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1.
Conclusions N-Vinyloxyethylated amides were synthesized by reacting the vinyl ethers of amino and ketimino alcohols with the acid chlorides of the 2,4-dichlorophenoxyacetic, o-, and p- chlorobenzoic acids, while the previously unknown N-vinyloxyethylated derivatives of ureas were obtained from the vinyl ethers of amino alcohols and aryl isocyanates.Translated fron Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1893–1896, August, 1981.  相似文献   

2.
High molecular-weight aromatic polyamides were obtained from 1,5- and 2,6-bis-(4′-carboxy-4-phenylenoxy-sulfonyl)naphthalene by direct polycondensation reaction in N-methyl-2-pyrrolidone with various aromatic diamines, using triphenyl phosphite and pyridine as condensing agents. The polymers were characterized by elemental analysis, thermogravimetric analysis, differential scanning calorimetry, and infrared analysis. The polyamides, obtained in quantitative yield, possessed inherent viscosities in the range 0.42–1.70 dL/g, glass transition temperatures between 245–310°C, and 10% weight loss temperatures in nitrogen and air above 435 and 424°C, respectively. Most of the polymers were soluble in aprotic solvents. The effect of the structure on properties, such as solubility, Tg, and thermal behavior, were also studied. © 1996 John Wiley & Sons, Inc.  相似文献   

3.
Vinylogy is a widely accepted principle involving the transfer of electronic chemical character through a double bond, and many reactions have been developed by applying this concept. In contrast, phenylogy, which involves the connection of two substituents through a benzene ring, is rarely recognized as a related idea. In this article, we present synthesis and physical properties, including their structure and reactivity of phenylogous amides. This amide mimetic unit is relatively stable and easily prepared by the Hartwig–Buchwald amination reaction. The effect of the resonance was examined by means of crystallography, reactivity and UV–vis spectroscopy.  相似文献   

4.
5.
《Supramolecular Science》1995,2(2):117-123
The synthesis of new fluorine-containing double-chain surfactants from di- and tri-substituted ureas is described; the vesicle-forming behavior is investigated for some surfactants. Under bath sonication mixed-chain surfactants form spherical unilamellar vesicles, while surfactants possessing two perfluoroaklylated segments give polydispersed vesicle populations.  相似文献   

6.
Trost BM  Stiles DT 《Organic letters》2005,7(11):2117-2120
[reaction: see text]. A variety of N-substituted allenes have been synthesized by the copper-catalyzed coupling reaction between allenyl halides and amides, carbamates, and ureas. The reactions proceed in good to excellent yield using 7 mol % copper thiophenecarboxylate and 15 mol % of a diamine catalyst.  相似文献   

7.
Amides of betulonic and oleanonic acids with diethylenetriamine, triethylenetetramine, and spermidine were synthesized. Antitumor activity in vitro was not found for the conjugate of betulonic acid with diethylenetriamine.  相似文献   

8.
董彬  张珍仙  刘亚飞  张彰 《化学研究》2014,25(6):627-631
合成了一类含季铵基和磺酸基结构的非对称Gemini两性离子表面活性剂;利用红外光谱、质谱、离子定性试验验证了合成产物的分子结构,并测定了其表面性质.结果表明,目标产物的分子结构符合设计预期;五种非对称Gemini两性离子表面活性剂的表面张力在30mN/m左右,临界胶束浓度达到10-4~10-5数量级.此外,虽然非对称Gemini两性离子表面活性剂的起泡性能比相应单链型表面活性剂的稍差,但其稳泡性明显优于后者.  相似文献   

9.
[reaction: see text] An efficient one-step amination of cyclic amides and ureas has been developed. Treatment of cyclic amides and cyclic ureas with BOP in the presence of DBU in various solvents led to the formation of cyclic amidines and cyclic guanidines in good to excellent yields. Concise syntheses of biologically intriguing kinetin and potent kinase inhibitor olomoucin were thus achieved in just one and two steps, respectively.  相似文献   

10.
The synthesis of deoxythioformamido and deoxythioacetamido derivatives of 1,2:3,4-di-O-isopropylidene--D-galactopyranose, 1,2:3,5-di-O-isopropylidene--D-glucofuranose, and 2,3:4,5-di-O-isopropylidene-β-D-fructopyranose at the primary carbon atom has been effected by thionation of the corresponding sugar amides. Formamides and thioformamides existed as a mixture of the Z (major) and E (minor) stereomers around the N---C(=X) bond in CDCl3 solutions, while the Z rotamer was the sole one detected in the cases of acetamides and thioacelamides.  相似文献   

11.
Oligoribonucleotide analogues having amide internucleoside linkages (AM1: 3'-CH(2)CONH-5' and AM2: 3'-CH(2)NHCO-5') at selected positions have been synthesized and the thermal stability of duplexes formed by these analogues with complementary RNA fragments has been evaluated by UV melting experiments. Two series of oligomers with either 2'-OH or 2'-OMe vicinal to the amide linkages were studied. Monomeric synthons (3' and 5'-C amines and carboxylic acids) were synthesized as follows: For synthesis of the AM1 analogue, the known sequence of radical allylation followed by the cleavage of the double bond was adopted. For synthesis of the AM2 analogue, novel routes via addition of nitromethane followed by conversion of the nitro function to either amino or carboxyl groups were developed. Coupling of monomeric amines and carboxylic acids followed by protecting group manipulation and phosphonylation gave dimeric 3'-hydrogenphosphonate building blocks for oligonucleotide synthesis. Monomeric model compounds having 3'-amide and 2'-OH or 2'-OMe groups were also prepared and their conformational equilibrium was determined by (1)H NMR. The AM1 and AM2 models showed equal preferences for the North conformers (at 40 degrees C, 88-89% with 2'-OH, and 92-93% with 2'-OMe). At physiological salt concentration (0.1 M NaCl) the duplexes between AM1 modified oligonucleotides and RNA had stability similar to unmodified RNA-RNA duplexes (Delta t(m)= -0.2 to +0.7 degrees C per modification). However, the AM2 modification resulted in substantial stabilization of duplexes: Delta t(m)= +1 to +2.4 degrees C per modification compared to all RNA. A 2'-O-methyl vicinal to the AM2 linkage further increased the duplex stability. Our results suggest that RNA analogues having amide internucleoside bonds are very promising candidates for medicinal applications.  相似文献   

12.
Synthetic methods for cephalosporin G derivatized at the carboxyl were developed. Dinitroglycerine, acetoxymethyl, and choline esters of cephalosporin G and its amide in addition to amides of cephalosporin G with glutamic acid and arginine were synthesized. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 85–88, January–February, 2007.  相似文献   

13.
Sang-Hyuep Lee  Kim D Janda 《Tetrahedron》2004,60(15):3439-3443
The conversion of carbamates into ureas using aluminum amide complexes is reported. This reaction is a convenient method to prepare bi-, tri- and tetra-substituted ureas from carbamate-protected primary or secondary amines by reaction with primary or secondary amines in the presence of stoichometric quantities of trimethylaluminum. A reactivity trend of the various carbamates was observed and methyl and benzyl carbamates were reacted selectively in the presence of t-butyl carbamates.  相似文献   

14.
Two novel ferrocenylphenyl-containing amides have been synthesized by reaction of ferrocenylbencarboxylchloride and 1, 2-di-(o_aminophenoxy)ethane. A single crystal X-ray analysis shows that compound 3 crystallizes in the triclinic system, space group P-1, and compound 4 crystallizes in orthorhombic system, space group Pca21. There are intramolecular H-bonds in both the compounds, two H-bonds in compound 3 and one in compound 4. The dihedral angels of Cp-ring and phenyl ring range from 3.8° to 20.8°. Translated from Chemical Research and Application, 2006, 18(2) (in Chinese)  相似文献   

