properties and the high heart:blood ratios, ( STI)DMIPP should be useful for evaluation of aberrations in regional myocardial uptake. 7 refs., 9 figs., 1 tab.
Date: January 1, 1985
Creator: Knapp, F.F. Jr.; Ambrose, K.R. & Goodman, M.M.
Partner: UNT Libraries Government Documents Department

New radiohalogenated alkenyl tellurium fatty acids

Description: Radiolabeled long-chain fatty acids have diagnostic value as radiopharmaceutical tools in myocardial imaging. Some applications of these fatty acids are limited due to their natural metabolic degradation in vivo with subsequent washout of the radioactivity from the myocardium. The identification of structural features that will increase the myocardial residence time without decreasing the heart uptake of long-chain fatty acids is of interest. Fatty acids containing the tellurium heteroatom were the first modified fatty acids developed that show unique prolonged myocardial retention and low blood levels. Our detailed studies with radioiodinated vinyliodide substituted tellurium fatty acids demonstrate that heart uptake is a function of the tellurium position. New techniques of tellurium and organoborane chemistry have been developed for the synthesis of a variety of radioiodinated iodoalkenyl tellurium fatty acids. 9 refs., 3 figs., 2 tabs.
Date: January 1, 1987
Creator: Srivastava, P.C.; Knapp, F.F. Jr. & Kabalka, G.W.
Partner: UNT Libraries Government Documents Department

Incorporation of radiohalogens via versatile organometallic reactions: applications in radiopharmaceutical chemistry

Description: Factors that must be considered for the design of radiohalogenated radio-pharmaceuticals include the stability and availability of the substrate, the physical half-life of the radiohalogen and the in vivo stability of the radiolabel. Vinyl and phenyl radiohalogen bonds show more in vivo stability than the alkyl radiohalogen bonds. Consequently, a variety of methods suitable for the synthesis of tissue specific radiopharmaceuticals bearing a vinyl or phenyl radiohalogen have been developed involving the synthesis and halogenation of metallovinyl and phenyl intermediates. The halogens and metallation reactions include iodine and bromine and alanation, boronation, mercuration, stannylation, and thallation, respectively. 19 refs., 1 fig., 1 tab.
Date: January 1, 1985
Creator: Srivastava, P.C.; Goodman, M.M. & Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Microimaging studies of myocardial substrate utilization and perfusion in two models of non-coronary heart disease

Description: We have studied two animal models of non-coronary heart disease. The salt-sensitive Dahl strain hypertensive rats and their genetically matched normotensive controls and the cardiomyopathic BIO 53.58 (CM) strain Syrian hamsters with age and sex-matched RB strain controls. The CM strain hamster seems to be a very good model of human congestive cardiomyopathy and the Dahl strain hypertensive rats have also been found to be good models for studying the effects of hypertension on the myocardium. In our studies we compared the utilization of various metabolic substrates, viz., fatty acids, glucose analogs, and the early distribution of /sup 201/Tl, as an indicator of myocardial flow. The routine studies involving dissection of animals for assaying the radioactivity following the injection of radiopharmaceuticals is not suitable for assessing regional changes in metabolism and flow. The use of quantitative autoradiographic microimaging (ARG) enables the visualization of discrete regional as well as global changes from normal and to quantitate them. This paper describes the methodology and results of these investigations. 14 refs., 5 figs.
Date: January 1, 1987
Creator: Som, P.; Oster, Z.H. & Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Production of tungsten-188 and osmium-194 in a nuclear reactor for new clinical generators

Description: Rhenium-188 and iridium-194 are potential candidates for radioimmunotherapy with monoclonal antibodies directed against tumor-associated antigens. Both nuclei are short-lived and decay by high energy {Beta}{minus} emission. In addition, both nuclei emit {gamma}-rays with energy suitable for imaging. An important characteristics is availability of {sup 188}Re and {sup 194}Ir from decay of reactor-produced parents ({sup 188}W and {sup 194}Os, respectively) in convenient generator systems. The {sup 188}W and {sup 194}Os are produced by double neutron capture of {sup 186}W and {sup 192}Os, respectively. The large scale production yields of {sup 188}W in several nuclear reactors will be presented. We also report a new management for the cross-section of {sup 193}Os(n,{gamma}){sup 194}Os reaction and discuss the feasibility of producing sufficient quantities of {sup 194}Os. 17 refs., 1 fig., 2 tabs.
Date: January 1, 1991
Creator: Mirzadeh, S.; Knapp, F.F. Jr. & Callahan, A.P.
Partner: UNT Libraries Government Documents Department

