uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Sjöberg, Stefan
Alternative names
Publications (10 of 19) Show all publications
Naeslund, C., Ghiramai, S. & Sjöberg, S. (2005). Enantioselective synthesis of m-carboranylalanine, a boron-rich analogue of phenylalanine. Tetrahedron, 61, 1181-1186
Open this publication in new window or tab >>Enantioselective synthesis of m-carboranylalanine, a boron-rich analogue of phenylalanine
2005 (English)In: Tetrahedron, Vol. 61, p. 1181-1186Article in journal (Refereed) Published
Abstract [en]

The enantiomers of the highly lipophilic a-amino acid m-carboranyl-alanine [3-(1.7-dicarba-closo-dodecaborane(12)-1-yl)-2-aminopropanoic acid], a carborane containing analogue of phenylalanine, have been synthesised via hydroxyamination of the N-acyl derivative formed from 3-(m-carboranyl)propionoic acid [3-(1.7-dicarba-closo-dodeca-borane(12)-1-yl)-2-propanoic acid] and Oppolzer's camphor sultam. The enantiomeric excess of both enantiomers of the amino acid was >98%. (S)-Configuration was assigned to the (+)-enantiomer (ch3Oh, 589 nm).

Keywords
m-Carboranylalanine, Absolute configuration, Carborane, Boron neutron capture therapy, Asymmetric synthesis, Highly lipophilic amino acid
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-70005 (URN)doi:10.1016/j.tet.2004.11.045 (DOI)
Available from: 2005-04-13 Created: 2005-04-13 Last updated: 2011-01-12
Mume, E., Orlova, A., Larsson, B., Nilsson, A.-S., Nilsson, F. Y., Sjöberg, S. & Tolmachev, V. (2005). Evaluation of ((4-Hydroxyphenyl)ethyl)maleimide for Site-Specific Radiobromination of Anti-HER2 Affibody. Bioconjugate chemistry, 16(6), 1547-1555
Open this publication in new window or tab >>Evaluation of ((4-Hydroxyphenyl)ethyl)maleimide for Site-Specific Radiobromination of Anti-HER2 Affibody
Show others...
2005 (English)In: Bioconjugate chemistry, ISSN 1043-1802, E-ISSN 1520-4812, Vol. 16, no 6, p. 1547-1555Article in journal (Refereed) Published
Abstract [en]

Affibody molecules are a new class of small phage-display selected proteins using a scaffold domain of the bacterial receptor protein A. They can be selected for specific binding to a large variety of protein targets. An affibody molecule binidng with high affinity to a tumor antigen HER2 was recently developed for radionuclide diagnostics and therapy in vivo. The use of hte positron-emitting nuclide 76Br(T½ = 16.2 h) could imporve the sensitivity of detection of HER2-expressing tumors. A site-specific radiobromination o fa cysteine-containing variant of the anti-HER2 affibody, (ZHER2:4)2-Cys, using ((4-hydroxpyphenyl)ethyl)maleimide (HPEM), was evaluated in this study. It was found that HPEM can be radiobrominated with an efficiency of 83+0.4% and thereafter coupled to freshly reduced conjugate to exceed 97%. The label was stable against challenge with large excess of nonlabeled bromide and in a high molar strengt solution. In vitro cell tests demonstraded that radiobrominated affibody binds specifically to the HER2-expressing cel-line, SK-OV-3. Biodistribution studies in nude mice bearing SK-OV-3 xenografts have shown tumor accumulation of 4.8 ? 2.2% IA/g and good tumor-to-normal tissue ratios.

