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1.
以丁酮为原料,与由亚磷酸三乙酯和氯乙酸乙酯反应得到的二乙氧基磷酰基乙酸乙酯进行Wittig-Horner反应后,再经碱性水解、溴加成反应和脱溴脱羧反应制得(z)-1-溴-2-甲基-1-丁烯,总收率53.2%(以丁酮计). 相似文献
2.
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
3.
4.
目的合成3-(3-羟基-1-甲基丙氧基)-1.丁醇(Ⅰ)和3-(3-羟基丁氧基)-1-丁醇(Ⅰ),并改进工艺提高产品纯度。方法以1,3-丁二醇为起始原料,通过硫酸催化双分子缩合、三苯甲基选择性保护、分离提纯、脱保护基4步反应得到目标化合物。结果与结论化合物Ⅰ的结构经。H.NMR13C-NMR谱确证,其含量经C-C测定,大于99.5%。化合物Ⅰ的纯度为90.0%,与文献相比纯度都有相应提高。 相似文献
5.
2,6,6-三甲基-1-环己烯-1-甲醛与(3-甲氧基-2-甲基烯丙基)膦酸二乙酯经Wittig-Homer缩合制得1-甲氧基-2-甲基-4-(2,6,6-三甲基-1-环己烯-1-基)-1,3-丁二烯,然后经酸催化水解得到维生素A的关键中间体2-甲基-4-(2,6,6-三甲基-1-环己烯-1-基)-2-丁烯醛,总收率约47%. 相似文献
6.
研究1-烷基-5-氨基-6-苯乙基尿嘧啶(1a,1b)方便、高产率的合成方法,此类化合物有可能作为非核苷类HIV-1RT抑制剂。以6-甲基尿嘧啶(2)为起始物,经硝化、烷基化、苄基化及一锅反应脱苄基及还原反应等合成目标化合物,并用NMR、MS、IR、Anal鉴定化合物结构。探索出了一种合成1-烷基-5氨基-6-苯乙基尿嘧啶类化合物的方便方法。首次于用3或4步反应、高产率合成了1-烷基-5-氨基-6-苯乙基尿嘧啶(1a,1b)并发现化合物1a有中度抗HIV-1RT的活性(IC50=29μM)。 相似文献
7.
目的从海洋真菌的代谢产物中寻找新的具有抗真菌活性的化合物。方法以稻瘟霉生物模型筛选海洋真菌,获得编号09-1-1-1的活性菌株,从其发酵液中分离活性代谢产物。结果从发酵液中分离到2个化合物,鉴定其结构为3a,12c-二氢-8-羟基-6-甲氧基-7H-呋喃[3′,2′∶4,5]呋喃[2,3-c]呫吨-7-酮(Ⅰ,sterig-matocystin)和1,3,6,8-四羟基-2-(1-羟己基)-9,10-蒽二酮(Ⅱ,averantin)。结论稻瘟霉生物模型用于筛选海洋真菌活性代谢产物成本低、快速又方便。化合物Ⅱ对109稻瘟霉菌丝的生长最小抑制浓度为1.6μg.mL-1。 相似文献
8.
以邻苯二胺为起始原料,经过缩合、氯代、烷基化和取代反应来合成4-[[1-[(4-氟苯基)甲基]-1H-2-苯并咪唑基]氨基]-1-哌啶甲酸乙酯。该合成方法操作简单,总收率达到30.7%。 相似文献
9.
目的对4-羟基-2-(1H-吡唑-1-基)嘧啶-5-甲酸的合成工艺条件进行优化。方法以1-脒基吡唑盐酸盐和乙氧基甲叉基丙二酸二乙酯为起始原料,在三乙胺催化下环合得到中间体4-羟基-2-(1H-吡唑-1-基)嘧啶-5-甲酸乙酯,再经过氢氧化锂在四氢呋喃–水混合溶剂中水解得到目标化合物。结果合成了目标化合物,经MS、1H-NMR确证了结构,质量分数为99.5%,本合成工艺的总收率为87%。结论该合成工艺具有操作简单、反应条件温和、成本低、产率和纯度较高等优点,适合工业化生产。 相似文献
10.
