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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
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对甲氧基苯胺和乙醛酸乙酯依次经缩合、(S')-脯氨酸催化不对称Mannich反应和DBU不对称转化制得(2S,3R)-2-(4-甲氧基苯胺基)-3-甲基-4-氧代戊酸乙酯,再经CAN氧化脱保护、硼氢化钠还原和氧氧化锂水解得(2S,3R,4S)-4-羟基异亮氨酸,总收率约30%. 相似文献
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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
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2-氨基-4-甲基吡啶在过量浓盐酸/亚硝酸钠作用下与氯化亚铜/盐酸反应后,在偶氮二异丁腈(AIBN)作用下与硫酰氯反应制得2-氯-4-(氯甲基)吡啶,再在DMF中与哌啶缩合,得到拉呋替丁的关键中间体2-氯-4-(哌啶-1-基甲基)-吡啶,总收率约62%. 相似文献
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3,4-二氟苯胺在三乙胺存在下与二硫化碳生成芳基取代的二硫代氨基甲酸后与氯甲酸乙酯反应得到3,4-二氟苯基异硫氰酸酯,先后与由丙二酸二乙酯在无机碱中成的盐和氯甲基甲醚反应后加热环合,得到氟喹诺酮类抗菌剂普卢利沙星的中间体6,7-二氟-4-羟基-2-甲氧甲硫基-3-喹啉羧酸乙酯,总收率85.7%. 相似文献
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对甲氧基苯甲醛(3)和2-氨基乙醇进行还原胺化反应得2-(4-甲氧基苄胺基)乙醇(4),4和乙醛酸经成环反应得2-羟基-4-对甲氧基苄基吗啉-3-酮(5),5和三氟乙酐反应得6后与(R)-1-[3,5-二(三氟甲基)苯基]乙醇(7)缩合,再经结晶诱导不对称转化、格氏反应、氢化脱保护及成盐反应制得阿瑞吡坦关键中间体(2R,3S)-2-[(R)-1-[3,5-二(三氟甲基)苯基]乙氧基]-3-(4-氟苯基)吗啉盐酸盐,总收率约18%(以3计)。 相似文献
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对甲氧基肉桂酸经LiAlH4还原、溴代得到3-(4-甲氧基苯基)溴丙烷,与4-哌啶甲酸乙酯反应得到的1-[3-(4-甲氧基苯基)丙基]哌啶-4-甲酸乙酯经还原后与二苯甲醇醚化,得到钾离子通道阻断剂UK-78282,总收率58%. 相似文献
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P L Ornstein D D Schoepp M B Arnold N D Jones J B Deeter D Lodge J D Leander 《Journal of medicinal chemistry》1992,35(17):3111-3115
The tetrazole-substituted amino acid (+/-)-(2SR,4RS)-4-(1H-tetrazol-5-ylmethyl)pip eri dine-2-carboxylic acid (LY233053, (+/-)-1) was resolved into its constituent enantiomers by treatment of a key intermediate in the synthesis of the racemic amino acid, ethyl (+/-)-cis-4-(cyanomethyl)-N-allylpiperidine-2-carboxylate, with either 2S,3S- or 2R,3R-di-p-toluoyltartaric acid. These resolved amines were then converted as for the racemate to the amino acids (-)-1 and (+)-1. The activity of this potent and selective NMDA antagonist was found to reside with the (-)-isomer of 1 (LY235723). X-ray crystallographic analysis of the 2S,3S-di-p-toluoyltartaric acid salt of ethyl cis-4-(cyanomethyl)-N-allylpiperidine-2-carboxylate showed that the resolved amine, and thus (-)-1, possessed the 2R,4S absolute stereochemistry. Affinity for the NMDA receptor was determined using the specific radioligand [3H]-(2SR,4RS)-4-(phosphonomethyl)piperidine-2-carboxylic acid ([3H]CGS 19755; IC50 = 67 +/- 6 nM), and selective NMDA antagonist activity was determined using a cortical slice preparation (IC50 versus 40 microM NMDA = 1.9 +/- 0.24 microM). This compound also demonstrated potent NMDA antagonist activity in vivo following systemic administration through its ability to block NMDA-induced convulsions in neonatal rats, NMDA-induced lethality in mice, and NMDA-induced striatal neuronal degeneration in rats. 相似文献
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报道以(一)-奎尼酸为手性源有效地合成(1R,2R,4S,5R)-1,4-二羟基-3-二苯叔丁硅氧基-6-氧代双环[3.2.1]-辛-7-酮的方法。 相似文献
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T Toyo-oka T Kamishiro K Hara N Nakamura M Kitahara T Masaki 《Arzneimittel-Forschung》1986,36(2):190-193
