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1.
以3-甲基-2-丁烯酸为起始原料,经硅酯化和溴代后,再将(Z)-4-溴-3-甲基-2-丁烯酸硅酯转化成相应内酯,从而经蒸馏分离出其反式异构体(E)-4-溴-3-甲基-2-丁烯酸硅酯,水解后即生成(E)-4-溴-3-甲基-2-丁烯酸,总收率为29%.  相似文献   

2.
以丙酰乙酸乙酯为起始原料,先溴化得到4-溴丙酰乙酸乙酯,再在甲苯中与苯甲酰胺回流环合得到2-(5-甲基-2-苯基-4-(口恶)唑)-乙酸乙酯,最后经氢化铝锂还原,得到目标杂环中间体2-(5-甲基-2-苯基-4-(口恶)唑)-乙醇.该合成方法反应步骤少,原料便宜,目标物的总收率为67.3%.  相似文献   

3.
马来酸桂哌齐特的合成   总被引:1,自引:0,他引:1  
目的 改进马来酸桂哌齐特的合成方法。方法 以四氢吡咯为原料,与氯乙酰氯酰化得到中间体N-(2-氯乙酰基)四氢吡咯(1);以(E)-3,4,5-三甲氧基肉桂酸为原料,与特戊酰氯成混合酸酐后再与无水哌嗪进行单酰化反应制得中间体(E)-1-(3,4,5-三甲氧基)肉桂酰基哌嗪(2);中间体1与中间体2发生烃化反应制备桂哌齐特游离碱(3),3与马来酸成盐得目标化合物。结果与结论 以(E)-3,4,5-三甲氧基肉桂酸计,经3步反应合成了马来酸桂哌齐特,总收率为68.88%,其结构经1H-NMR、MS谱确证。  相似文献   

4.
Induction of cytosolic long-chain acyl-CoA hydrolases was investigated in rat liver after administration of various peroxisome proliferators and related compounds. Treatment of rats with di-(2-ethylhexyl)-phthalate, di-(2-ethylhexyl)-adipate or tiadenol induced hydrolases I and II, while acetylsalicylic acid induced only hydrolase II. Among the various phenoxyacetic acid derivatives and related compounds, 2,4,5-trichlorophenoxyacetic acid, 2-(4-chlorophenoxy)-2-methylacetic acid, 2-(2-chlorophenoxy)-2-methylpropionic acid and clofibric acid induced both hydrolases I and II, whereas 2, 4-dichlorophenoxyacetic acid induced only hydrolase II. All nine of the above-mentioned inducers also markedly increased the activity of peroxisomal beta-oxidation. Other compounds tested (2-chlorophenoxyacetic acid, 4-chlorophenoxyacetic acid, 4-chlorophenol, phenoxyacetic acid and phenoxy-2-methylacetic acid) were ineffective as inducers. These results suggest that inducers of acyl-CoA hydrolase II also enhance peroxisomal beta-oxidation activity, but do not necessarily induce acyl-CoA hydrolase I. The structure-inducing activity relationships of these compounds are discussed.  相似文献   

5.
Administration of 0.4% clofibrate in the diet stimulated estradiol (E(2))-induced mammary carcinogenesis in the August-Copenhagen Irish (ACI) rat without having an effect on serum levels of E(2). This treatment stimulated by several-fold the NAD(P)H-dependent oxidative metabolism of E(2) and oleyl-CoA-dependent esterification of E(2) to 17beta-oleyl-estradiol by liver microsomes. Glucuronidation of E(2) by microsomal glucuronosyltransferase was increased moderately. In contrast, the activity of NAD(P)H quinone reductase 1 (NQO1), a representative monofunctional phase 2 enzyme, was significantly decreased in liver cytosol of rats fed clofibrate. Decreases in hepatic NQO1 in livers of animals fed clofibrate were noted before the appearance of mammary tumors. E(2) was delivered in cholesterol pellets implanted in 7-8-week-old female ACI rats. The animals received AIN-76A diet containing 0.4% clofibrate for 6, 12 or 28 weeks. Control animals received AIN-76A diet. Dietary clofibrate increased the number and size of palpable mammary tumors but did not alter the histopathology of the E(2)-induced mammary adenocarcinomas. Collectively, these results suggest that the stimulatory effect of clofibrate on hepatic esterification of E(2) with fatty acids coupled with the inhibition of protective phase 2 enzymes, may in part, enhance E(2)-dependent mammary carcinogenesis in the ACI rat model.  相似文献   