目的:建立测定1-氟萘中1-萘胺杂质的HPLC方法。方法:采用Agilent 1200色谱系统,色谱柱为Agilent XDB C18柱(250mm×4.6mm,5μm);流动相为碳酸氢铵缓冲液(用磷酸调节pH值为6.0)∶乙腈=32∶68,等度洗脱;流速1.0ml/min,柱温30℃;检测波长为220nm。结果:1-萘胺在0.013~1.53μg/ml浓度范围内具有良好的线性关系,线性相关系数(r)为1.0,平均加样回收率为99.92%。结论:该方法简单、快速、准确和重复性好,可用于1-氟萘中1-萘胺杂质含量的控制。 相似文献
11.
M. Miksits A. Maier-Salamon S. Aust T. Thalhammer G. Reznicek O. Kunert 《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(12):1101-1119
Sulfation of resveratrol, a polyphenolic compound present in grapes and wine with anticancer and cardioprotective activities, was studied in human liver cytosol. In the presence of 3′-phosphoadenosine-5′-phosphosulfate, three metabolites (M1–3) whose structures were identified by mass spectrometry and NMR as trans-resveratrol-3-O-sulfate, trans-resveratrol-4′-O-sulfate, and trans-resveratrol-3-O-4′-O-disulfate, respectively. The kinetics of M1 formation in human liver cytosol exhibited an pattern of substrate inhibition with a Ki of 21.3?±?8.73?µM and a Vmax/Km of 1.63?±?0.41?µL?min?1mg?1 protein. Formation of M2 and M3 showed sigmoidal kinetics with about 56-fold higher Vmax/Km values for M3 than for M2 (2.23?±?0.14 and 0.04?±?0.01?µL?min?1?mg?1). Incubation in the presence of human recombinant sulfotransferases (SULTs) demonstrated that M1 is almost exclusively catalysed by SULT1A1 and only to a minor extent by SULT 1A2, 1A3 and 1E1, whereas M2 is selectively formed by SULT1A2. M3 is mainly catalysed by SULT1A2 and 1A3. In conclusion, the results elucidate the enzymatic pathways of resveratrol in human liver, which must be considered in humans following oral uptake of dietary resveratrol. 相似文献
12.
Dávila-Borja VM Belmont JA Espinosa JJ Moreno-Sánchez R Albores A Montero RD 《Archives of toxicology》2007,81(10):697-709
Histamine (HA) may bind to cytochrome P450 (CYP450) in rat liver microsomes. The CYP450-HA complex seems to regulate some cellular processes such as proliferation. In the present work, it is shown that HA increases the activity and protein level of CYP1A1 and CYP2E1, in vivo. CYP1A1 is associated with polycyclic aromatic hydrocarbon-mediated carcinogenesis and CYP2E1 with liver damage by oxidative stress. Studies of enzyme kinetics and binding with rat liver microsomes and supersomes were carried out to determine whether HA is a substrate of CYP1A1 and/or CYP2E1. The lack of NADPH oxidation in the presence of HA showed that it is not a substrate for CYP1A1. Activity measurements using the O-dealkylation of ethoxyresorufin indicated that HA is a mixed-type inhibitor of CYP1A1 in both microsomes and supersomes. On the other hand, HA induced a significant NADPH oxidation catalyzed by CYP2E1 supersomes, strongly suggesting that HA is a substrate for this isoform. Furthermore, HA is consumed in the presence of CYP2E1-induced microsomes and supersomes, as determined by o-phtalaldehyde complexes with HA by HPLC. The present findings may contribute to understand better the physiological function of CYP450 in relation with inflammation and other physiological processes in which HA may have a relevant role. 相似文献
13.
Young-Jin Chun Young-Kun Oh Beom Joon Kim Donghak Kim Sung Su Kim Hyung-Kyoon Choi Mie-Young Kim 《Toxicology letters》2009
Human cytochrome P450 1B1 (CYP1B1) is found mainly in extrahepatic tissues and is overexpressed in a variety of human tumors. Metabolic activation of 17β-estradiol (E2) to 4-hydroxy E2 by CYP1B1 has been postulated to be an important factor in mammary carcinogenesis. The inhibition of recombinant human CYP1B1 by 2,2′,4,6′-tetramethoxystilbene (TMS) was investigated using either the Escherichia coli membranes of recombinant human CYP1B1 coexpressed with human NADPH-P450 reductase or using purified enzyme. 2,2′,4,6′-TMS showed potent and selective inhibition of ethoxyresorufin O-deethylation (EROD) activity of CYP1B1 with IC50 values of 2 nM. 2,2′,4,6′-TMS exhibited 175-fold selectivity for CYP1B1 over CYP1A1 (IC50, 350 nM) and 85-fold selectivity for CYP1B1 over CYP1A2 (IC50, 170 nM). However, inhibition of human NADPH-P450 reductase activity by 2,2′,4,6′-TMS was negligible. The modes of inhibition by 2,2′,4,6′-TMS were noncompetitive for CYP1A1 and CYP1B1. Moreover, 2,2′,4,6′-TMS significantly suppressed EROD activity and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced CYP1A1 or CYP1B1 gene expression in human tumor cells such as HepG2 and MCF-10A. Taken together, our results indicate that 2,2′,4,6′-TMS is a potently selective inhibitor of human CYP1B1 as well as a suppressor of CYP1B1 expression and may be a valuable tool for determining enzyme properties of human CYP1B1. 相似文献
14.
