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1.
某些有机锗化物,例如β-羧乙基锗倍半氧化物及其衍生物能诱发干扰素,对癌症有一定疗效,日本专利报道丙酰胺基锗倍半氧化物及其衍生物也具有抗癌活性[2,3],白明章等曾合成丙酰芳胺基锗倍半氧化物[4]。  相似文献   

2.
A series of N-(trifluoromethyl-2-pyridinyl)alkane- and arenesulfonamides 2-5 have been synthesized by the substitution reaction of 2-chloro(trifluoromethyl)pyridines 6 with alkane- and arenesulfonamides 7. Their inhibitory activities against secretory phospholipase A? of porcine pancreas were examined and the analog N-[4,5-bis(trifluoromethyl)-2-pyridinyl]-4-trifluoromethylbenzenesulfonamide 4i was shown to have the highest inhibitory activity, with an IC(50) value of 0.58 mM.  相似文献   

3.
以樟脑衍生物(-)-莰烷磺内酰胺为原料,经N-(E-2-烷烯酰基)莰烷-10,2-磺内酰胺与烷基格氏试剂的不对称Michael加成反应,LiAlH4还原断裂,3-甲基已醇的碘代反应及有机镉试剂与丙酰氯的偶联反应制得(R)-和(S)-石蚕蛾雄性性信息素6-甲基于-3-壬酮,其光学纯度达96%ee以上。  相似文献   

4.
Beckmann rearrangement of N-[3-(1-hydroxyimino)ethyl-2,2-dimethylcyclobutyl]acetylanthranilic acid, and its 5-bromo and 4-chloro derivatives gives the corresponding N-(3-acetylamino-2,2-dimethylcyclobutyl)acetylanthranilic acids. Treatment of these acylanthranilic acids with formamide gives 2-(3-acetylamino-2,2-dimethylcyclobutyl)methyl-4(3H)-quinazoline and its 6-bromo and 7-chloro derivatives.  相似文献   

5.
A series of secondary N-1-(2-chloroalkylidene)amines has been prepared by condensation of disubstituted acetaldehydes with primary amines followed by chlorination with N-chlorosuccinimide in carbontetrachloride. A study of the reactivity of these N-homologues of α-chloroaldehydes is described. Treatment of the title compounds with sodium methoxide in methanol gave high yields of α,β-unsaturated aldimines. However, N-1-(2-chloro-2-methylpropylidene)amines afforded a mixture of elimination and rearrangement products, which proceeded via an aziridine intermediate. On the other hand, α-phenyl-substituted α-chloro aldimines on treatment with methoxide in methanol underwent α-substitution, consistent with an SN1 mechanism. Powerful nucleophiles such as sodium thiophenolate in methanol and sodium azide in acetone caused α-substitution. Reaction of α-chloro aldimines with Grignard reagents produced coupling of two aldimine units or α-alkylation. Finally the reactivity of α-chloro aldimines was compared with the reactivity of the corresponding oxygen-analogues, i.e. α-chloro aldehydes.  相似文献   

6.
β-三氯锗取代丙酰氯1a~1c与(R)TTCA酯反应, 得到光学活性的(R)-N-(β-三氯锗取代丙酰基)TTCA酯3a~3d([α]D^2^0-86.00~-94.35ⅲ)及光学活性的β-三氯锗取代丙酰氯2a~2d。化合物3a~3d经水解得到(R)-N-(β-取代丙酰基)TTCA酯基锗倍半氧化物4a~4d, [α]D^2^0-44.48~-77.00ⅲ。用半经验量子化学MNDO方法研究了反应物和产物最优构型的电子结构及反应的焓变。  相似文献   

7.
The reaction of 5-chloro(bromo)-1-methyl(1,2-dimethyl)-4-nitroimidazoles and 4-chloro-1-methyl-5-nitroimidazole with amino acids has been studied. This has enabled a series of N-(4-nitro-5-imidazolyl)- and N-(5-nitro-4-imidazolyl)-substituted amino acids to be synthesized. Esters of some of these acids have been obtained.For Part 97 see [1].Center for Drug Chemistry, All-Russian Research Institute for Pharmaceutical Chemistry, Moscow 119815. Novokuznetsk Research Institute for Pharmaceutical Chemistry, Novokuznetsk 654034, Russia. Zaporozhye State Medical University, Zaporozhye 330074, Ukraine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 48–53, January, 1999.  相似文献   

8.
本文在Ni(PPh3)2 Cl2催化下顺利实现了不同取代基2-氯嘧啶与芳基硼酸的Suzuki-Miyaura偶联反应.实验表明,取代基的电子效应和空间位阻效应对2-氯嘧啶的反应活性影响较小.该反应产率良好,官能团耐受性好,为2-芳基嘧啶衍生物的合成提供了一类简单有效的方法.  相似文献   