Use of Rhenium-188 Liquid-Filled Balloons for Inhibition of Coronary Restenosis After PTCA - A New Opportunity for Nuclear Medicine

Description: Although the use of ionizing radiation for the treatment of benign lesions such as keloids has been available for nearly one hundred years, only recently have the cost effective benefits of such technology for the inhibition of arterial restenosis following controlled vessel damage from balloon angioplasty been fully realized. In particular, the use of balloons filled with solutions of beta-emitting radioisotopes for vessel irradiation provide the benefit of uniform vessel irradiation. Use of such contained ("unsealed") sources is expected to represent a new opportunity for nuclear medicine physicians working in conjunction with interventional cardiologists to provide this new approach for restenosis therapy.
Date: May 13, 1999
Creator: Knapp, F. F., Jr.; Spencer, R.H. & Stabin, M.
Partner: UNT Libraries Government Documents Department

The development and use of radionuclide generators in nuclear medicine -- recent advances and future perspectives

Description: Although the trend in radionuclide generator research has declined, radionuclide generator systems continue to play an important role in nuclear medicine. Technetium-99m obtained from the molybdenum-99/technetium-99m generator system is used in over 80% of all diagnostic clinical studies and there is increasing interest and use of therapeutic radioisotopes obtained from generator systems. This paper focuses on a discussion of the major current areas of radionuclide generator research, and the expected areas of future research and applications.
Date: March 1998
Creator: Knapp, F. F., Jr.
Partner: UNT Libraries Government Documents Department

Nuclear medicine program. Progress report for quarter ending June 30, 1995

Description: In this report we describe the first synthesis of the (-)(-) and (-)(+) isomers of 1-azabicyclo oct-3-yl {alpha}-(1-fluoropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetate ({open_quotes}FQNPe{close_quotes}). Earlier studies with the racemic FQNPe mixture had demonstrated high in vitro binding affinity for the muscarinic-cholinergic receptor and showed that pre-treatment of rats with this new agent significantly blocked receptor localization of subsequently injected -Z-(-,-)-IQNP. Because of the potential important use of fluorine-18-labeled analogues for clinical evaluation of changes in muscarinic-cholinergic receptors by positron emission tomography (PET), we have now synthesized the diastereomeric isomers of FQNPe. Multi-gram quantities of ethyl-{alpha}- (1-chloropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetate were prepared and then saponified into the racemic {alpha}-(1-chloropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetic acid mixture. The racemic acid was resolved into (-)- and (+)-{alpha}-(1-chloropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetic acid enantiomers by isolation of the (-) salt of (S-)-(-)-{alpha}-methylbenzylamine and the (+) salt of (R)-(+)-{alpha}-methylbenzylamine. The resolved (-)- ([{alpha}]{sub D} = -12.1{degrees}, c = 5.8, chloroform) and (+)-acetic acids ([{alpha}]{sub D} = + 11.6{degrees}, c = 6.0, chloroform) were fully characterized and then converted to the enantiomeric ethyl-{alpha}-(1-fluoropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetates by a four-step reaction sequence. The (-)- and (+)-ethyl-{alpha}-(1-fluoropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetates were then each transesterified with (-)-quinuclidinol to form the (-)(-) FQNPe and (-)(+) FQNPe diastereomers. These diastereomeric esters will now be evaluated in in vitro studies. The availability of the substrates for preparation of the fluorine-18-labeled enantiomers will now allow evaluation of the radiolabeled compounds in animals.
Date: September 1, 1995
Creator: Knapp, F.F. Jr.; Ambrose, K.R. & Beets, A.L.
Partner: UNT Libraries Government Documents Department

Interim report on intrathoracic radiotherapy of human small-cell lung carcinoma in nude mice with Re-188-RC-160, a radiolabeled somatostatin analogue