6.
目的:合成2-羟基-5-[2-(4-(三氟甲基苯基)乙基氨基)]苯甲酸。方法:以对三氟甲基氯苯和5-氨基水杨酸为起始原料通过5步反应合成了细胞坏死抑制剂2-羟基-5-[2-(4-(三氟甲基苯基)乙基氨基)]苯甲酸。结果与结论:目标产物结构经1H-NMR,13C-NMR和ESI-MS确证,总产率为37.7%。该合成路线具有原料价廉易得、反应条件温和、收率高、操作简便的特点,适合于工业化生产。  相似文献   

7.
(RS)-2-Amino-3-(5-tert-butyl-3-hydroxy-4-isoxazolyl)propionic acid (ATPA), an analogue of (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA), has previously been shown to be a relatively weak AMPA receptor agonist and a very potent agonist at the GluR5 subtype of kainic acid-preferring (S)-glutamic acid ((S)-Glu) receptors. We report here the separation of (+)- and (−)-ATPA, obtained at high enantiomeric purity (enantiomeric excess values of 99.8% and >99.8%, respectively) using chiral chromatography, and the unequivocal assignment of the stereochemistry of (S)-(+)-ATPA and (R)-(−)-ATPA. (S)- and (R)-ATPA were characterized in receptor binding studies using rat brain membranes, and electrophysiologically using the rat cortical wedge preparation and cloned AMPA-preferring (GluR1, GluR3, and GluR4) and kainic acid-preferring (GluR5, GluR6, and GluR6+ KA2) receptors expressed in Xenopus oocytes. In the cortical wedge, (S)-ATPA showed AMPA receptor agonist effects (EC50=23 μM) approximately twice as potent as those of ATPA. (R)-ATPA antagonized depolarizations induced by AMPA (Ki=253 μM) and by (S)-ATPA (Ki=376 μM), and (R)-ATPA antagonized the biphasic depolarizing effects induced by kainic acid (Ki=301 μM and 1115 μM). At cloned AMPA receptors, (S)-ATPA showed agonist effects at GluR3 and GluR4 with EC50 values of approximately 8 μM and at GluR1 (EC50=22 μM), producing maximal steady state currents only 5.4–33% of those evoked by kainic acid. (R)-ATPA antagonized currents evoked by kainic acid at cloned AMPA receptor subtypes with Ki values of 33–75 μM. (S)-ATPA produced potent agonist effects at GluR5 (EC50=0.48 μM). Due to desensitization of GluR5 receptors, which could not be fully prevented by treatment with concanavalin A, (S)-ATPA-induced agonist effects were normalized to those of kainic acid. Under these circumstances, maximal currents produced by (S)-ATPA and kainic acid were not significantly different. (R)-ATPA did not attenuate currents produced by kainic acid at GluR5, and neither (S)- nor (R)-ATPA showed significant effects at GluR6. (S)-ATPA as well as AMPA showed weak agonist effects at heteromeric GluR6+KA2 receptors, whereas (R)-ATPA was inactive. Thus, (S)- and (R)-ATPA may be useful tools for mechanistic studies of ionotropic non-NMDA (S)-Glu receptors, and lead structures for the design of new subtype-selective ligands for such receptors.  相似文献   

