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郭杭州  贾敬山 《药学学报》1987,22(8):608-611
本文报告了五个2-芳基-4-氰基咪唑类及三个2-芳基-4-氨基嘧啶化合物的电子轰击质谱。前五个都有基峰[M-(R-CH-NH)]+离子,后三个都有特征峰(M—HCN)+。从键能的角度探讨了其主要离子的裂解来源。  相似文献   

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丙酮醛缩二甲醇与氯乙烯格氏试剂反应得叔醇,然后经乙酐酰化制得1,2-二乙酰氧基-2-甲基-1-甲氧基-3-丁烯,进而水解得2-乙酰氧基-2-甲基-3-丁烯-1-醛,最后重排得到维生素A的关键中间体4-乙酰氧基-2-甲基-2-丁烯-1-醛,总收率约49%。  相似文献   

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Fused 2-Tetrazolyl-4-pyrones The synthesis of the 2-(1H-tetrazol-5-yl)-4-oxo-4H-[1]benzofuro[3,2-b]pyrane, -4-oxo-4H–[1]benzothieno[3,2-b]pyrane and -4,5-dihydro-5-alkyl-4-oxopyrano[3,2-b]indoles is described.  相似文献   

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4-(2-Amino-2-methylpropyl)phenols by Fluoride Ion Catalysed Reaction of 4-Hydroxybenzyl Alcohols with 2-Nitropropane The 4-hydroxybenzyl alcohols 1 can be converted into the 4-(2-methyl-2-nitropropyl)phenols 2 by a fluoride ion catalysed reaction with 2-nitropropane. Methylation of the phenolic hydroxy group yields the methyl ethers 7. The nitro compounds 2 and 7 can be converted to the amines 8 by catalytic hydrogenation. The amines 8 are building blocks in the synthesis of new β-sympathomimetic compounds.  相似文献   

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为考察4′-去甲基表鬼臼毒素4位上取代基结构变化与抗肿瘤活性的关系,设计并合成了23个标题化合物。体外L1210白血病细胞与KB细胞生长抑制试验的结果表明,化合物11,16和18的抗肿瘤活性超过依托泊甙,化合物8的活性与依托泊甙相当。  相似文献   

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Phytobiological Investigation of Derivatives of 2-Amino-4-carbethoxy-thiazole. Part II The cytostatic effect of allyl- and halogenacetyl-derivatives led us to test phytobiologically a series of derivatives of 2-amino-4-carbethoxy-thiazole. The examination on the meristem of roots from Triticum vulgare Vill. was carried out in a caffeine containing solution. Histological tests showed a mitodepressive and mitostatic effect; substance IV seems to promise the best result.  相似文献   

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证明了不定方程x4-y4=z2在Z[2~(1/2)]中只有平凡解。  相似文献   

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张磊  张灿 《中南药学》2012,10(8):588-590
目的 优化(2R,4R)-4-甲基-2-哌啶甲酸乙酯的合成工艺.方法 以S-(-)-α-甲基苄胺为原料,与乙醛酸乙酯反应得到[(S)-1-苯乙基亚胺基]乙酸乙酯,与异戊二烯进行环合后,再经不对称氢化和脱保护反应制得(2R,4R)-4-甲基-2-哌啶甲酸乙酯.结果 总收率从17.0%提高至47.6%.结论 本工艺可有效地降低生产成本.  相似文献   

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4-(2',4'- Difluorobiphenyl-4-yl)-2-methylbutyric acid (deoxoflobufen, VUFB 19053, CAS 847475-35-8) has been developed as a new omega-biphenyl-alkanoic acid and studied in comparison with the racemic form of 4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid (flobufen, CAS 112344-52-2). The compounds were tested in a series of models including acute inflammation induced by carrageenan, adjuvant arthritis, in vitro inhibition of the leuktotriene B4 (LTB4) production, reaction of the graft versus the host (GVHR), production of specific antibodies against ovalbumin, peritoneal exudate formation induced by thioglycollate and phagocytosis of thioglycollate-stimulated mouse peritoneal macrophages. Deoxoflobufen exhibited strong anti-inflammatory, antiarthritic and immunomodulatory effects in most of the performed tests. Anti-inflammatory and antiarthritic effects are fully comparable with those of flobufen, however, the compound is less toxic and has apparently stronger immunomodulating effects.  相似文献   