Description: The purpose of this study was to evaluate the therapeutic efficacy of Re-188-RC-160 in experimental models of human small cell lung carcinomas which mimic the clinical presentation. In the experimental model, cells from the human small cell lung carcinoma cell line NCI-H69 cells were inoculated into the thoracic cavity of athymic mice and rats. Subsequently, the biodistribution of Re-188-RC-160 after injection into the pleural cavity, a radiolabeled somatostatin analogue, was monitored as was the effect on the subsequent growth of tumors. The results presented here, and which are a part of a larger series of studies, suggest that Re-188-RC-160 can be effectively used in this animal model to restrict the growth of small cell lung carcinoma in the thoracic cavity.
Date: July 1, 1995
Creator: Zamora, P.O.; Bender, H.; Biersack, H.J. & Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Synthesis and biological evaluation of (E)-19-iodo-3,3-dimethyl-18-nonadecenoic acid, a new dimethyl-branched long-chain fatty acid to evaluate regional myocardial fatty acid uptake

Description: The synthetic method for the preparation of (E)-19-iodo-3,3-dimethyl-18-nonadecenoic acid (DMIVN) involved introduction of substituents into the 2- and 5-positions of a thiophene ring followed by sulfur extrusion of a 2,5-dialkyl thiophene derivative to provide a key 3,3-dimethyl-branched fatty acid intermediate, 17-iodo-3,3-dimethylheptadecanoic acid. Myocardial subcellular distribution studies of the /sup 125/I-labeled DMIVN in fasted rats showed a higher association of radioactivity with the microsomes when compared to the results obtained with the 19-carbon straight chain analogue. With the nonfasted rats the distribution profiles of the two analogues showed differences that seemed to correlate with the differences in myocardial retention that fasting and feeding can induce. 5 refs., 3 figs., 2 tabs.
Date: January 1, 1986
Creator: Goodman, M.M.; Ambrose, K.R.; Neff, K.H. & Knapp, F.F. Jr.
Partner: UNT Libraries Government Documents Department

Efficient microscale preparation of tin-117m-tin tetrachloride-a pivotal intermediate for the synthesis of tin-117m-labeled radiopharmaceuticals

Description: A microscale technique has been developed for the preparation of /sup 117m/SnCl/sub 4/. The radiolabeled tin tetrachloride is an important intermediate for the synthesis of /sup 117m/Sn-labeled organic radiopharmaceuticals. The flow-through system involves high temperature chlorination of metallic /sup 117m/Sn with subsequent cryogenic collection of the /sup 117m/SnCl/sub 4/ in a special reaction vessel. This vessel can then be used for the conversion of the tin tetrachloride to various useful intermediates. The reactions that have been studied include the formation of tetraalkyl and tetraaryltin compounds by reaction of SnCl/sub 4/ with Grignard or alkyl and aryl lithium reagents (SnCl/sub 4/ ..-->.. R/sub 4/Sn or Ar/sub 4/Sn). In addition, by stoichiometric control, the comproportionation of SnCl/sub 4/ with tetramethyltin can yield any one of the mixed methylchlorotin intermediates, MeSnCl/sub 3/, Me/sub 2/SnCl/sub 2/, or Me/sub 3/SnCl. These products are important intermediates for the preparation of /sup 117m/Sn-labeled steroids, fatty acids, amino acids, barbituates, and a variety of other potentially useful agents.
Date: January 1, 1979
Creator: Woo, D.V.; Knapp, F.F. Jr.; Butler, T.A. & Callahan, A.P.
Partner: UNT Libraries Government Documents Department

Tellurium-123m-labeled isosteres of palmitoleic and oleic acids show high myocardial uptake

Description: These studies were directed at determining if the telluro fatty acids prepared by the isosteric replacement of the ..delta../sup 9/-double bonds of oleic and palmitoleic acids with /sup 123m/Te would show heart uptake in rats. The isostere of palmitoleic acid, 9-tellurapentadecanoic acid(II), was prepared by basic hydrolysis of the product formed by the coupling of /sup 123m/Te-sodium hexyl tellurol with methyl-8-bromooctadecanoate. Similarly, the isostere of oleic acid, 9-telluraheptadecanoic acid(IV), was prepared by the same route beginning with the reaction of /sup 123m/Te-sodium octyl tellurol with methyl-8-bromooctadecanoate. Both /sup 123m/Te-(II) and /sup 123m/Te-(IV) showed remarkably high heart uptake in rats (2 to 3% dose/gm) ten minutes after intravenous administration, and the heart/blood ratios were high (20-30/1). Finally, the hearts of rats injected with /sup 123m/Te-(IV) have been clearly imaged with a rectilinear scanner.
Date: January 1, 1979
Creator: Knapp, F.F. Jr.; Ambrose, K.R.; Callahan, A.P.; Grigsby, R.A. & Irgolic, K.J.
Partner: UNT Libraries Government Documents Department