The synthetic protease inhibitor bis[ethyl(2R,3R)-3-[(S)-methyl-1-[4-(2,3,4-tri-methoxyphenyl-methyl) piperazine-1-ylcarbonyl]butyl-carbonyl]oxiran-2-carboxylate] sulfate (NCO-700) suppressed both activities of calcium-activated neutral protease and cathepsin B isolated from cardiac muscle, showing 50% inhibition at 46 and 0.8 mumol/l, respectively. A kinetics study using 14C-labelled NCO-700 suggested its incorporation into cultured myocardial cells, demonstrating the half-maximal saturation time at 17 min. Under both aerobic and hypoxic conditions, the reagent inhibited the peptide release from cultured myocardial cells dose-dependently. The amino acid release from heart slices of adult rabbit was also blocked by the drug under hypoxic and glucose-depleted condition. These data and the myocardial infarction size reducing action of NCO-700 might support the view that NCO-700 sensitive protease(s) - possibly, calcium-activated neutral protease and/or cathepsin B - is (are) working to induce an irreversible proteolysis in the process of myocardial cell degradation. 相似文献
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3-甲基吡啶-2-甲酸甲酯(2)经氧化、硝化和还原反应制得4-氨基-3-甲基吡啶-2-甲酸甲酯(5),然后经改进的Balz-Schiemann反应制得4-氟-3-甲基吡啶-2-甲酸甲酯(1),以2计总收率约18%。 相似文献
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合成了两种可回收利用的小分子配体,并在两种不同体系的Sharpless不对称二羟化反应中用于催化肉桂酸乙酯,以合成紫杉醇的重要中间体(2R,3S)-2,3-二羟基-3-苯丙酸乙酯.结果表明,两种配体在叔丁醇-水(1:1)和丙酮-水(10:1)体系中的催化性能均良好,收率85%~95%,ee可达95%以上,且重复使用3次后收率和ee基本不变. 相似文献
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目的研究白刺链霉菌(Streptomyces albospinus)15-4-2发酵液中的抗耐甲氧西林金葡菌(MRSA)活性成分。方法通过活性跟踪,采用柱层析等方法对白刺链霉菌15-4-2的次生代谢产物进行分离纯化。采用光谱分析对活性成分进行结构解析。结果分离鉴定了7个化合物,其结构分别为N-(2-羟基-1-(4-甲氧基苯基)乙基)乙酰胺(1)、2-(4-甲氧基苯基)-2-(丙胺基)乙醇(2)、cytoxazone(3)、对羟基苯甲酸(4)、(2S,3R)-3-羟基-2-甲基丁酸(5)、对甲基苯酚(6)和1,4-二甲氧基苯(7)。结论抗菌活性测试结果表明化合物1、3、4、5和6具有抗耐甲氧西林金黄色葡萄球菌(MRSA)活性。其中,1、3、4和5的抗耐甲氧西林金黄色葡萄球菌活性为首次报道。 相似文献
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目的 分析血清抗M型磷脂酶A2受体(PLA2R)抗体、肾小球PLA2R表达及IgG亚型沉积在膜性肾病中的作用,探讨其在膜性肾病中的诊断价值. 方法 选取经肾活检术诊断的膜性肾病79例,其中特发性膜性肾病(IMN)65例,继发性膜性肾病(SMN)14例(其中11例Ⅴ型狼疮肾炎,2例乙型肝炎病毒相关性膜性肾病,1例梅毒相关性膜性肾病).血清抗PLA2R抗体应用欧蒙间接免疫荧光实验(IIFT)检测,肾小球PLA2R表达及IgG亚型沉积采用免疫荧光法,并比较特发性膜性肾病和继发性膜性肾病2组患者临床资料是否有差异. 结果 65例IMN患者中,肾小球PLA2R表达阳性者57例(87.7%);血清抗PLA2R抗体阳性者47例(72.3%);IgG4亚型沉积阳性者59例(90.8%).14例SMN患者肾小球PLA2R表达均阴性,血清抗PLA2R抗体阳性者2例(14.3%),IgG4亚型沉积阳性者4例(28.6%).肾小球PLA2R表达阳性诊断IMN灵敏度为87.7%,特异度为100%;血清抗PLA2R抗体阳性诊断IMN灵敏度为72.3%,特异度为85.7%.IMN患者中肾小球PLA2R表达、血清抗PLA2R抗体、IgG4亚型沉积阳性比例高于SMN.2组患者临床资料在性别构成比存在统计学差异,年龄、白蛋白、血肌酐、总胆固醇、24小时尿蛋白定量、肾小球滤过率2组差异无统计学意义(P>0.05). 结论 IMN患者中肾小球PLA2R表达阳性率高,在膜性肾病鉴别诊断中具有优势作用. 相似文献
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P Franchetti G Cristalli M Grifantini L Cappellacci S Vittori G Nocentini 《Journal of medicinal chemistry》1990,33(10):2849-2852
Condensation of 3,4,6-tri-O-benzoyl-2,5-anhydro-D-allonyl chloride (4) with ethyl 2-amino-2-cyanoacetate (5) provided 2-[(3',4',6'-tri-O-benzoyl-2',5'-anhydroallonyl)amino]-2-cyanoa cetate (6). Compound 6 was treated with hydrogen chloride gas to give ethyl 5-amino-2-(2',3',5'-tri-O-benzoyl-beta-D- ribofuranosyl)oxazole-4-carboxylate (8). Reductive dediazotization of blocked nucleoside 8 provided ethyl 2-(2',3',5'-tri-O- benzoyl-beta-D-ribofuranosyl)oxazole-4-carboxylate (10), which after deblocking with sodium methoxide and ammonolysis was converted to 2-beta-D-ribofuranosyl-oxazole-4-carboxamide (oxazofurin, 3), an analogue of the antitumor and antiviral C-nucleoside tiazofurin (1). Oxazofurin (3) was found to be cytotoxic toward B16 murine melanoma cells in culture but inactive against murine leukemia P388 and L1210. 相似文献