9.
J.J. Brunet  B. Fixari  P. Caubere 《Tetrahedron》1974,30(16):2931-2937
Condensations of amines with 1-chloro cycloheptene in the presence of complex base (NaNH2-t-BuONa) lead to mixtures of enamines and 1,2-cycloheptadiene dimer. Under the same conditions, 2-chloro and 3-chloro bicyclo [3.2.1] oct-2 enes yield only enamines via bicyclo [3.2.1] oct-2 yne. The mechanism of these reactions depends not only upon the halogeno derivatives but also upon “reaction media.” The general problem of the interpretation of elimination-addition reactions is discussed.  相似文献   

10.
双臂型方酰胺多齿配体的合成(三)   总被引:1,自引:0,他引:1  
Six new multidentates, chromogenic squaraine ligands, 3 ~8 are synthesized. In butanol-toluene couple medium, o-aminophenol reacts with squaric acid to give 1, 3-bissubstituted product 2 and monosubstituted product 3. It is noteworthy that reactions of N- hydroxyethyl-(2-amino-4-chloro) aniline and N-hydroxyethyl-(4-chloro-2- nitro) aniline with squaric acid do not give isosquaramide, 1, 3- substituted derivate but squaramide, 3, 4-substituted derivates 7 and 8.  相似文献   

11.
The complementary 1,omega-thymine, 1,omega-adenine, and 1,omega-(thymine, adenine) bolaamphiphiles, [N,N'-bis[3-(2,4-dihydroxy-5-methylpyrimidine-1-yl)propionyl]1,n-diaminoalkane [T-n-T (n = 10, 11, 12)], N, N'-bis[3-(6-aminopurine-9-yl)propionyl]1,n-diaminoalkane [A-n-A (n = 10, 11, 12)], and N-[3-(2,4-dihydroxy-5-methylpyrimidine-1-yl)propionyl], N'-[3-(6-aminopurine-9-yl)propionyl]1,n-diaminoalkane [T-n-A (n = 10, 11, 12)], respectively] have been synthesized. The spontaneous homo- and heteroassembly of these nucleobase-based bolaamphiphiles has been studied by light microscopy, energy-filtering transmission electron microscopy, FT-IR, and powder X-ray diffraction analyses. The achiral T-10-T bolaamphiphile produced in 10% ethanolic/aqueous solutions unprecedented double-helical ropes of 1-2 microm in widths and several hundred micrometers in length, whereas the complementary homologue A-10-A gave only microcrystalline solids of 1-10 microm in size. In contrast, an equimolar mixture of T-10-T and A-10-A yielded supramolecular fibers of 15-30 nm in width. (1)H NMR, CD, and UV studies of solution photoreactions of T-10-T suggested that under natural light the chiral rope formation is triggered by photodimerization of trace amounts of the thymine moieties in the T-10-T assemblies. Complementary hydrogen bond formation between the thymine-adenine heterobase pairs was found to prevent such a photoreaction and resulted in no chiral rope formation. The heteroditopic T-12-A bolaamphiphile self-assembled to form supramolecular fibers. Multilamellar organization was proposed for the homo- and heteroassemblies made of T-n-T and A-n-A.  相似文献   

12.
A rapid dechlorination method of N-chloro poly(hexamethylene adipamide) and N-chloro poly(ε-caprolactam) to the corresponding polyamides was studied. This method can be used for molecular weight determinations of N-chloro polyamides by viscosimetric measurements. The dechlorination was achieved in formic acid solution by the reaction of N-chloro polyamides with trialkyl phosphites. The reaction was exothermic and vigorous and was applied to a series of products of various degrees of N-chlorination covering the range of 0–100%. No N—Cl was detected by iodimetric titration of the dechlorination products. The dechlorination of N-chloro polyamides was demonstrated by infrared (IR) spectroscopy. No significant molecular weight reduction except that taking place in the N-chlorination reaction of poly(hexamethylene adipamide) was observed.  相似文献   

13.
The reaction of propionyl radical with oxygen has been studied using the full coupled cluster theory with the complete basis set. This is the first time to gain a conclusive insight into the reaction mechanism and kinetics for this important reaction in detail. The reaction takes place via a chemical activation mechanism. The barrierless association of propionyl with oxygen produces the propionylperoxy radical, which decomposes to form the hydroxyl radical and the three-center alpha-lactone predominantly or the four-center beta-propiolactone. The oxidation of propionyl radical to carbon monoxide or carbon dioxide is not straightforward rather via the secondary decomposition of alpha-lactone and beta-propiolactone. Kinetically, the overall rate constant is almost pressure independent and it approaches the high-pressure limit around tens of torr of helium. At temperatures below 600 K, the rate constant shows negative temperature dependence. The experimental yields of the hydroxyl radical can be well reproduced, with the average energy transferred per collision -DeltaE=20-25 cm(-1) at 213 and 295 K (helium bath gas). At low pressures, together with the hydroxy radical, alpha-lactone is the major product, while beta-propiolactone only accounts for about one-fifth of alpha-lactone. At the high-pressure limit, the production of the propionylperoxy radical is dominant together with a fraction of the isomers. The infrared spectroscopy or the mass spectroscopy techniques are suggested to be employed in the future experimental study of the C2H5CO+O2 reaction.  相似文献   