15.
Two new ferrocene derivatives with amide linkages were synthesized by the condensation of 4-ferrocenylaniline with n-alkyl acid chloride derivatives as pristine orange solids in good yields. FTIR and 1H/13C NMR studies have confirmed the basic structure of the molecules with the involvement of intermolecular H-bonding, which together with the ferrocene-like packing ensures the stability of the crystal structure. Crystal structures for both compounds were solved by Rietveld refinements of high resolution X-ray powder diffraction data. The XRD results show that both compounds crystallize in the monoclinic space group P21/c. The primary feature of the crystal structure is a double layer of ferrocenyl groups stretched out in the b-c -plane perpendicular to the a-axis, with packing of the ferrocenyl groups occurring in a manner similar to that of pure ferrocene. Despite the close structural similarity, both compounds differ in the optimized geometry of respective Ferrocene conformers. The Cp rings are eclipsed for one Ferrocene conformer and close to staggered for the other, owing to the low energy barrier for the rotation of a cyclopentadienyl ring relative to the rest of the molecule.  相似文献   

16.
The interfacial dilational viscoelastic properties of two demulsifiers with straight chain (SP-169) and branched chain (AE-121) at the oil-water interfaces were investigated by means of the longitudinal waves method and the interfacial tension relaxation method, respectively. The results obtained by the longitudinal waves method showed that the dilational viscous component for AE-121 and SP-169 also passed through a maximum value with increasing concentration. It was found that the maximum value appeared at different demulsifier concentrations during our experiment frequency; and the higher is the dilational frequency, the lower is the concentration. The influences of AE-121 and SP-169 on the dilational viscoelastic properties of the oil-water interface containing surface-active fraction from Iranian crude oil have been measured. The results clearly stated that both demulsifiers could obviously decrease the dilational elasticity of oil-water interface containing surface-active fraction. At low concentration, because of stronger adsorption ability, SP-169 has stronger ability to decreasing the dilational modulus than AE-121. We also found that the dilational modulus of the interface contained surface-active fraction passed through a minimum value with increasing demulsifier concentration for both demulsifiers. This result indicated the dosage of demulsifier had an optimum value. The results obtained by means of interfacial tension relaxation method showed that the slow relaxation processes involve mainly rearrangement in the conformation of the molecules appeared with increasing demulsifier concentration.  相似文献   

17.
1,3-Bis[(triethoxysilyl)methyl]tetrahydropyrimidin-2-one and 1,3-bis[(dimethoxysilyl)methyl]tetrahydro-pyrimidin-2-one have been synthesized on interacting urea with N,N′-bis(silylmethyl)propylenamines (EtO)3−nMenSiCH2NH(CH2)3NHCH2SiMen(OEt)3−n (n = 0, 2). Their interaction with boron trichloride has been studied. The structures of all the compounds synthesized have been demonstrated by multinuclear NMR spectroscopy. Dedicated to the 50th Anniversary of the Latvian Institute of Organic Synthesis __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 238–244, February, 2007.  相似文献   

18.
Summary It was shown that isomerization of alkenes with displacement of the double bond and hydrogen exchange in ] hydrocarbons both belong to the class of acid-base reactions; they are catalyzed by amide ions in ammoniacal solutions and by solid amides under heterogeneous conditions.  相似文献   

19.
20.
非对称取代脲的合成与应用   总被引:14,自引:0,他引:14  
总结了合成非对称取代脲的几种方法,分析了各种方法的利弊,介绍了非对称 取代脲的主要应用,指出直接利用一氧化碳进行硒催化的胺与硝基化合物的氧化还 原羰基化反应来合成非对称取代脲的方法是比较有发展前景的方法,并对硒催化的 氧化还原羰基化反应作了较为详细的介绍。  相似文献   

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