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Previous studies found the lipid peroxidation product 4-hydroxynon-2-enal (4HNE) to be both a substrate and an inhibitor of mitochondrial aldehyde dehydrogenase (ALDH2). Inhibition of the enzyme by 4HNE was demonstrated kinetically to be reversible at low micromolar aldehyde but may involve covalent modification at higher concentrations. Structurally analogous to 4HNE is the lipid peroxidation product 4-oxonon-2-enal (4ONE), which is more reactive than 4HNE toward protein nucleophiles. The goal of this work was to determine whether 4ONE is a substrate or inhibitor of human ALDH2 (hALDH2) and elucidate the mechanism of enzyme inhibition by 4HNE and 4ONE. Both 4ONE and its glutathione conjugate were found to be substrates for the enzyme in the presence of NAD. At low concentrations of 4ONE (< or = 10 microM), hALDH2 catalyzed the oxidation of 4ONE to 4-oxonon-2-enoic acid (4ONEA) with a maximal yield of 5.2 mol 4ONEA produced per mol of enzyme (monomer). However, subsequent analysis of hALDH2 activity toward propionaldehyde revealed that both 4ONE and the oxidation product, 4ONEA, were potent, irreversible inhibitors of the enzyme. In contrast, inhibition of hALDH2 by a high concentration of 4HNE (i.e., 50 microM) was primarily reversible. The reactivity of 4ONEA toward glutathione was measured and found to be comparable to that of 4HNE, indicating that the 4ONE-oxidation product is a reactive electrophile. hALDH2/NAD was incubated with 4HNE, 4ONE, and 4ONEA, and mass spectral analysis of tryptic peptides revealed covalent modification of an hALDH2 active site peptide by both 4ONE and 4ONEA. These data demonstrate that hALDH2 catalyzes the oxidation of 4ONE to 4ONEA; however, the product 4ONEA is a reactive electrophile. Furthermore, both 4ONE and 4ONEA are potent, irreversible inhibitors of the enzyme.  相似文献   

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Aminophenols and halogenated anilines induce nephrotoxicity and mild hepatotoxicity in rats. In this study, the in vivo and in vitro nephrotoxic potential of 4-amino-2-chlorophenol and 2-amino-4-chlorophenol, monochlorinated aminophenols and potential metabolites of 3-chloroaniline, was evaluated. Hepatotoxicity of both compounds was also examined in vivo. Male Fischer 344 rats (four/group) were administered 4-amino-2-chlorophenol hydrochloride (0.4, 0.8 or 1.0 mmol/kg), 2-amino-4-chlorophenol hydrochloride (0.4, 0.8 or 1.2 mmol/kg) or vehicle intraperitoneally (i.p.) and renal and hepatic function monitored for 48 h. Administration of 4-amino-2-chlorophenol (0.8 mmol/kg) induced nephrotoxicity, while only minor changes in kidney function were observed following administration of 0.4 mmol/kg of 4-amino-2-chlorophenol or 0.8 mmol/kg of 2-amino-4-chlorophenol. Increasing the dose of 4-amino-2-chlorophenol to 1.0 mmol/kg or 2-amino-4-chlorophenol to 1.2 mmol/kg resulted in lethality. Nephrotoxicity induced by 4-amino-2-chlorophenol was characterized by diuresis, increased proteinuria, glucosuria, hematuria, elevated blood urea nitrogen (BUN) concentration and kidney weight, and marked proximal tubular damage, while 2-amino-4-chlorophenol induced milder effects on renal function and transient oliguria instead of diuresis. No hepatotoxicity was observed with either compound at any dose tested. In the in vitro studies, the direct effects of 4-amino-2-chlorophenol or 2-amino-4-chlorophenol on organic ion accumulation, pyruvatestimulated gluconeogenesis and lactate dehydrogenase (LDH) leakage were determined using renal cortical slices. 4-Amino-2-chlorophenol and 2-amino-4-chlorophenol were almost equally effective in inhibiting organic anion or cation uptake and gluconeogenesis or increasing LDH leakage, although small differences in the minimum effective concentrations were present (minimum effective concentration, 0.01–0.5 mM range). These results demonstrate that 4-amino-2-chlorophenol is a more potent nephrotoxicant than 2-amino-4-chlorophenol in vivo. The results also indicate that the addition of a chloride group to aminophenols enhances renal toxicity.  相似文献   

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2-氨基-4′-氯-二苯甲酮的合成新法   总被引:5,自引:0,他引:5  
邻苯二甲酸酐与氯苯进行付-克反应得到羧酸。然后经酰氯化。酰胺化制得2-对氯苯甲酰基苯甲酰胺,最后经霍夫曼降解合成2-氨基-4′-氯-二苯甲酮。反应条件温和。操作简便,收率78.3%。  相似文献   

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Reaction of ethyl 2-pyridyl acetates and activated malonates (magic malonates) leads to 1-ethoxycarbonyl-2-hydroxy-quinolizin-4-ones, which yield the corresponding C-1 unsubstituted derivatives by hydrolysis and decarboxylation. These compounds are catalytically hydrogenated to afford the corresponding tetrahydro derivatives. Significant inhibitory effects on mycobacterium tuberculosis H 37 Ra are shown, a structure-activity relationship is discussed.  相似文献   

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