Effect of TCDD exposure on CYP1A1 and CYP1B1 expression in explant cultures of human endometrium. 总被引:8,自引:0,他引:8
D P Bofinger L Feng L H Chi J Love F D Stephen T R Sutter K G Osteen T G Costich R E Batt S T Koury J R Olson 《Toxicological sciences》2001,62(2):299-314
Endometriosis is a debilitating disease estimated to affect 10% of reproductive-age women and characterized by the growth of endometrial tissue outside of the uterus. The present study characterizes a human endometrial explant culture model for studying the direct effects of TCDD exposure by assessing the expression of CYP1A1 and CYP1B1 mRNA (Northern blotting), protein (Western blotting), and activity (7-ethoxyresorufin-O-deethylase; EROD) in explants cultured with and without TCDD. Explants were obtained at laparoscopy or laparotomy from women undergoing surgery for tubal ligation, endometriosis, or pelvic pain unrelated to endometriosis. The explants were cultured with 10 nM estradiol (E(2)) or 1 nM E(2) plus 500 nM progesterone (P(4)) with or without TCDD (first 24 h). The expression of CYP1A1 and CYP1B1 mRNA was greatest with 10 nM TCDD and increased up to 72 h after initial exposure. EROD activity increased up to 120 h. Explants from a secretory phase biopsy became reorganized in culture and formed a new epithelial membrane, while maintaining basic endometrial morphology and viability for up to 120 h. At 24 h, TCDD significantly increased CYP1A1 and CYP1B1 mRNA, and at 72 h, TCDD significantly increased EROD activity and CYP1B1 protein compared to explants cultured without TCDD for similar times. CYP1B1 protein also exhibited substantial constitutive expression that was similar in uncultured biopsies, where CYP1B1 protein was immunolocalized in the cytoplasm of epithelial glands, with only occasional patches of protein in the surface epithelial membrane. In explants cultured with and without TCDD exposure, CYP1B1 protein was localized in the cytoplasm of the new surface epithelial membrane and glands closest to the surface. CYP1A1 protein was not detected in uncultured biopsies or explants. Both younger age (age 30 and under) and proliferative phase were associated with higher TCDD-induced EROD activity in specimens treated with E(2):P(4). No significant endometriosis-related differences were observed for any of the biomarkers, but the detection of disease-specific change was limited by small sample size and variability in tissue-cycle phase. The human endometrial explant culture model will be useful for future studies of the effects of dioxin-like compounds on human endometrium in relationship to cycle phase and hormonal exposure. 相似文献
15.
目的合成1,1,2-三甲基-1H-苯并[e]吲哚。方法由2-萘胺经重氮化反应、还原反应制得2-萘肼,再与甲基异丙基酮经费歇尔吲哚合成反应制得目标化合物。结果与结论经熔点测定及1H-NMR分析确证目标化合物结构,总收率为26.4%。 相似文献
16.