8.
The possibility that arachidonic acid metabolism is involved in the secretory process in cultured adrenal chromaffin cells was investigated by studying the effects of lipoxygenase inhibitors and cyclooxygenase inhibitors on 45Ca2+ uptake and catecholamine release. Lipoxygenase inhibitors, which have different chemical structures, such as nordihydroguaiaretic acid (NDGA), 3-amino-1-(3-trifluoromethylphenyl)-2-pyrazoline (BW755C) and 2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone (AA861) all prevented the catecholamine release evoked by carbamylcholine and high K+. In contrast, cyclooxygenase inhibitors, such as aspirin and indomethacin failed to inhibit the carbamylcholine-evoked catecholamine release. Lipoxygenase inhibitors also inhibited 45Ca2+ uptake into the cells stimulated by carbamylcholine and high K+. Lipoxygenase inhibitors inhibited 45Ca2+ uptake and catecholamine release with similar potency. Slightly higher concentrations of lipoxygenase inhibitors were required to inhibit high K+-evoked effects compared to those evoked by carbamylcholine. The inhibitory effects of these inhibitors on carbamylcholine-evoked catecholamine release was different in its nature from the inhibitory effect of verapamil, a blocker of the Ca2+ channel, and was not due to a competitive antagonism at cholinergic receptor site. Moreover, these lipoxygenase inhibitors did not inhibit the binding of [3H]nitrendipine to chromaffin cell homogenate. The data suggest that lipoxygenase inhibitors prevent the catecholamine release from cultured adrenal chromaffin cells by blocking Ca2+ uptake. It might be possible that lipoxygenase product(s) is involved in the Ca2+ translocation system in these cells.  相似文献   

9.
2-甲基-2-羟基丙腈(2)经三甲基硅基(TMS)保护后,经Blaise反应并脱三甲基硅烷基保护,在亚硝酸钠和乙酸作用下肟化和Pd/C催化还原得到2-氨基-4-羟基-4-甲基-3-氧代戊酸乙酯三氟乙酸盐,再与丁酰亚氨酸甲酯盐酸盐环合得到奥美沙坦酯关键中间体4-(1-羟基-1-甲基乙基)-2-丙基-1H-咪唑-5-羧酸乙酯,总收率约40%。  相似文献   

10.
The in vitro interaction of four chlorophenoxyalkyl (CPA) acid herbicides with rat-liver glutathione S-transferase (GST) was studied using reduced glutathione and 1-chloro-2,4-dinitrobenzene as substrates. Inhibition of GST activity by the CPA acids in crude extracts was dose dependent. Ring substitution and side-chain length were shown to be of importance in determining the extent of GST inhibition. While GST AA, an isoenzyme of GST, was stimulated by two CPA acids, each of the other GST isoenzymes (A, B, C, E and M) was inhibited, to different degrees. Kinetic studies revealed a mixed type inhibition of the isoenzymes. Conjugates of CPA acids with glutathione were not formed. These results indicate that CPA acids interact with GST by binding directly to these proteins, possibly at a different locus from that of the substrate. The binding of CPA acids to GST may, therefore, have a protective function against these herbicides.  相似文献   

11.
(2E)-2-{6-[(E)-2-carboxylvinyl]-2,3-dihydroxyphenyl}-3-(3,4-dihydroxyphenyl) propenoic acid, a novel compound designated SMND-309, is a new metabolite of salvianolic acid B. The present study was carried out to investigate the effects of SMND-309 on experimental liver fibrosis in rats induced by subcutaneous injection of carbon tetrachloride and explore its possible mechanisms on the basis of biochemical, histopathologic and immunohistochemical studies. The results showed that intragastrical treatment with SMND-309 ameliorated liver function and decreased the elevation of serum hyaluronic acid, laminin, procollagen type III levels and hydroxyproline content in liver tissue. It also decreased the elevation in the malondialdehyde level and restored the decrease in superoxide dismutase and glutathione peroxidase activities. Upon histopathologic examination, the SMND-309-treated rats reduced the liver damage and the liver fibrosis grade. Moreover, the results of immunohistochemical examination showed that SMND-309 powerfully down-regulated the expression of connective tissue growth factor (CTGF) rather than transforming growth factor-beta1 (TGF-β1) in serum and liver. Meanwhile, SMND-309 exhibits significantly higher potency compared with salvianolic acid B (Sal B) at the same dose. The antifibrotic mechanisms of SMND-309 might be associated with its ability to suppress the expression of CTGF as well as scavenge lipid peroxidation products and increase endogenous antioxidant enzyme activity.  相似文献   

12.
2-(3-氰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯的合成   总被引:2,自引:0,他引:2  
目的优化非布司他关键中间体2-(3-氰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(4)的合成方法。方法采用"一勺烩"方法,以4-羟基苯甲腈为起始原料,首先与硫氢化钠和无水氯化镁在N,N-二甲基甲酰胺中反应,所得中间体不经分离,直接加入2-氯乙酰乙酸乙酯进行环合反应,得到2-(4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(2);然后通过六亚甲基四胺/三氟乙酸进行Duff反应,得到2-(3-甲酰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(3);再经盐酸羟胺/甲酸/甲酸钠体系脱水得到目标化合物。结果经四步反应合成非布司他关键中间体4,总收率为22.6%,其结构经核磁共振氢谱、质谱确证。结论改进后的工艺终产品无需柱色谱纯化,适合工业化生产。  相似文献   

