摘要:

AbstractThe preparation and synthesis of [125I]7α‐O‐iodoallyl diprenorphine, a high affinity opioid receptor antagonist, is described using a versatile vinylstannane as prosthetic group for radioiodination at the tertiary alcohol group in the 7α‐side chain. Radioiododestannylation with selective conditions in one step occurs under mild, no‐carrier‐added‐conditions to give the corresponding [125I]7α‐O‐iodoallyl diprenorphine analogue in good radiolabelled yields (70‐90%) with specific radioactivity 80 TBq/mmol (2200 Ci/mmol) and radiochemical purity>95%. Iodoallyl diprenorphine exhibitedin vitroa very high affinity (Ki= 0.4 nM), so that this radioligand could be suitable for imaging opioid receptors in living humans by Single Photon Emission Compute

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360702

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

Abstract(−)‐[11C]Phenylephrine and positron emission tomography could potentially be used to assess neuronal monoamine oxidase activity in the heart. Previous data for (−)‐(11C]phenylephrine indicate that, although its retention and neuronal selectivity parallel that of the neuronal mapping agent (−)‐[11C]hydroxyephedrine, its neuronal storage and clearance properties are quite different. In order to study thein vivokinetics of (−)‐[11C]phenylephrine in greater detail, the dideutero analog [11C]‐(−)‐α,α‐dideutero‐phenylephrine,1, was synthesized by [11C]methylation of the precursor (−)‐α,α‐dideutero‐m‐octopamine. The key step in the procedure was BD3reduction of the cyanohydrin derived from 3‐hydroxybenzaldehyde. Deuterium incorporation at the alpha positions ofm‐octopamine was confirmed by NMR and mass spectroscopy of the deuterated product and by comparison of spectral data with undeuteratedm‐octopamine. (−)‐α,α‐Dideutero‐m‐octopamine was methylated with CF

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360703

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

Abstract2′‐Deoxy[Amino‐15N]Adenosine has been constructed in two steps from commercially available starting materials. These reactions have been scaled up to give 5 gram lots of labeled mat

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360704

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractCarbonation of the aryl lithium obtained from p‐N,N(dimethylamino)bromobenzene with carbon‐14 labeled carbon dioxide, followed by esterification gave [CO2‐14C]p‐N,N(dimethylamino)benzoate 2‐ethylhexyl ester (Padimate‐O). This material underwent slow decomposition to [14C]N‐nor‐Padimate‐O and [14C]N‐formyl‐N‐nor‐Padimate‐O. Nitrosation of [14C]Padimate‐O with sodium nitrite afforded [1

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360705

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractSynthesis of two tritiated 1α,25‐dihydroxy‐22‐oxavitamin D3(OCT), [26‐3H3]OCT (3) and [2β‐3H]OCT (4), is described. [26‐3H3]OCT (3) was prepared by tritiation at the side chain with tritiated methylmagnesium iodide and [2β‐3H]OCT (4) was labeled at the A‐ring by tritiation with s

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360706

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractIncorporation of a double13C label into the mustard 2‐chloroethyl phenyl sulfide2is straightforward, but analysis is complicated by13C‐13C coupling. An alternative is reported, in which the ease of scrambling of sulfur mustards is used to advantage to prepare precisely 50% (1, 2‐13C) enriched2, with each carbon of the ethyl chain labelled to provide optimal signal to noise in the13C spe

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360707

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractReaction ofN‐(trimethylsilyl)imidazole (2) with phosgene‐14Cin toluene afforded 92 w/w % pure (1H NMR) 1,1′‐carbonyldimidazole‐1‐14C(3) in near quantitative yield. Activation of MPEG‐amine4by reaction with3in dichloromethane afforded intermediate5in situ. Further reaction with hydrazine in toluene at 50°C and reprecipitation from 2‐propanol afforded crude1(81%). A two‐step chromatographic purification of this material followed by reprecipitation from 2‐propanol gave MPEG‐semicarbazide linker1. This material had a chemical purity estimated at 98%, a radiochemical purity of 95%, a specific activity of 7.7 μCi/mg (37.6 mCi/mmol) and a number‐average molecula

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360708

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractUsing sodium acetate, [1‐14C] as a starting material, a total of seven steps were required to synthesize the title compound. This involved acylation of ortho‐dichlorobenzene to form dichloroacetophenone, [2‐14C] (I). The 2‐phenyl‐4‐quinoline carboxylic acid, [2‐14C] (II) was prepared by the Pfitzinger reaction from (I) and dichloroisatin. Compound II was converted to the acid chloride (III) by reaction with SOCl2in benzene. Grignard condensation reaction of (III) yielded 4‐quinolylmethylketone, [2‐14C] (IV) which was then converted to the bromomethylketone (V). Compound V was reacted with NaBH4to form the ethylene oxide (VI). Alkylation of the oxide yielded the title compound (VII). The overall radiochemical yield was 10.1% and the specific activity was 3.0 mCi/mmol, with a radiochemica

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360709

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractA convenient method to synthesize radiolabelled glucose‐1,6‐bisphosphate (Glc‐1,6‐P2) of high specific activity and in a high yield is reported. The method is based on enzymatic formation of glucose‐6‐P from glucose and ATP using hexokinase. The labelled glucose‐6‐P is then converted to Glc‐1,6‐P2through an equilibrium reaction catalyzed by phosphoglucomutase. The two enzymatic steps and TLC separations necessary to afford radiochemically pure Glc‐1,6‐P2can be completed in one day. The outlined experimental procedure details the synthesis of [33P]Glc‐1,6‐P2evenly labelled at the carbon 1 and the carbon 6 position. However the commercial availability of γ‐33P and γ‐32P labelled ATP and of glucose labelled with3H,14C and13C provides the option to label glucose‐1,6‐bi

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360710

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractIn order to improve the scintigraphy and radiotherapy of neuroendocrine tumors we synthesized two radioiodinated benzylamines [N‐(2‐chloroethyl)‐N‐ethyl‐2‐[125I]iodobenzylamine and N,N‐diethyl‐2‐[125I]iodobenzylamine], analogs of xylamine [N‐(2‐chloroethyl)‐N‐ethyl‐2‐methylbenzylamine]. Xylamine is an irreversible inhibitor of uptake and accumulation of noradrenaline. The two unlabelled iodinated derivatives [N‐(2‐chloroethyl)‐N‐ethyl‐2‐iodobenzylamine and N,N‐diethyl‐2‐iodobenzylamine]were synthesized, purified and checked by HPLC, NMR and mass spectrography. Their affinity for the noradrenaline transporter was determinedin vitroon rat brain membrane homogenates with [3H]nisoxetine. Radioiodination was performed by iodide for bromide nucleophilic exchange from brominated precursors. The N,N‐diethyl‐2‐[125I]iodobenzylamine was obtained directly from N,N‐diethyl‐2‐bromobenzylamine. Radiosynthesis of N‐(2‐chloroethyl)‐N‐ethyl‐2‐[125I]iodobenzylamine required three steps. A new brominated precursor [N‐ethyl‐N‐(2‐bromobenzyl)glycine ethyl ester]which was stable for radiolabelling and suitable for reduction to N‐(2‐hydroxyethyl)‐N‐cthyl‐2‐[125I]iodobenzylamine was synthesized. N‐(2‐Hydroxyethyl)‐N‐ethyl‐2‐[125I]iodobenzylamine was converted to N‐(2‐chloroethyl)‐N‐ethyl‐2‐[125I]iodobenzyla

ISSN:0362-4803    

DOI:10.1002/jlcr.2580360711

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY