共查询到20条相似文献,搜索用时 15 毫秒
1.
Yali Qiao Yong He Shuting Zhang Guixia Li Hang Liu Jingli Xu Xiao Wang Chuanmin Qi Cheng Peng 《Bioorganic & medicinal chemistry letters》2009,19(16):4873-4877
Two F-18 labeled fluoroarylvaline derivatives, methyl 2-(2-[18F]fluoro-4-nitrobenzamido)-3-methylbutanoate ([18F]1, [18F]MFNBMB) and its corresponding acid 2-(2-[18F]fluoro-4-nitrobenzamido)-3-methylbutanoic acid ([18F]2, [18F]FNBMBA), have been designed and synthesized, respectively, by our team. Meanwhile, we research on their biodistributions in mice model bearing S 180 tumor. Furthermore, we also carried out the biological evaluations of 2-[18F]fluorodeoxyglucose ([18F]FDG) and O-2-[18F]fluoroethyl-l-tyrosine (l-[18F]FET) in the same model for comparison with our targeting molecules [18F]1 and [18F]2. Excitingly, the tumor/blood (T/Bl) and tumor/brain (T/Br) ratios were 2.91, 7.06 at 30 min, 3.44, 5.61 at 60 min post injection for [18F]1, 2.32, 13.30 for [18F]2 at 30 min post injection, which were obviously superior to [18F]FDG and l-[18F]FET in the same model and demonstrated that [18F]1 and [18F]2, especially [18F]2, were potential PET imaging agents for tumor detection. 相似文献
2.
Xu J Liu H Li G He Y Ding R Wang X Feng M Zhang S Chen Y Li S Zhao M Qi C Dang Y 《Bioorganic & medicinal chemistry letters》2011,21(16):4736-4741
Two novel pyrazolo[1,5-a]pyrimidine derivatives, 7-(2-[18F]fluoroethylamino)-5-methylpyrazolo[1,5-a]pyrimidine-3-carbonitrile ([18F]FEMPPC, [18F]1) and N-(2-(3-cyano-5-methylpyrazolo[1,5-a]pyrimidin-7-ylamino)ethyl)-2-[18F]fluoro-4-nitrobenzamide ([18F]FCMPPN, [18F]2), have been designed and successively labeled with 18F by the nucleophilic substitution employing tosylate and nitryl as leaving groups, respectively. The radiochemical synthesis of both compounds was completed within 60 min with final high-performance liquid chromatography purification included. The corresponding radiochemical yields (without decay correction) were approximately 35% and 30%, respectively. Meanwhile, we compared the uptake characteristics of [18F]1 and [18F]2 with those of [18F]FDG and L-[18F]FET in S180 tumor cells. Furthermore, the tumor uptake of [18F]1 and [18F]2 was assessed in mice bearing S180 tumor and compared with [18F]FDG and L-[18F]FET in the same animal model. In vitro cell uptake studies showed [18F]1 had higher uptake than [18F]FDG, [18F]2 and L-[18F]FET over the 2 h period. In ex vivo biodistribution showed tumor/brain uptake ratios of [18F]2 were 12.35, 10.44, 8.69 and 5.13 at 15 min, 30 min, 60 min and 120 min post-injection, much higher than those of L-[18F]FET (2.43, 2.54, 2.93 and 2.95) and [18F]FDG (0.59, 0.61, 1.02 and 1.33) at the same time point. What’s more, the uptake of [18F]1 in tumor was 1.88, 4.37, 5.51, 2.95 and 2.88 at 5 min, 15 min, 30 min, 60 min and 120 min post-injection, respectively. There was a remarkable increasing trend before 30 min. The same trend was present for L-[18F]FET before 30 min and [18F]FDG before 60 min. Additionally, the tumor/brain uptake ratios of [18F]1 were superior to those of [18F]FDG at all the selected time points, the tumor/muscle and tumor/blood uptake ratios of [18F]1 at 30 min were higher than those of L-[18F]FET at the same time point. MicroPET image of [18F]1 administered into S180 tumor-bearing mouse acquired at 30 min post-injection illustrated that the uptake in S180 tumor was obvious. These results suggest that compound [18F]1 could be a new probe for PET tumor imaging. 相似文献
3.
Limin Wang Wenchao Qu Brian Lieberman Karl Ploessl Hank F. Kung 《Bioorganic & medicinal chemistry letters》2010,20(12):3482-3485
Three new 18F labeled fluoroalkyl tyrosine derivatives, O-(2-[18F]fluoroethyl)-α-methyltyrosine (FEMT, [18F]2), O-(2-[18F]fluoroethyl)-2-l-azatyrosine (FEAT, [18F]3), O-(2-[18F]fluoroethyl)-l-tyrosineamide (FETA, [18F]4) have been synthesized and radiofluorinated with 5–34% decay-corrected yield. In vitro studies were carried out in U-138 MG human glioblastoma. Cellular uptake of new tracers was compared to clinically utilized imaging agent O-(2-[18F]fluoroethyl)-l-tyrosine (FET, [18F]1). The uptake of tracers followed the order of FET ([18F]1) > FEAT([18F]3) > FEMT ([18F]2) ≈ FETA ([18F]4). 相似文献
4.
Qiao H Zhu L Lieberman BP Zha Z Plössl K Kung HF 《Bioorganic & medicinal chemistry letters》2012,22(13):4303-4306
A novel series of tropane derivatives containing a fluorinated tertiary amino or amide at the 2β position was synthesized, labeled with the positron-emitter fluorine-18 (t(1/2)=109.8 min), and tested as potential in vivo dopamine transporter (DAT) imaging agents. The corresponding chlorinated analogs were prepared and employed as precursors for radiolabeling leading to the fluorine-18-labeled derivatives via a one-step nucleophilic aliphatic substitution reaction. In vitro binding results showed that the 2β-amino compounds 6b, 6d and 7b displayed moderately high affinities to DAT (K(i)<10nM). Biodistribution studies of [(18)F]6b and [(18)F]6d showed that the brain uptakes in rats were low. This is likely due to their low lipophilicities. Further structural modifications of these tropane derivatives will be needed to improve their in vivo properties as DAT imaging agents. 相似文献
5.
Liu J Zhu L Plössl K Lieberman BP Kung HF 《Bioorganic & medicinal chemistry letters》2011,21(10):2962-2965
A series of novel N-fluoropyridyl-containing tropane derivatives were synthesized and their binding affinities for the dopamine transporter (DAT), serotonin transporter (SERT) and norepinephrine (NET) were determined via competitive radioligand binding assays. Among these derivatives, compound 6d showed the highest binding affinity to DAT (Ki = 4.1 nM), and selectivity for DAT over SERT (5-fold) and NET (16-fold). Compound 6d was radiolabeled with Fluorine-18 in two steps. Regional brain distribution and ex vivo autoradiography studies of [18F]6d demonstrated that the ligand was selectively localized in the striatum region, where DAT binding sites are highly expressed. [18F]6d may be useful as a potential radioligand for imaging DATs with PET. 相似文献
6.
Wang M Gao M Mock BH Miller KD Sledge GW Hutchins GD Zheng QH 《Bioorganic & medicinal chemistry》2006,14(24):8599-8607
Fluorinated 2-arylbenzothiazoles are new potential antitumor drugs, which show potent and selective inhibitory activity against breast, lung, and colon cancer cell lines. Carbon-11 labeled fluorinated 2-arylbenzothiazoles may serve as novel probes for positron emission tomography (PET) to image tyrosine kinase in cancers. The preparation of 4-fluorinated 2-arylbenzothiazoles 4-fluoro-2-(3-benzloxy-4-methoxyphenyl)benzothiazole (6a) and 4-fluoro-2-(3,4-dimethoxyphenyl)benzothiazole (6b) was achieved by a modification of Jacobson thioanilide radical cyclization chemistry. Hydrogenolytic cleavage of the benzyl ether group of compound 6a using H2/Pd–C provided the precursor 4-fluoro-2-(3-hydroxy-4-methoxyphenyl)benzothiazole (7) for radiolabeling. Synthesis of radiolabeling precursors and the reference standards 5- and 6-fluorinated arylbenzothiazoles (11c–n) was achieved via the reaction of o-aminothiophenol disulfides with substituted benzaldehydes under reducing conditions. The target radiotracers carbon-11 labeled 4-, 5-, and 6-fluorinated arylbenzothiazoles (3-[11C]6b, 4-[11C]11c, 3-[11C]11c, 5-[11C]11f, 4-[11C]11f, 4-[11C]11i, 3-[11C]11i, 5-[11C]11l, and 4-[11C]11l) were prepared by O-[11C]methylation of the phenolic hydroxyl precursors (7, 11d, 11e, 11g, 11h, 11j, 11k, 11m, and 11n) with [11C]methyl triflate and isolated by solid-phase extraction (SPE) purification in 30–55% radiochemical yields. 相似文献
7.
《Bioorganic & medicinal chemistry》2020,28(15):115577
c-MET-positive NSCLC is an important subtype accounting for about 5%~22% of lung cancer. NSCLC patients with activating c-MET are intensively sensitive to c-MET selective receptor tyrosine kinase (RTK) inhibitors, so we aimed to develop a specific PET probe targeting to c-MET-positive NSCLC for potential patients screened by PET/CT. Herein, PET tracer 18F-radiolabeled crizotinib derivative ([18F]FPC) was successfully achieved through a simple one-step 18F-labeling method. [18F]FPC PET imaging on c-MET-positive (as well as blocking group) and negative NSCLC models were further evaluated, and results showed that [18F]FPC was effective as a PET imaging probe that targeted c-MET-positive tumor. Therefore, [18F]FPC could be a potential PET imaging probe for NSCLC tumor which was sensitive to c-MET-TKIs. By virtue of this property, it will benefit NSCLC patients for c-MET-TKI treatment. 相似文献
8.
《Bioorganic & medicinal chemistry letters》2019,29(13):1620-1623
Orexin 1 receptor (OX1R) is thought to be involved in various body functions, including arousal maintenance and emotional control, but the full details of its function remain unknown. OX1R imaging with positron emission tomography (PET) would be useful in elucidating the orexin system including OX1R, but no PET probes targeting OX1R have been reported. We, therefore, designed and synthesized tetrahydroisoquinoline (THIQ) derivatives as novel PET probes targeting OX1R, and evaluated their utility. In an in vitro competitive binding assay, THIQ-1 and THIQ-2 showed significantly higher binding to OX1R (IC50 = 30 and 31 nM, respectively) than OX2R (IC50 = 160 and 332 nM, respectively). These features were also observed in a cell binding assay using [18F]THIQ-1 and [18F]THIQ-2, demonstrating their OX1R-specific binding property in vitro. In a biodistribution study using normal mice, the brain uptake of [18F]THIQ-1 was higher than that of [18F]THIQ-2, but further improvement is required for in vivo imaging with PET. Taken together, [18F]THIQ-1 and [18F]THIQ-2 have the potential to become useful imaging probes for PET targeting the OX1R, but require additional structural changes to improve their brain uptake. 相似文献
9.
Xia Wang Yan Li Winnie Deuther-Conrad Fang Xie Xin Chen Meng-Chao Cui Xiao-Jun Zhang Jin-Ming Zhang Jörg Steinbach Peter Brust Bo-Li Liu Hong-Mei Jia 《Bioorganic & medicinal chemistry》2013,21(1):215-222
We report the synthesis and evaluation of a series of fluoro-oligo-ethoxylated 4-benzylpiperazine derivatives as potential σ1 receptor ligands. In vitro competition binding assays showed that 1-(1,3-benzodioxol-5-ylmethyl)-4-(4-(2-fluoroethoxy)benzyl)piperazine (6) exhibits low nanomolar affinity for σ1 receptors (Ki = 1.85 ± 1.59 nM) and high subtype selectivity (σ2 receptor: Ki = 291 ± 111 nM; Kiσ2/Kiσ1 = 157). [18F]6 was prepared in 30–50% isolated radiochemical yield, with radiochemical purity of >99% by HPLC analysis after purification, via nucleophilic 18F? substitution of the corresponding tosylate precursor. The log DpH 7.4 value of [18F]6 was found to be 2.57 ± 0.10, which is within the range expected to give high brain uptake. Biodistribution studies in mice demonstrated relatively high concentration of radiotracers in organs known to contain σ1 receptors, including the brain, lungs, kidneys, heart, and spleen. Administration of haloperidol 5 min prior to injection of [18F]6 significantly reduced the concentration of radiotracers in the above-mentioned organs. The accumulation of radiotracers in the bone was quite low suggesting that [18F]6 is relatively stable to in vivo defluorination. The ex vivo autoradiography in rat brain showed high accumulation of radiotracers in the brain areas known to possess high expression of σ1 receptors. These findings suggest that [18F]6 is a suitable radiotracer for imaging σ1 receptors with PET in vivo. 相似文献
10.
