摘要:

AbstractTen aryl‐carbohydrate ligands have been synthesized that potentially increase the tumor retention and decrease the deiodination of iodinated monoclonal antibodies used in the imaging and treatment of cancer. The compounds were synthesized via reductive amination reactions, purified with cation exchange chromatography, and characterized using1H and13C NMR. These compounds were then radioiodinated to assess their iodination characteristics, for subsequent experiments involving attachment to monoclonal antibodie

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280502

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe oxidation state of technetium‐pyrophosphate (99m‐Tc PYP) reduced by SnCl2.2H2O was determined by radiochromatography. Two different complexes were formed (complex I and complex II). The oxidation states of Tc to be III or IV or both in complex II or hydrated technetium dioxide in complex I were investigated. Formation of Tc (III)/Tc(IV)‐PYP and hydrated technetium dioxide‐PYP complexes were studied by radiochromatography and by biodistribution in mice. Experiments in animals helped to clarify the behaviour of these complexes. Thus urine obtained from one group of mice injected with 99m‐Tc‐PYP complexes wase reinjected to another group of mice. It was found that complex II excreted in the urine was not broken down while cleavage and deposition of 99m‐Tc‐species were found with complex I ex

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280503

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractA method is reported for the preparation of lyophilized MAA kits for99mTc labelling in a single step process. High radiochemical yield was obtained. Lung and liver uptake in mice were determined to be 97% and 0.2% respectively.

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280504

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractRetinyl acetate (4a) has been prepared with a tritium label at the C‐11 and C‐12 positions by partial reduction of oxenin (1) with tritium gas followed by acetylation and rearrangement. Specific activities of up to 40 curies/mmole have been attained. By alkaline hydrolysis, retinol (5) has been obtained and derivatized as one of several retinyl esters or has been oxidized to all‐transretinoic acid (6) having equally high specific tritium activities. From beta ionone (12), 13‐cisretinoic acid (10) has been elaborated in a variety of isotopically labeled forms. A key reaction in the sequence, the Wittig coupling of the triphenylphosphonium derivative of vinyl beta ionol (15a‐c) and the butenolide, 5‐hydroxy‐4‐methyl‐2(5H)‐furanone (8), provides access to 13‐cisretinoic acid and its 4‐oxo metabolite labeled with either isot

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280505

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractSeven‐membered ring compounds, from cylcoheptane to complex ring structures containing heteroatoms, substituents and fused phenyl rings, were labeled with tritium, using activated and adsorbed tritium. The 7‐membered ring structures are generally stable towards reactions with tritium, which allows compounds like 1‐benzosuberone, 1‐aza‐2‐methoxy‐1‐cycloheptene, iminostilbene and clozapine to be labeled to reasonably high specific activities. The best method varies greatly from compound to compound. By optimizing the labeling conditions and use of efficient support exceptionally good results can be obtained. The Pd‐on‐alumina support gives consistently higher specific activity and less radioimpurity than other supports. Even molecules containing carbon‐halogen bond and hydrogen bound to nitrogen can usually be labeled with tritium at stable positions and w

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280506

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractMethylprednisolone suleptanate was initially labeled with tritium in the A‐ring of the steroid portion of the molecule, and with carbon‐14 at both carboxylic carbons of the suberic acid portion of the side chain. However these labels proved to lack total metabolic stability after administration to rats. Subsequently a second pair of labeled methylprednisolone suleptanates was synthesized, with tritium at C‐7 in the B‐ring of the steroid and carbon‐14 exclusively at the carboxamide carbon in the side chain. These labeled compounds showed excellent metabolic stability of both the tritium and carbon‐14 labels, and should be well suited for conducting drug disposit

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280507

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe synthesis of 2‐amino‐3‐([15N]‐methylamino)propanoic acid (synonyms, BMAA, β‐N‐methylamino‐alanine) from α‐acetamidoacrylic acid and [15N]‐methylamine is described. Enantioselective hydrolysis of the acetamide group, mediated by the enzyme Acylase 1 (EC 3.5.1.14), yielded (R)‐BMAA and the (S)‐α‐acetamido derivative. Acid hydrolysis of the latter

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280508

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractNew synthetic routes were developed for incorporating13C into the oxazaphosphorine ring and nitrogen mustard functionality of cyclophosphamide metabolites. 1,2‐13C2‐Vinylbromide and ethylene oxide were used to synthesize 3,4‐13C2‐3‐butenylN,N‐bis(2‐chloroethyl)phosphorodiamidate via the intermediacy of 3,4‐13C2‐3‐buten‐1‐ol. Ozonolysis of the phosphorodiamidate gave 4‐13C‐4‐hydroperoxycyclophosphamide with an overall yield of 16% which was 27‐times higher than a previously reported synthesis. As an extension of this synthetic pathway, 2‐13C‐ethyl bromoacetate was used to incorporate13C into the C1position of bis(2‐chloroethyl)amine hydrochloride which was used as a precursor to alpha‐13C‐4‐hydroperoxycyclophosphamide (obtained in 16% overall yield). Also discussed are applications of these pathways to the synthesis of diversely labelled (14C,13C,2H) 4‐hydroperoxycyclophosphamides, chirally‐labelled oxazaphosphorines, phosph

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280509

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe synthesis of [14C] labelled Sulodexide is reported. Sulodexide is a sulphated polysaccharide of the class of glycosaminoglycan, containing a heparin like fraction (70%), dermatan sulphate (20%) and other minor fractions. The heparin‐like fraction, suitably isolated from other components, was partially and selectively N‐desulphated, thus making few percent unit ‐NH2groups available for the labelling with [14C]‐acetic anhydride (specific activity 0.15 μCi/mg). Due to the small extent of modification, the sulphate to carboxylate group ratio remained practically unchanged on the heparin‐like fraction. Sulodexide was reconstituted adding to the labelled fraction the suitable amount of the other components; the chemical and biological properties of the final labelled Sulodexide were undistinguishable from those of the startin

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280510

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe synthesis of a tosylate precursor for the radiosynthesis of a potential PET radiotracer, (S)‐N‐[(1‐ethyl‐2‐pyrrolidinyl)methyl]‐5‐(2‐[18F]fluoroethyl)‐2‐ methoxybenzamide is reported. Reaction of18F‐fluoride with the tosylate provides the radiolabeled product in 10–25% yield. Specific activity of the radiotracer varied between 600–800 Ci/mmol after purification of the product mixt

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280511

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY