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1.
Using MNDO calculations, ground state structures of 11 N-(hydroxymethyl)amides were predicted to have pyramidal nitrogens and an s-Z conformation. The results compare favourably with ab initio calculations and with X-ray data except that MNDO tends to predict twist angles around partial double bonds which are too large. A correlation was found between N-CH2OH bond length and the logarithm of the half-life under physiological conditions. MNDO ground state structures for five N-(hydroxymethyl)amide anions were calculated to have s-E conformations and their N-CH2OH bond lengths also correlated with the half-lives of the N-(hydroxymethyl)amides. These correlations may be valuable in assessing potential anti-tumour activity.  相似文献   

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The title compound is an isomer, differing only by the shift of a methyl group, of the anti-cancer agent ethyl 4-(3-hydroxymethyl-3-methyltriazen-1-yl) benzoate; yet its half-life at physiological pH is only one-third as long. It forms crystals with triclinic symmetry, space group P1, and unit cell dimensions a = 6.184 (2), b = 7.214 (2), c = 14.575 (2) A, alpha = 89.61 (2), beta = 79.96 (2), gamma = 68.76 (2)0. Its labile N-CH2OH bond is slightly shorter than that of the more stable isomer but becomes almost equal after optimization of geometry by semi-empirical molecular orbital techniques. Calculated heats of formation are virtually identical for these compounds, as they are for the daughter species after loss of CH2O. The hydroxyl group forms an intermolecular hydrogen bond to a carboxyl oxygen atom in preference to the less negative triazene N(1).  相似文献   

5.
Compounds 9 and 13 were synthesized, and their structures and stereochemistry were elucidated by spectroscopic methods. In competition binding experiments, specific [(3)H]-PGE(2) binding was significantly displaced by compound 9 and, to a lesser extent, by 13, in a dose-dependent manner. The biological properties of compound 9 were studied on HL-60 cells, and several effects were found related to those of PGE(2). Compound 9 increases c-fos mRNA level as does PGE(2) and antagonizes TPA-induced terminal differentiation.  相似文献   

6.
含哌嗪环的三唑醇类化合物的合成及体外抗真菌活性   总被引:1,自引:0,他引:1  
目的设计合成含哌嗪环侧链的三唑醇类化合物并研究其体外抗真菌活性。方法以2-氯-2′,4′-二氟苯乙酮为起始原料经多步反应合成目标化合物,化合物结构经IR、^1H-NMR谱确证;选择8种真菌为实验菌株,按国际标准抗真菌敏感性实验方法测定体外抑菌活性。结果设计合成了11个新化合物。所有目标化合物对8种真菌均具有一定的抑制作用。结论多个目标化合物的抗真菌活性明显高于阳性对照药氟康唑,其中化合物11具有广谱、高活性的优点,其体外抗真菌活性与对照药伊曲康唑相当,有进一步研究开发的价值。  相似文献   

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(-)-(2R,4R)-1-(2-Hydroxymethyl-1,3-dioxolan-4-yl)thymine (DOT) is the first thymidine kinase-activated nucleoside that is significantly active against all of the clinically significant NRTI-resistant HIV-1 mutants, including AZT (D67N/K70R/T215Y/K219Q), Tenofovir (K65R), and Lamivudine (M184V). To understand the molecular mechanism of drug resistance and the antiviral activity of DOT against drug-resistant RTs, molecular modeling studies of DOT-TP complexed with the wild-type (WT) and mutated RT were conducted. The key reason for this interesting antiviral activity profile is the presence of a dioxolane ring.  相似文献   

8.
The stability of metabolically-generated N-(hydroxymethyl) compounds was investigated using a series of N-methylbenzamides as model substrates. N-(Hydroxymethyl)-benzamide was characterized as a major metabolite of N-methylbenzamide in vitro, and was also identified as a urinary metabolite of N-methylbenzamide. N-(Hydroxymethyl) compounds were also found as metabolites of 4-chloro-N-methylbenzamide and 4-t-butyl-N-methylbenzamide in vitro. Thus substitution in the 4-position of the phenyl ring of derivatives of N-(hydroxymethyl)-benzamide did not affect their stability sufficiently to cause degradation to formaldehyde under the conditions used. N-(Hydroxymethyl)-N-methylbenzamide was identified as a metabolite of N, N-dimethylbenzamide in vitro. However, N-(hydroxymethyl)-N-methylbenzamide was less stable than N-(hydroxymethyl)-benzamide under alkaline conditions. Furthermore, N-(hydroxymethyl)-N-methylbenzamide, unlike N-(hydroxymethyl)-benzamide and its 4-substituted derivatives, was positive in the colorimetric assay for formaldehyde, presumably because of its degradation to produce formaldehyde. Thus substitution on the nitrogen atom which bears the methyl group in N-methylbenzamide markedly affected the stability of the N-methylol produced during oxidative metabolism. N-Formylbenzamide was identified as a metabolite of N-methylbenzamide in suspensions of mouse hepatocytes and also in vivo. The mechanism for its production probably involves the generation of N-(hydroxymethyl)-benzamide.  相似文献   

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基于计算机辅助药物设计系统及靶酶模建的需要。根据氮唑类抗真菌药物的构效关系和作用机理。设计合成了15个1-(1H-1,2,4-三唑-1-基)-2-(2,4-二氟苯基)-3-取代-2-丙醇类化合物,均为首次报道。运用微量注偌倍比稀释法对8种常见致病真菌进行外抑菌试验。化合物Ⅳg具有较强的体外抗真菌活性。  相似文献   