Synthesis and evaluation of 18F-labeled dopamine D3 receptor ligands as potential PET imaging agents
Hocke C Prante O Löber S Hübner H Gmeiner P Kuwert T 《Bioorganic & medicinal chemistry letters》2005,15(21):4819-4823
A series of fluoro substituted aryl carboxamides was synthesized revealing high affinity for the dopamine D3 receptor. In contrast to 2-methoxy substitution, a 2,3-dichloro substitution pattern at the phenylpiperazine moiety induces a 10-fold increase of D3 affinity which is expressed by Ki values of 0.53, 1.1, and 9.0 nM for 8b, 8d, and 8f. Applying aromatic 18F-for-Br(Cl) substitution, high radiochemical yields between 76-82% were obtained for [18F]8c-f. The most promising ligand, [18F]8d, was used as imaging agent of the D3 receptor in vitro. However, due to the lack of specific binding, further studies should aim at the development of radioligands with improved D3 receptor selectivity. 相似文献
11.
Fang Liu Ziyou Huai Guotai Xia Liuping Song Sha Li Yulan Xu Kangjun Hong Mingyue Yao Gang Liu Yinjiu Huang 《Bioorganic & medicinal chemistry letters》2018,28(14):2561-2565
A series of 6,7,8-trimethoxy N-aryl-substituted-4-aminoquinazoline derivatives were synthesized as epidermal growth factor receptor (EGFR) inhibitors, and their antitumor activities were assessed in the gastric cancer cell line SGC7901 using MTT assay. All compounds of Tg1–14 were found to inhibit SGC7901 cell proliferation, and compound Tg11 (IC50?=?0.434?μM) was found to be slightly more effective against SGC7901 cells than epirubicin (IC50?=?5.16?μM). This suggests that compound Tg11 can be used as a new substitution structure to develop more efficacious antitumor agents. Western blot analysis showed that treatment with Tg11 (40?μM for 30?min) resulted in near complete inhibition of EGF-induced ERK1/2 phosphorylation, indicating that its anti-proliferative effect is largely associated with inhibition of ERK1/2 activation. These data imply that Tg11 is a potential anticancer agent capable of inhibiting cell proliferation. 相似文献
12.
Moon BS Lee TS Lee KC An GI Cheon GJ Lim SM Choi CW Chi DY Chun KS 《Bioorganic & medicinal chemistry letters》2007,17(1):200-204
We hereby report the synthesis of four fluorine-18 labeled tyrosine derivatives, 3-(2-[(18)F]fluoroethyl)tyrosine ([(18)F]1, [(18)F]ortho-FET), 3-(3-[(18)F]fluoropropyl)tyrosine ([(18)F]2, [(18)F]ortho-FPT) O-methyl-[3-(2-[(18)F]fluoroethyl)]tyrosine ([(18)F]3, [(18)F]MFET), and O-methyl-[3-(3-[(18)F]fluoropropyl)]tyrosine ([(18)F]4, [(18)F]MFPT). The fluorine-18 labeled tyrosine derivatives were prepared by the displacement reaction of the ethyl and propyl tosylates with K[(18)F]/K2.2.2 in acetonitrile under no-carrier-added (NCA) conditions, followed by hydrolysis with 4N HCl. The biological properties of labeled compounds were evaluated in rats bearing 9L tumor after an intravenous injection and PET image was obtained. The tumor/blood and tumor/brain ratios were 2.06, 2.92 for [(18)F]1, 2.25, 4.05 for [(18)F]2, 2.88, 1.90 for [(18)F]3, and 2.00, 2.60 for [(18)F]4 at 60 min post injection, respectively. The PET image showed localized accumulation of PET tracers in 9L glioma of the rat. 相似文献
13.
S. Nag G. Kettschau T. Heinrich A. Varrone L. Lehmann B. Gulyas A. Thiele É. Keller C. Halldin 《Bioorganic & medicinal chemistry》2013,21(1):186-195
The aim of this project was to synthesize and evaluate three novel fluorine-18 labeled derivatives of propargyl amine as potential PET radioligands to visualize monoamine oxidase B (MAO-B) activity.The three fluorinated derivatives of propargyl amine ((S)-1-fluoro-N,4-dimethyl-N-(prop-2-ynyl)-pent-4-en-2-amine (5), (S)-N-(1-fluoro-3-(furan-2-yl)propan-2-yl)-N-methylprop-2-yn-1-amine (10) and (S)-1-fluoro-N,4-dimethyl-N-(prop-2-ynyl)pentan-2-amine (15)) were synthesized in multi-step organic syntheses. IC50 values for inhibition were determined for compounds 5, 10 and 15 in order to determine their specificity for binding to MAO-B. Compound 5 inhibited MAO-B with an IC50 of 664 ± 48.08 nM. No further investigation was carried out with this compound. Compound 10 inhibited MAO-B with an IC50 of 208.5 ± 13.44 nM and compound 15 featured an IC50 of 131.5 ± 0.71 nM for its MAO-B inhibitory activity. None of the compounds inhibited MAO-A activity (IC50 > 2 μM).The fluorine-18 labeled analogues of the two higher binding affinity compounds (10 and 15) (S)-N-(1-[18F]fluoro-3-(furan-2-yl)propan-2-yl)-N-methylprop-2-yn-1-amine (16) and (S)-1-[18F]fluoro-N,4-dimethyl-N-(prop-2-ynyl)pentan-2-amine (18) were both prepared from the corresponding precursors 9A, 9B and 14A, 14B by a one-step fluorine-18 nucleophilic substitution reaction. Autoradiography experiments on human postmortem brain tissue sections were performed with 16 and 18. Only compound 18 demonstrated a high selectivity for MAO-B over MAO-A and was, therefore, chosen for further examination by PET in a cynomolgus monkey.The initial uptake of 18 in the monkey brain was 250% SUV at 4 min post injection. The highest uptake of radioactivity was observed in the striatum and thalamus, regions with high MAO-B activity, whereas lower levels of radioactivity were detected in the cortex and cerebellum. The percentage of unchanged radioligand 18 was 30% in plasma at 90 min post injection.In conclusion, compound 18 is a selective inhibitor of MAO-B in vitro and demonstrated a MAO-B specific binding pattern in vivo by PET in monkey. It can, therefore, be considered as a candidate for further investigation in human by PET. 相似文献
14.
《Bioorganic & medicinal chemistry letters》2020,30(12):127200
In the 21st century, the incidence and mortality of cancer, one of the most challenging diseases in the world, have rapidly increased. The purpose of this study was to develop 2-(2-[18F]fluoroethoxy)ethyl 4-methylbenzenesulfonate ([18F]FEM) as a positron emission tomography (PET) agent for tumor imaging. In this study, [18F]FEM was synthesized with a good radiochemical yield (45.4 ± 5.8%), high specific radioactivity (over 25 GBq/μmol), and commendable radiochemical purity (over 99%). The octanol/water partition coefficient of [18F]FEM was 1.44 ± 0.04. The probe demonstrated good stability in vitro (phosphate-buffered saline (PBS) and mouse serum (MS)), and binding specificity to five different tumor cell lines (A549, PC-3, HCC827, U87, and MDA-MB-231). PET imaging of tumor-bearing mice showed that [18F]FEM specifically accumulated at the tumor site of the five different tumor cell lines. The average tumor-to-muscle (T/M) ratio was over 2, and the maximum T/M values reached about 3.5. The biodistribution and dynamic PET imaging showed that most probes were metabolized by the liver, whereas a small part was metabolized by the kidney. Moreover, dynamic brain images and quantitative data showed [18F]FEM can quickly cross the blood brain barrier (BBB) and quickly fade out, thereby suggesting it may be a promising candidate probe for the imaging of brain tumors. The presented results demonstrated that [18F]FEM is a promising probe for tumor PET imaging. 相似文献
15.
Synthesis and biological evaluation of novel acylhydrazone derivatives as potential antitumor agents
We have designed, synthesized, and evaluated as potential antitumor agents a series of 2-hydroxybenzylidene derivatives of the N-(2-trifluoromethylpiridyn-4-yl)anthranilic acid hydrazide, and some analogues bearing a (2-trifluoromethyl)piridyn-4-ylamino group in 3- or 4-position of benzohydrazide or 4-position of phenylacetohydrazide. Compounds 12e, 13e, 15e, and 16e, bearing a 4-(diethylamino)salicylidene group exhibited potent cytotoxicity, with averaged GI50 values in sub-micromolar range, and a variety of cell selectivity at nanomolar concentrations. The determination of acute toxicity in athymic nudes mice proved some compounds to be non-toxic, making them good candidates for further study as antitumor agents. 相似文献
16.
Shubhashis Chakrabarty Michael S. Croft Melissa G. Marko Guillermo Moyna 《Bioorganic & medicinal chemistry》2013,21(5):1143-1149
We report the synthesis and evaluation as potential anticancer agents of a series of tetracyclic indenoquinolines. The compounds, which are obtained through the photoisomerization of Diels–Alder adducts formed between purpurogallin derivatives and nitrosobenzene, have in vitro antiproliferative activities in the μM to nM range against breast (MCF-7), lung epithelial (A-549), and cervical (HeLa) adenocarcinoma cells. The cytotoxicities of several of the novel tetracycles are comparable to or better than that of camptothecin. A strong correlation between the activity of the compounds and their aromaticity and planarity was observed, suggesting a mode of action similar to that of topoisomerase poisons. 相似文献
17.
Synthesis and bioactivities of 6,7,8-trimethoxy-N-aryl-4-aminoquinazoline derivatives 总被引:1,自引:0,他引:1
Liu G Hu DY Jin LH Song BA Yang S Liu PS Bhadury PS Ma Y Luo H Zhou X 《Bioorganic & medicinal chemistry》2007,15(20):6608-6617
A series of 4-aminoquinazoline derivatives is prepared by the nucleophilic substitution reaction of 6,7,8-trimethoxy-4-chloroquinazoline and aryl amine. The structures of the compounds are confirmed by elemental analysis, IR, and (1)H NMR spectral data. The compounds are also evaluated for their ability to inhibit tumor cells PC3, A431, Bcap-37, and BGC823 by MTT assays. Among them, 6b and 6e are found as potent inhibitors, with IC(50) values ranging from 5.8 to 9.8microM, in vitro assay. 相似文献
18.
《Bioorganic & medicinal chemistry letters》2014,24(7):1846-1850
Two novel small molecule gonadotropin-releasing hormone (GnRH) receptor antagonists (12 and 13) of the furamide-class were synthesized and evaluated in vitro for their receptor binding affinities for the rat GnRH receptor. Radiolabeling with no carrier added fluorine-18 of the appropriate precursors was investigated in a one-step reaction. Log P (Octanol/PBS pH 7.4) and serum stability of the compounds were investigated. The antagonists showed low nM affinity for the rat GnRH receptor. 18F-radiolabled compounds were obtained in high radiochemical purity (>95%) and specific activity (>75 GBq/μmol). These findings suggest this class of compounds holds promise as potential probes for PET targeting of GnRH-receptor expression. 相似文献
19.
Peng X Zhang A Kula NS Baldessarini RJ Neumeyer JL 《Bioorganic & medicinal chemistry letters》2004,14(22):5635-5639
A series of novel fluoroalkyl-containing tropane derivatives (6-8, 10-14, 17, and 18) were synthesized from cocaine. Novel compounds were evaluated for affinity and selectivity in competitive radioligand binding assays selective for cerebral serotonin (5-HT), dopamine (DA), and norepinephrine (NE) transporters (SERT, DAT, and NET). The nortropane-fluoroalkyl esters (7, 10, 11) were most potent for SERT (K(i): 0.18, 0.24, and 0.30 nM, respectively). Tosylate esters 17 and 18, synthesized as precursors for [(18)F]-labeled, Positron Emission Tomography (PET) imaging agents, also showed high affinity for DAT. 相似文献
20.
Yoann Joyard Vadim Le Joncour Hélène Castel Chérif Bounana Diouf Laurent Bischoff Cyril Papamicaël Vincent Levacher Pierre Vera Pierre Bohn 《Bioorganic & medicinal chemistry letters》2013,23(13):3704-3708
Tumor hypoxia plays a major role in reducing the efficacy of therapeutic modalities like chemotherapy and radiation therapy in combating cancer. In order to target hypoxic tissues, a tripeptide ligand having a 2-nitroimidazole moiety, as a bioreductive species, was synthesized. The latter was radiolabeled with 99mTc for imaging hypoxic regions of tumors and was characterized by means of its rhenium analogue. The biodistribution and scintigraphic image of the corresponding 99mTc-complex showed accumulation in tumor and these results suggest that it could be a marker for imaging tumor hypoxia. 相似文献