13.
14.
G004, 1-(4-(2-(4-bromobenzenesulphonamino) ethyl) phenylsuphonyl)-3-(trans-4-methylcyclohexyl) urea, is being developed as a potential hypoglycaemic agent. In this study, the related compounds in the bulk drug substance of G004 were analyzed both qualitatively and quantitatively. An unknown compound in the drug, which has never been reported, was isolated using preparative liquid chromatography and characterized as 1-(4-(2-(2-bromobenzenesulphonamino) ethyl) phenylsuphonyl)-3-(trans-4-methylcyclohexyl) urea using nuclear magnetic resonance and mass spectrometry. Moreover, a reversed-phase liquid chromatography method was developed for quantification of both the major impurities and the main constituent. The proposed method was validated and applied during impurity studies and quality control analysis of the bulk drug and laboratory-prepared samples of G004.  相似文献   

15.
目的 设计合成2-甲基-5-(E)-(邻甲氧基苯亚甲基)环戊酮曼尼希碱类化合物,并对其抗炎活性进行初步评价。方法 以N-环戊烯基吗啉、邻甲氧基苯甲醛及多种胺类为原料,经多步反应全成目标化合物,并以二甲苯致小鼠耳肿胀模型测试目标化合物的抗炎活性。结果 共合成8个新化合物,经IR,^1H-NMR和MS确证其结构。其中两个化合物的抗炎活性与阿司匹林相当。结论 羧基a位被烷基取代的环戊酮曼尼希碱仍具有较强的抗炎作用。  相似文献   

16.
2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酰胺与2-巯基苯并噻唑为原料,哌啶为溶剂,在三乙胺催化下反应制得头孢菌素中间体2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酸S-苯并噻唑硫酯,收率约76%。  相似文献   

17.
对头孢布烯的关键中间体2-(2-苄氧羰基氨基噻唑-4-基)-5-(3-甲基-2-丁烯氧羰基)-2-戊烯酸(1)的合成工艺进行了研究。选用国内易得的(2-氨基噻唑-4-基)乙酸甲酯(2)作为起始原料,经过氨基保护、M ichae l加成-消除和选择性酯化三步反应制得目标化合物1,反应总收率63.0%。该工艺操作简单,生产成本低,适合工业化生产。  相似文献   

18.
Abstract

A new chromone and a new aliphatic ester were isolated from the EtOAc extract of myceliums of Daldinia eschscholtzii. Their structures were elucidated as (R)-5-hydroxy-8-methoxy-2-methylchroman-4-one (1) and (E)-6-(non-3-en-1-yl) -2H-pyran-2-one (2) by interpretation of the spectroscopic evidence.  相似文献   

19.
A novel sesquiterpene-substituted benzoic acid, named dictyvaric acid (1), together with nine known compounds (2-10), have been isolated from the brown alga Dictyopteris divaricata Okam. The structure of 1 was elucidated as 3-[(decahydro-2-hydroxy-2,5,5,8a-tetramethyl-1-naphthalenyl)-methyl]-4-hydroxybenzoic acid by spectroscopic methods, including IR, FABMS, HR-FABMS, 1D and 2D NMR techniques. All compounds were obtained from this species for the first time.  相似文献   

20.
目的建立HPLC法测定奥替溴铵含量和有关物质。方法色谱柱为Diamonsil ODS色谱柱(4.6 mm×200 mm,5μm);流动相:含3 mmo1.L-1庚烷磺酸钠的0.3 mo1.L-1三水合醋酸钠缓冲液乙腈甲醇(体积比为30∶70∶20)(乙酸调节pH值至6.0);流速:1.0 mL.min-1;检测波长:293 nm。结果在选定的色谱条件下,有关物质与主药分离良好,奥替溴铵在10.0~100.0 mg.L-1内质量浓度与峰面积呈良好的线性关系,r=0.999 7。结论方法可用于奥替溴铵含量测定及有关物质的检查。  相似文献   

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