Propylene amine oxime (PnAO) forms a neutral lipid soluble complex with 99mTc. 99mTc-PnAO can be prepared by simple reduction of 99mTc-pertechnetate with stannous ion in the presence of excess PnAO in saline at or near neutral pH. This agent will passively penetrate biological membranes including the intact blood-brain barrier (BBB) as evidenced by the high brain uptake observed shortly after IV injection. The first-pass extraction efficiency in baboons was estimated to be 80% at normal blood flow. This agent or a derivatized form of 99mTc-PnAO may be useful in assessment of regional cerebral blood flow (rCBF) in humans.

Synthesis and characterization of a new pentadentate amine-oxime ligand, 3,3,11,11-tetramethyl-7-benzyl-4,7,10-triazatridecane-2,12- dionedioxime is reported. The technetium complexes of this ligand was formed by direct reduction of TcO4- in the presence of the ligand at pH 9. The radiochemical yield of the complex is greater than 95% with 10(-7) M 99TcO4-. The technetium complex formed is a positively charged chelate that elutes as a single peak on a reverse phase HPLC. Biodistribution studies in rats showed an uptake of 1.4% of the injected activity at 15 sec p.i. in heart, but the wash-out was fast. The high radiochemical purity and stability of this 99mTc-chelate indicate that these types of chelates hold potential for development of bifunctional chelating agents (BFCAs).

Weeks, S. A.; Muirhead, K. A.; McIlvain, H. B.; McDevitt, M. R.; Sheth, K. A.; Troutner, D. E.; Horan, P. K. Author Information

Palladium(II) complexes of an imine-thiophene ligand N,N′ bis(1-methylenethiophene)-1,3-diaminopropane and an amine-phenol ligand N,N′-bis(2-hydroxybenzyl)1,3-diamino-2,2-dimethylpropane were synthesized by reacting K2PdCl4 with alcoholic solutions of the ligands. X-ray structures of the complexes were determined using data from a CAD-4 Nonius diffractometer (MoKα radiation). The structures were solved by conventional methods resulting inR factors of 0.044 and 0.061 using 1841 and 2241 independent reflections, respectively. Crystal data: Complex I, orthorhombic, space groupPbca,a=11.323(2),b=14.819(2),c=23.873(3)Å,V=4006(1)Å3,Z=8. Complex II: Space groupP21/c,a=9.169(2),b=31.920(4),c=8.902(6),β=90.38(2)°,V=2605(1)Å3.Z=4. Both complexes showed coordination of the ligands through the nitrogens only while the sulphur and the oxygen atoms were uncoordinated. Square planar coordination is completed bycis chloro ligands.

We report the labeling of human gamma globulin with the 105Rh complex of a new pentadentate bifunctional ligand, 1,7-bis(2-hydroxybenzyl)-4-(p-aminobenzyl)diethylenetriamine. Complexes of this ligand with 105Rh were prepared by refluxing rhodium carrier spiked with 105Rh at pH9 in bicarbonate buffer. The complex was treated with an excess concentration of thiophosgene to prepare the isothiocyanate derivative which was extracted into CHCl3. The CHCl3 extract was dried and dissolved in DMF and reacted with a borate solution of human gamma globulin. Labeling yields were generally high and varied from 73% to 93%, depending upon the concentration of human gamma globulin and the isothiocyanate derivative of the complex used. The overall recovery of rhodium activity varied from 59% to 75% without taking into account activity lost due to decay. The conjugation reaction was complete by 4 h. From 0.4 to 8.5 atoms of Rh could be incorporated per molecule of protein by this method. The activated isothiocyanate complex did not show any degradation when stored at room temperature for up to 4 days and then used for conjugation.

We have synthesized amine-phenol ligands of the general structure bis-(2-hydroxybenzylamino)X, where X is a hydrocarbon backbone. Radiochemical studies of 99Tc and 99mTc complexes were done at total technetium concentrations of 0.1–100 μM. Complex yields were measured by ascending solvent paper chromatography, TLC, solvent extraction and reversed phase HPLC. Complexes were readily formed and were neutral and lipophilic. Lipophilicity was enhanced by the addition of methyl groups to the carbon backbone. Similar complexes formed from the corresponding Schiff base ligands were less lipophilic and were formed in lower yields.