Oxidation of pyrene, 1-hydroxypyrene, 1-nitropyrene and 1-acetylpyrene by human cytochrome P450 2A13
Tsutomu Shimada Norie Murayama Valerie M. Kramlinger Joo-Hwan Kim Donghak Kim 《Xenobiotica; the fate of foreign compounds in biological systems》2016,46(3):211-224
Abstract1.?The polycyclic hydrocarbons (PAHs), pyrene, 1-hydroxypyrene, 1-nitropyrene and 1-acetylpyrene, were found to induce Type I binding spectra with human cytochrome P450 (P450) 2A13 and were converted to various mono- and di-oxygenated products by this enzyme.2.?Pyrene was first oxidized by P450 2A13 to 1-hydroxypyrene which was further oxidized to di-oxygenated products, i.e. 1,8- and 1,6-dihydroxypyrene. Of five other human P450s examined, P450 1B1 catalyzed pyrene oxidation to 1-hydroxypyrene at a similar rate to P450 2A13 but was less efficient in forming dihydroxypyrenes. P450 2A6, a related human P450 enzyme, which did not show any spectral changes with these four PAHs, showed lower activities in oxidation of these compounds than P450 2A13.3.?1-Nitropyrene and 1-acetylpyrene were also found to be efficiently oxidized by P450 2A13 to several oxygenated products, based on mass spectrometry analysis.4.?Molecular docking analysis supported preferred orientations of pyrene and its derivatives in the active site of P450 2A13, with lower interaction energies (U values) than observed for P450 2A6 and that several amino acid residues (including Ala-301, Asn-297 and Ala-117) play important roles in directing the orientation of these PAHs in the P450 2A13 active site. In addition, Phe-231 and Gly-329 were found to interact with pyrene to orient this compound in the active site of P450 1B1.5.?These results suggest that P450 2A13 is one of the important enzymes that oxidizes these PAH compounds and may determine how these chemicals are detoxicated and bioactivated in humans. 相似文献
17.
Carmen Galán Natalia Dionisio Tarik Smani Ginés M. Salido Juan A. Rosado 《Biochemical pharmacology》2011,(4):400
Store-operated Ca2+ entry (SOCE) is a major pathway for Ca2+ influx in non-excitable cells. Recent studies favour a conformational coupling mechanism between the endoplasmic reticulum (ER) Ca2+ sensor STIM1 and Ca2+ permeable channels in the plasma membrane to explain SOCE. Previous studies have reported a role for the cytoskeleton modulating the activation of SOCE; therefore, here we have investigated whether the interaction between STIM1 and the Ca2+ permeable channels is modulated by the actin or microtubular network. In HEK-293 cells, treatment with the microtubular disrupter colchicine enhanced both the activation of SOCE and the association between STIM1 and Orai1 or TRPC1 induced by thapsigargin (TG). Conversely, stabilization of the microtubules by paclitaxel attenuated TG-evoked activation of SOCE and the interaction between STIM1 and the Ca2+ channels Orai1 and TRPC1, altogether suggesting that the microtubules act as a negative regulator of SOCE. Stabilization of the cortical actin filament layer results in inhibition of TG-evoked both association between STIM1, Orai1 and TRPC1 and SOCE. Interestingly, disruption of the actin filament network by cytochalasin D did not significantly modify TG-evoked association between STIM1 and Orai1 or TRPC1 but enhanced TG-stimulated SOCE. Finally, inhibition of calmodulin by calmidazolium enhances TG-evoked SOCE and disruption of the actin cytoskeleton results in inhibition of TG-evoked association of calmodulin with Orai1 and TRPC1. Thus, we demonstrate that the cytoskeleton plays an essential role in the regulation of SOCE through the modulation of the interaction between their main molecular components. 相似文献
18.
BACKGROUND AND PURPOSE
The coordinate activity of hepatic uptake transporters [e.g. organic anion transporting polypeptide 1B1 (OATP1B1)], drug-metabolizing enzymes [e.g. UDP-glucuronosyltransferase 1A1 (UGT1A1)] and efflux pumps (e.g. MRP2) is a crucial determinant of drug disposition. However, limited data are available on transport of drugs (e.g. ezetimibe, etoposide) and their glucuronidated metabolites by human MRP2 in intact cell systems.EXPERIMENTAL APPROACH
Using monolayers of newly established triple-transfected MDCK-OATP1B1-UGT1A1-MRP2 cells as well as MDCK control cells, single- (OATP1B1) and double-transfected (OATP1B1-UGT1A1, OATP1B1-MRP2) MDCK cells, we therefore studied intracellular concentrations and transcellular transport after administration of ezetimibe or etoposide to the basal compartment.KEY RESULTS
Intracellular accumulation of ezetimibe was significantly lower in MDCK-OATP1B1-UGT1A1-MRP2 triple-transfected cells compared with all other cell lines. Considerably higher amounts of ezetimibe glucuronide were found in the apical compartment of MDCK-OATP1B1-UGT1A1-MRP2 monolayers compared with all other cell lines. Using HEK cells, etoposide was identified as a substrate of OATP1B1. Intracellular concentrations of etoposide equivalents (i.e. parent compound plus metabolites) were affected only to a minor extent by the absence or presence of OATP1B1/UGT1A1/MRP2. In contrast, apical accumulation of etoposide equivalents was significantly higher in monolayers of both cell lines expressing MRP2 (MDCK-OATP1B1-MRP2, MDCK-OATP1B1-UGT1A1-MRP2) compared with the single-transfected (OATP1B1) and the control cell line.CONCLUSIONS AND IMPLICATIONS
Ezetimibe glucuronide is a substrate of human MRP2. Moreover, etoposide and possibly also its glucuronide are substrates of MRP2. These data demonstrate the functional interplay between transporter-mediated uptake, phase II metabolism and export by hepatic proteins involved in drug disposition. 相似文献19.