Keywords
Animals, Antigens; Neoplasm/analysis/metabolism, Binding Sites, Bromine Radioisotopes/*chemistry, Cell Line; Tumor, Humans, Maleimides/chemistry, Mice, Mice; Nude, Neoplasms; Experimental/pathology, Peptide Library, Peptides/chemistry/*pharmacokinetics, Protein Interaction Mapping, Radiopharmaceuticals/*chemical synthesis/*pharmacokinetics, Receptor; erbB-2/analysis/*metabolism, Research Support; Non-U.S. Gov't, Staphylococcal Protein A/chemistry, Tissue Distribution, Transplantation; Heterologous
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-74804 (URN)10.1021/bc050056o (DOI)16287254 (PubMedID)
Available from: 2006-06-29 Created: 2006-06-29 Last updated: 2017-12-14Bibliographically approved
Winberg, K. J., Mume, E., Tolmachev, V. & Sjöberg, S. (2005). Radiobromination of closo-carboranes using palladium-catalyzed halogen exchange. Journal of labelled compounds & radiopharmaceuticals, 48(3), 195-202
Open this publication in new window or tab >>Radiobromination of closo-carboranes using palladium-catalyzed halogen exchange
2005 (English)In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 48, no 3, p. 195-202Article in journal (Refereed) Published
Keywords
halogen exchange, carboranes, [76Br]bromide, labelling, palladium, catalyst
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-69999 (URN)10.1002/jlcr.914 (DOI)
Available from: 2005-04-13 Created: 2005-04-13 Last updated: 2017-11-21Bibliographically approved
Ghirmai, S., Mume, E., Lundqvist, H., Tolmachev, V. & Sjöberg, S. (2005). Synthesis and radioiodination of some 9-aminoacridine derivatives for potential use in radionuclide therapy. Journal of labelled compounds & radiopharmaceuticals, 48(12), 855-871
Open this publication in new window or tab >>Synthesis and radioiodination of some 9-aminoacridine derivatives for potential use in radionuclide therapy
Show others...
2005 (English)In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 48, no 12, p. 855-871Article in journal (Refereed) Published
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-83610 (URN)10.1002/jlcr.960 (DOI)
Available from: 2006-11-07 Created: 2006-11-07 Last updated: 2017-12-14Bibliographically approved
Ghirmai, S., Mume, E., Tolmachev, V. & Sjöberg, S. (2005). Synthesis and radioiodination of some daunorubicin and doxorubicin derivatives. Carbohydrate Research, 340(1), 15-24
Open this publication in new window or tab >>Synthesis and radioiodination of some daunorubicin and doxorubicin derivatives
2005 (English)In: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 340, no 1, p. 15-24Article in journal (Refereed) Published
Abstract [en]

Daunorubicin and doxorubicin are efficient agents for cancer treatment. Their clinical efficacy is, however, hampered by their indiscriminant toxicity. This problem may be circumvented by encapsulating the drugs in liposomes and selectively targeting the tumor cells using tumor targeting agents. Furthermore, the antitumor effect could be enhanced by attaching the Auger electron emitter, 125I, to daunorubicin an ddoxorubicin derivatives. In this context a number of ester, amide, and amine derivatives of daunorubicin an ddoxorubicin were synthesized. Benzoic acid ester derivatives of daunorubicin were synthesized by nucleophilic esterification of the 14-bromodaunorubicin with the potassium salt of the corresponding benzoic acid, resulting in good yields. Nicotinic acids and benzoic acids, activated with a succinimidyl group, were coupled to the amino group of daunorubicien to give the corresponding amide derivatives. Amine derivatives were obtained by the reductive amination of aromatic aldehydes with daunorubicin hydrochloride. The stannylated ester and amide derivatives were uses as precursors for radioiodination. Radiolabeling with 125I was performed using chloroamine-T as an oxidant. The optimized labeling resulted in high radiolabeling yields (85-95%) of the radioiodinated daunorubicin and doxorubicin derivatives. Radioiodination of the amines was conducted at the ortho position of the activated phenyl rings providing moderate radiochemical yields (55-75%).

Keywords
Daunorubicin, Doxorubicin, Radioiodination, 125I, Chloramine-T
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-70001 (URN)doi:10.1016/j.carres.2004.10.014 (DOI)15620662 (PubMedID)
Available from: 2006-06-29 Created: 2006-06-29 Last updated: 2017-11-21Bibliographically approved
Sivaev, I. B., Starikova, Z. A., Petrovskii, P. V., Bregadze, V. I. & Sjöberg, S. (2005). The synthesis of functional derivatives of the [1-CB9H10]-anion by Brellochs reaction. Journal of Organo metallic Chemistry (690), 2790-2795
Open this publication in new window or tab >>The synthesis of functional derivatives of the [1-CB9H10]-anion by Brellochs reaction
Show others...
2005 (English)In: Journal of Organo metallic Chemistry, no 690, p. 2790-2795Article in journal (Refereed) Published
Abstract [en]

Reactions of decarborane with various aldehydes in alkaline media were studied. The reactions with HCOH and 2-MeOC6H4-CHO give the corresponding arachno-carboranes [6-R-arachno-CB9H13]-(R=H, C6H4-2-OMe), whereas the reactions with C6H5CHO, 4-BrC6H4CHO, 4-MeCONHC6H4CHO and 2-SC4H3CHO result in the nido-carboranes [6-R-nido-CB9H11]-(R=C6H5, C6H4-4Br, C6H4-4-NHCOMe, 2-SC4H3). Both the arachno- and nido-carboranes can be easily oxidized with elemental iodine in an alkaline aqueous solution giving the corresponding closo-derivatives [2-R-closo-2-CB9H9]-. These closo-2isomers, under heating in solution, undergo rearrangement to more thermodynamically favorable closo-1-isomers [1-R-closo-1-CB9H9]-. The structure of (Bu4N)[1-(4-BrC6H4)-1-CB9H9] was determined using single crystal X-ray diffraction.

Keywords
1-carba-closo-decaborate, Derivatives, Synthesis, X-ray structure
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-73834 (URN)doi:10-1016-/j.jorganchem.2005.01.052 (DOI)
Available from: 2005-06-30 Created: 2005-06-30 Last updated: 2011-01-11
Beletskaya, I., Bregadze, V., Ivushkin, V., Petrovskii, P., Sivaev, I., Sjöberg, S. & Zhigareva, G. (2004). New B-substituted derivatives of m-carborane, p-carborane, and cobalt bis(1,2-decarbollide) anion. J. Organomet. Chem. (689), 2920
Open this publication in new window or tab >>New B-substituted derivatives of m-carborane, p-carborane, and cobalt bis(1,2-decarbollide) anion
Show others...
2004 (English)In: J. Organomet. Chem., no 689, p. 2920-Article in journal (Refereed) Published
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-69961 (URN)
Available from: 2005-04-12 Created: 2005-04-12 Last updated: 2011-01-12
Tolmachev, V., Bruskin, A., Sjöberg, S., Carlsson, J. & Lundqvist, H. (2004). Preparation, radioiodination, and in vitro evaluation of a nido-carborane-dextran conjugate, a potential residualizing label for tumor targeting proteins and peptides. Journal of Radioanalytical and Nuclear Chemistry, 261(1), 107-112
Open this publication in new window or tab >>Preparation, radioiodination, and in vitro evaluation of a nido-carborane-dextran conjugate, a potential residualizing label for tumor targeting proteins and peptides
Show others...
2004 (English)In: Journal of Radioanalytical and Nuclear Chemistry, ISSN 0236-5731, E-ISSN 1588-2780, Vol. 261, no 1, p. 107-112Article in journal (Refereed) Published
Abstract [en]

Polysaccharides are not degradable by proteolytic enzymes in lysosomes and do not diffuse through cellular membranes. Thus, attached to an internalizing, targeting protein, such polysaccharide linkers, will remain intracellularly after protein degradation. They can be labeled with halogens and provide then a so called residualizing label. Such an approach improves tumor-to-non-tumor radioactivity ratio and, consequently, the results of radionuclide diagnostics and therapy. In this study we present a new approach to obtain a stable halogenation of the polysaccharide dextran using 7-(3-amino-propyl)-7,8-dicarba-nido-undecaborate (-) (ANC). Dextran T10 was partially oxidized by metaperiodate, and ANC was coupled to dextran by reductive amination. The conjugate was then labeled with 125I using either Chloramine-T or IodoGen as oxidants. Labeling efficiency was 69-85%. Stability of the label was evaluated in rat liver homogenates. Under these conditions, the ANC-dextran conjugate was found to be more stable than labeled albumin, which was used as a control protein.

National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-69963 (URN)10.1023/B:JRNC.0000030942.76919.6b (DOI)
Available from: 2006-05-17 Created: 2006-05-17 Last updated: 2017-11-21Bibliographically approved
Winberg, K. J., Persson, M., Malmström, P.-U., Sjöberg, S. & Tolmachev, V. (2004). Radiobromination of anti-HER2/neu/ErbB-2 monoclonal antibody using the p-isothiocyanatobenzene derivative of the [76Br]undecahydro-bromo-7,8-dicarba-nido-undecaborate(1-) ion. Nuclear Medicine and Biology, 31(4), 425-33
Open this publication in new window or tab >>Radiobromination of anti-HER2/neu/ErbB-2 monoclonal antibody using the p-isothiocyanatobenzene derivative of the [76Br]undecahydro-bromo-7,8-dicarba-nido-undecaborate(1-) ion
Show others...
2004 (English)In: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 31, no 4, p. 425-33Article in journal (Refereed) Published
Abstract [en]

The monoclonal humanized anti-HER2 antibody trastuzumab was radiolabeled with the positron emitter (76)Br (T(1/2) =16.2 h). Indirect labeling was performed using the p-isothiocyanatobenzene derivative of the [(76)Br]undecahydro-bromo-7,8-dicarba-nido-undecaborate(1-) ((76)Br-NBI) as a precursor molecule. (76)Br-NBI was prepared by bromination of the 7-(p-isothiocyanato-phenyl)dodecahydro-7,8-dicarba-nido-undecaborate(1-) ion (NBI) with a yield of 93-95% using Chloramine-T (CAT) as an oxidant. Coupling of radiobrominated NBI to antibody was performed without intermediate purification, in an "one pot" reaction. An overall labeling yield of 55.7 +/- 4.8% (mean +/- maximum error) was achieved when 300 microg of antibody was labeled. The label was stable in vitro in physiological and denaturing conditions. In a cell binding test, trastuzumab remained immunoreactive after labeling.

Keywords
Antibodies; Monoclonal/*chemistry/immunology/*pharmacokinetics, Breast Neoplasms/immunology/*metabolism/radionuclide imaging, Bromine Radioisotopes/*chemistry/immunology/*pharmacokinetics, Cell Line; Tumor, Drug Stability, Humans, Isotope Labeling/*methods, Radioimmunodetection/methods, Radiopharmaceuticals/chemical synthesis/chemistry/pharmacokinetics, Receptor; erbB-2/immunology/*metabolism, Research Support; Non-U.S. Gov't
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-72941 (URN)10.1016/j.nucmedbio.2003.11.007 (DOI)15093812 (PubMedID)
Available from: 2005-06-21 Created: 2005-06-21 Last updated: 2017-12-14Bibliographically approved
Bruskin, A., Sivaev, I., Persson, M., Lundqvist, H., Carlsson, J., Sjöberg, S. & Tolmachev, V. (2004). Radiobromination of monoclonal antibody using potassium [76Br] (4 isothiocyanatobenzyl-ammonio)-bromo-decahydro-closo-dodecaborate (Bromo-DABI). Nuclear Medicine and Biology, 31(2), 205-11
Open this publication in new window or tab >>Radiobromination of monoclonal antibody using potassium [76Br] (4 isothiocyanatobenzyl-ammonio)-bromo-decahydro-closo-dodecaborate (Bromo-DABI)
Show others...
2004 (English)In: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 31, no 2, p. 205-11Article in journal (Refereed) Published
Abstract [en]

The use of charged linkers in attaching radiohalogens to tumor-seeking biomolecules may improve intracellular retention of the radioactive label after internalization and degradation of targeting proteins. Derivatives of polyhedral boron clusters, such as closo-dodecaborate (2-) anion, might be possible charged linkers. In this study, a bifunctional derivative of closo-dodecaborate, (4-isothiocyanatobenzyl-ammonio)-undecahydro-closo-dodecaborate (DABI) was labeled with positron-emitting nuclide (76)Br (T 1/2 = 16.2 h) and coupled to anti-HER2/neu humanized antibody Trastuzumab. The overall labeling yield at optimized conditions was 80.7 +/- 0.6%. The label was proven to be stable in vitro in physiological and a set of denaturing conditions. The labeled antibody retained its capacity to bind to HER-2/neu antigen expressing cells. The results of the study demonstrated feasibility for using derivatives of closo-dodecaborate in indirect labeling of antibodies for radioimmunoPET.

Keywords
Adenocarcinoma/*metabolism/*radionuclide imaging, Antibodies; Monoclonal/chemistry/*diagnostic use/*pharmacokinetics, Boron Compounds/chemical synthesis/*diagnostic use/*pharmacokinetics, Cell Line; Tumor, Drug Stability, Humans, Isotope Labeling/*methods, Metabolic Clearance Rate, Radiopharmaceuticals/chemical synthesis/diagnostic use/pharmacokinetics, Research Support; Non-U.S. Gov't
National Category
Organic Chemistry
Identifiers
urn:nbn:se:uu:diva-72891 (URN)15013486 (PubMedID)
Available from: 2005-06-21 Created: 2005-06-21 Last updated: 2017-12-14Bibliographically approved
Organisations

Search in DiVA

Show all publications