A bifunctional ligand 4-(p-aminobenzyl)-diethylenetriamine has been synthesized. 105Rh complexes with this ligand were prepared with an overall yield of 79% at pH 9.0 in bicarbonate buffer. The preformed complex was converted to the isothiocyanate derivative using thiophosgene. Conjugation yields of 75% with IgG and 85% with HSA could be obtained for a 4 h conjugation reaction. Affinity chromatography of human-IgG coupled to the rhodium complex in an anti-human IgG agarose gel indicated no denaturation of the labeled protein. The procedure reported here can be adapted for the preparation of 105Rh-labeled antibodies for therapeutic applications.

A complex of rhodium with the bifunctional chelating agent 4-p-toluic acid-diethylenetriamine has been prepared using 105Rh as a tracer. This bifunctional chelate has been conjugated to human serum albumin and human IgG. Radiochemical conjugation yields are ∼30–40% and RhIgG ratios as high as 2.5 are observed.

Journal of Labelled Compounds and RadiopharmaceuticalsVolume 26, Issue 1-12 p. 179-181 Symposium Abstract Production of 105Rh by the szilard-chalmers process with ruthenium acetylacetonate Y.K. Wong, Y.K. Wong Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this authorA.R. Ketring, A.R. Ketring Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this authorJ.M. Lo, J.M. Lo Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this authorD.E. Troutner, D.E. Troutner Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this author Y.K. Wong, Y.K. Wong Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this authorA.R. Ketring, A.R. Ketring Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this authorJ.M. Lo, J.M. Lo Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this authorD.E. Troutner, D.E. Troutner Department of Chemistry, University of Missouri, Columbia, MO 65211Search for more papers by this author First published: January 1989 https://doi.org/10.1002/jlcr.2580260179Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume26, Issue1-12January 1989Pages 179-181 RelatedInformation

AbstractThe Tc(V) complexes (I)‐(III) are prepared by the reduction of ammonium pertechnetate with stannous ion in the presence of the corresponding ligand in aqueous medium at pH 8‐9. The length of the hydrocarbon backbone of the amine oxime ligand is varied to effect chemical changes in the complexes.

A series of neutral technetium(V) complexes have been synthesized (TcO(AO)/sub 2/, TcOEn(AO)/sub 2/, TcO/sub 2/Bn(AO)/sub 2/, and TcO/sub 2/Pent(AO)/sub 2/) in which the length of the hydrocarbon backbone of the amine oxime ligand is varied to effect chemical changes in the resultant complexes. Pn(AO)/sub 2/, 3,3,9,9-tetramethyl-4,8-diazaundecane-2,10-dione dioxime, is the prototype for these ligands. In this series of technetium(V) complexes in which the overall ring size is varied, both monooxo and trans-dioxo cores are observed, and an unusual eight-member chelate ring with the technetium(V) center is found with TcO/sub 2/Pent(AO)/sub 2/. TcO/sub 2/Pent(AO)/sub 2/ x CHCl/sub 3/, TcCl/sub 6/O/sub 4/C/sub 17/H/sub 33/, crystallizes in the triclinic system, space group P anti 1, with a = 1.418 (2) A, b = 13.940 (7) A, c = 18.992 (10) A, ..cap alpha.. = 69.29 (4)/sup 0/, ..beta.. = 90.00 (3)/sup 0/, ..gamma.. = 83.69 (3)/sup 0/, and Z = 4. TcOEn(AO)/sub 2/, TcO/sub 3/N/sub 4/C/sub 12/H/sub 23/, crystallizes in the orthorhombic system, space group Pbca, with a = 11.581 (2) A, b = 12.596 (4) A, c = 21.155 (3) A, and Z = 8.

Since last year we have: continued the synthesis of pentadentate bifunctional chelating agents based on diethylene triamine; studied the chelation Rh-105, Au-198 (as model for Au-199) and Tc-99m with these agents as well as chelation of Pd-109, Cu-67, In-111, and Co-57 with some of them; synthesized a new class of potential bifunctional chelating agents based on phenylene diamine; investigated the behavior of Au-198 as a model for Au-199; begun synthesis of bifunctional chelating agents based on terpyridly and similar ligands; and continued attempts to produce tetradentate bifunctional chelates based on diaminopropane. Each of these will be addressed in this report.

AbstractThe neutral and lipophilic Tc(V)tit1e complexes (I) are synthesized by the reduction of ammonium pertechnetate with stannous tartrate in the presence of the appropriate methyl‐substituted 4,8‐diazaundecane‐1,10‐dione dioximes.