在过去的几十年中,环境和生活方式的改变使得2型糖尿病患者的数量急剧增加, 其中一个重要的病理基础是胰岛素分泌缺陷。胰高血糖素样肽1(GLP-1)是一种由肠道细胞产生及分泌的多肽激素, 该激素以葡萄糖浓度依赖性方式促进胰岛β细胞分泌胰岛素, 调节血糖水平。研究表明GLP-1是糖尿病治疗中的一个有效靶点, 药物研发目前主要集中于GLP-1受体激动剂和降解酶抑制剂两个方面。以其强大的生物学活性为基础, GLP-1药物在临床上表现出高效、低副作用的显著优势。在此, 我们对GLP-1生物学和基于GLP-1的抗糖尿病药物研发进行综述。 相似文献
20.
Arthur A. Hancock Steven A. Buckner Michael E. Brune Sweta Katwala Ivan Milicic Lynne M. Ireland Patricia A. Morse Sheila M. Knepper Michael D. Meyer Christopher R. Chapple Russell Chess-Williams Amanda J. Noble Michael Williams James F. Kerwin 《Drug development research》1998,44(4):140-162
New compounds selective for α1A-adrenoceptors in the prostate may offer enhanced efficacy for benign prostatic hyperplasia (BPH), with fewer side effects than current treatment. A-131701 (3-[2-((3aR,9bR)-cis-6-methoxy-2,3,3a,4,5,9b,hexahydro-[1H]-benz[e]isoindol-2-yl)ethyl]pyrido[3′,4′:4,5]thieno [3,2-d]pyrimidine-2,4(1H,3H)-dione), from a novel class of benz[e]isolindole pyridothienopyrimidines and pyridothienopyrazines, is selective for α1a- and α1d-adrenoceptors in radioligand binding studies (0.22 nM at α1a-, 0.97 nM at α1d-) compared to α1b-sites (2.5 nM) and in isolated tissue bioassays (pA2 values of 8.9–9.0 for α1A-receptors in rat vas deferens or canine prostate strips, 9.1 at α1D-sites (rat aorta)), compared to 7.9 at α1B-sites (rat spleen). A-131701 also potently blocked radioligand binding to α1-adrenoceptors in canine and human prostatic membranes, but was considerably weaker at α2-adrenoceptors. In isoflurane-anesthetized dogs, A-131701 antagonized epinephrine-induced increases in intraurethral pressure (IUP) with a pseudo-pA2 value of 8.17. In spontaneously hypertensive rats, A-131701 caused transient decreases in mean arterial blood pressure (MABP) and transient tachycardia. The area under the curve (AUC0→60 min) for the hypotensive response was dose-related, with a log index value for A-131701 of 5.33, suggesting a selectivity of >600-fold comparing IUP to MABP effects. In pentobarbital-anesthetized dogs, A-131701 was more potent in blocking phenylephrine (PHE)-induced increases in IUP (pseudo-pA2 = 8.0) compared to concurrently measured MABP (pseudo-pA2 = 7.2), or sixfold selective. Doses greater than 1,000 nmol/kg i.v. of A-131701 were required to lower blood pressure by 10 mm Hg in these dogs (pED10 =. 5.57), indicating a uroselectivity ratio of >250, superior to doxazosin, terazosin, or tamsulosin. Thus, A-131701 is selective for α1A- and α1D- vs. α1B-adrenoceptors in vitro, and prostatic function vs. blood pressure effects in vivo, which may provide therapeutic advantages in the treatment of BPH. Drug Dev. Res. 44:140–162, 1998. © 1998 Wiley-Liss, Inc. 相似文献