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Novel histamine H(3)-receptor antagonists possessing a 4-(3-(phenoxy)propyl)-1H-imidazole structure generally substituted in the para-position of the phenyl ring have been synthesized according to Mitsunobu or S(N)Ar reactions. With in vitro and in vivo screening for H(3)-receptor antagonist potency, the carbonyl-substituted derivatives proved to be highly active compounds. A number of compounds showed in vitro affinities in the subnanomolar concentration range, and the 4-hexanoyl (10) and 4-acetyl-3-methyl (29) substituted derivatives showed in vivo antagonist potencies of about 0.1 mg/kg after po administration. Many proxifans were also tested for their affinities at other histamine receptor subtypes thereby demonstrating their pronounced H(3)-receptor subtype selectivity. Since the cyclopropyl ketone derivative 14 (ciproxifan) had high affinity in vitro as well as high potency in vivo, it was selected for further studies in monkeys. It showed good oral absorption and long-lasting, dose-dependent plasma levels making it a promising compound for drug development.  相似文献   

12.
艾他培南关键中间体的合成   总被引:3,自引:0,他引:3  
目的改进艾他培南关键中间体(2S,4S)-4-乙酰硫-1-对硝基苄氧羰基-2-(3-烯丙氧羰基苯氨甲酰基)吡咯烷的合成工艺。方法以反-4-羟基-L-脯氨酸为原料经氨基、羧基保护;羟基甲磺酰化和乙酰硫化;脱去羧基保护基;与3-氨基苯甲酸烯丙酯缩合得目标物。结果与结论反-4-羟基-L-脯氨酸经6步反应制得目标物,总收率为49·4%,各步反应不需繁琐的柱色谱分离,操作简便,适合工业生产。  相似文献   

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The crystal structures of 2,6-dimethyl-3,5-dicarbomethoxy-4-(2-nitrophenyl)-1,4-dihydropyridine (Nifedipine) and the 3-cyano-, 4-(dimethylamino)- and 2,3,4,5,6-pentafluorophenyl derivatives were determined. The 1,4-dihydropyridine ring in all four compounds has a boat-type conformation with varying degrees of puckering at the C4 position. Increasing distortion from planarity at this position shows a limited correlation with decreasing biological activity, determined as the ability to inhibit the Ca2+-dependent muscarinic-induced mechanical responses of guinea pig ileal longitudinal smooth muscle.  相似文献   

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目的设计合成含氧取代的叔丁基三唑醇类化合物并研究其体外抗真菌活性。方法以一氯频那酮为起始原料经多步反应合成目标化合物,化合物结构经1H-NMR谱、IR谱确证;选择8种真菌为实验菌株,按国际标准抗真菌敏感性实验方法测定体外抑菌活性。结果与结论合成了12个新化合物。所有目标化合物对8种真菌均具有一定的抑制作用。可以将现有的三唑醇类抗真菌药物结构中的2,4-二氟苯基替换成其他疏水性基团来设计抗真菌化合物。  相似文献   

16.
The hydrolysis of 1-(4-nitrophenyl)-3-methyltriazene in aqueous solution has been studied over a pH range of 3-14. The effect of the anionic and cationic surfactants (sodium lauryl sulfate and hexadecyltrimethylammonium bromide) on the rate of hydrolysis was investigated. The quaternary ammonium bromide causes a rate decrease at all pH values studied, while sodium lauryl sulfate enhances the acid-catalyzed hydrolysis and decreases the observed rate constants in the pH-independent region. The results are discussed in terms of the current theory of micellar effects.  相似文献   

17.
The metabolism of two glycosylnitrosoureas, 1-(2-chloroethyl)-3-[1'-(5'-p-nitrobenzoyl-2',3'-isopropylidene)-alpha, beta-D-ribofuranosyl]-1-nitrosourea (RFCNU) and 1-(2-chloroethyl)-3-(2',3',4'-tri-O-acetyl-alpha, beta-D-ribopyranosyl)-1-nitrosourea (RPCNU), has been investigated in the rat. With the label on the carboxyl moiety of RFCNU, we have shown that hydrolysis of the 4-nitrobenzoyl ester occurred to a large extent in vivo; 4-nitrobenzoic acid and its glucuronide were the major urinary metabolites. Two other minor metabolites and their glucuronides were identified as 4-aminobenzoic acid and 4-acetamidobenzoic acid. With the label on the chloroethyl moieties of RFCNU and RPCNU, we have shown that chloroethanol was a major degradation product of this alkylating part of the molecule. The concentration of chloroethanol in plasma vs. time has been determined. In urine, four metabolites derived from alkylated glutathione, namely thiodiacetic acid and its sulfoxide, N-acetylcarboxymethylcysteine, and N-acetylhydroxyethylcysteine, have been identified.  相似文献   

18.
The synthesis and in vitro activity of the 3-(O-substituted oxyiminoacetamido)-2-azetidinones (IV) possessing a tetrazole moiety at N-1 position are described. The introduction of lipophilic functions into the oxyimino moiety gave in some good activity against staphylococci, but decreased activity against Gram-negative bacteria. In contrast, the introduction of hydrophilic functions such as carboxycyclobutane resulted in strong activity against Gram-negative bacteria including Pseudomonas aeruginosa, and no or very small activity against the staphylococci.  相似文献   

19.
2-羟甲基-青霉烯-3-羧酸对硝基苄酯的制备   总被引:2,自引:0,他引:2  
目的研究(5R,6S)-2-羟甲基-6-[(1R)-1-叔丁基-2-二甲基硅氧乙基]-青霉烯-3-羧酸对硝基苄酯的合成方法.方法以商品化的小四环为原料,经噻酸亲核取代、与对硝基苄基草酰氯反应、与亚磷酸三乙酯反应、加热环合、脱去保护基生成目标化合物1.结果与结论设计的合成路线经4步反应,总收率为23%,合成路线简便易行,适宜大规模生产.所合成的中间体及目标产物经核磁共振氢谱确证.  相似文献   

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