14.
The synthesis of (2S)-2-benzyloxymethyl-3-(2-fluoro-4-methoxyphenyl)- propionic acid, (2S)-2-benzyloxymethyl-3-(2-fluoro-4-methylphenyl)propionic acid and (2S)-2-benzyl-oxymethyl-3-(2,4-dimethylphenyl)propionic acid has been achieved by TiCl4 mediated alkylation of the corresponding (4R)-4-benzyl-3-[3-(2-fluoro-4-methoxyphenyl-, 2-fluoro-4-methylphenyl-, 2,4- dimethylphenyl-)propionyl]-2-oxazolidinones, followed by hydrolysis of the chiral auxiliary. The stereochemistry of the alkylation reaction was confirmed by an X-ray crystal structure of (4R)-4-benzyl-3-[(2S)-2-benzyloxymethyl-3-(2- fluoro-4-methylphenyl)propionyl]-2-oxazolidinone.  相似文献   

15.
Chitosan has been modified by incorporating a cationic moiety N- (3-chloro 2-hydroxypropyl) trimethyl ammonium chloride (CHPTAC) onto its primary amine group in aqueous alkali medium. A series of modified chitosan copolymers (Chito-cat-1 to Chito-cat-5) was synthesized by varying the CHPTAC to chitosan ratio. The modified chitosan copolymers have been characterized by viscometry, elemental analysis, infrared spectroscopy (IR), thermal analysis and X-ray diffractometry. From the above investigations, it has been confirmed that the cationic moiety was successfully incorporated onto chitosan.  相似文献   

16.
A new class of dibenzo[b,j][1,10]phenanthrolines has been prepared. The synthon acridones were achieved in very good yield by a one-pot reaction of 2-amino-5-chloro or 2′-chloro/flouro-substituted benzophenones with 1,2-cyclohexanedione in the presence of freshly prepared Eaton’s reagent (phosphorus pentoxide–methanesulfonic acid) without solvent, through Friedländer synthesis. Then these intermediates were reacted with 2-amino-3,5-dibromobenzaldehyde to afford 1,3-dibromo-10-chloro-8-aryl-6,7-dihydrodibenzo[b,j][1,10]phenanthroline. Also an one-pot reaction between 2?mol of 2-amino-5-chloro aryl benzophenones with 1?mol of 1,2-cyclohexanedione to get 3,10-dichloro-5,8-diaryl-6,7-dihydrodibenzo[b,j][1,10]phenanthroline has also been reported. The newly synthesized structures of the compounds were deduced by spectroscopic techniques.  相似文献   

17.
三氯锗丙酰氯与(R)-四氢噻唑-2-硫酮-4-羧酸甲酯反应, 得到标题化合物1, [α]~D^2^0-89.40°。经水解得到取代丙酰四氢噻唑-2-硫酮-4-羧酸甲酯基锗倍半氧化物2, X射线衍射法测出标题化合物的晶体结构, 属于正交晶系, 晶胞参数: a=0.6192(1)nm,b=1.1147(4)nm,c=2.1796(8)nm, V=1.5045nm^3, Z=4, 空间群P2~12~12~1。分子中酰胺羰基C=O与C=S基团处于C(4)NC(3)键两侧呈反式。用MNDO分子轨道方法研究了该化合物的电子结构, 电荷和键序分布,前沿轨道性质,讨论了电子光谱性质。  相似文献   

18.
Under conditions of Meerwein reaction and anionarylation the aryldiazonium salts and itaconic acid form 2-chloro(thiocyanato)-2-benzylbutanedioic acids as the chloro- and thiocyianatoarylation products. The reaction is not accompanied by the decarboxylation process and other transformations affecting the carboxy groups of itaconic acid.  相似文献   

19.
以对羟基苯磺酸钠为原料,经2,2-二甲基丙酰氯缩合、与氯化亚砜反应而成4-(2,2-二甲基丙酰氧基)苯磺酰氯,再经与2-氨基苯甲酸缩合、与甘氨酸苄酯成酰胺、加氢脱去保护基团,最后与氢氧化钠成盐而合成了西维来司钠。  相似文献   

20.
The synthesis and structure-activity relationships of N-terminus modified renin inhibitors containing the homostatin analogue, (2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acid, are described. The compounds having a 3-alkyl (or aryl)sulfonylpropionyl residue at the N-terminus are found to be potent inhibitors which contain two amino acids. (2RS,4S,5S)-N-Isobutyl-5-[N-[(2S)-3-ethylsulfonyl-2-(1- naphthylmethyl)propionyl]-L-norleucyl]-amino-2-ethyl-4-hydroxy-7- methyloctanamide (20) has an IC50 of 0.5 nM against human plasma renin and the oral bioavailability of 20 is 0.73% in rats. Interaction between renin and the N-terminus of 1 and 20 is discussed in molecular modeling studies.  相似文献   

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