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1.
Ethyl 1-oxaspiro[2,5]octane-2-carboxylate reacts with diethyl sodiomalonate in toluene to give diethyl 2-oxo-1-oxaspiro[4,5]decane-3,4-dicarboxylate, which on distillation under goes partial de-ethoxycarbonylation to give ethyl 2-oxo-1-oxaspiro[4,5]decane-4-carboxylate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 28–32, January, 1991.  相似文献   

2.
Dimethyl thiazolidine-2,4-dicarboxylate 2 and ethyl l-thia-4-azaspiro[4.5]decane-3-carboxylates 3-5 were obtained as a diastereoisomeric mixture while their 3-aminoacetyl derivatives were isolated in only one isomeric form. These reactions of N-acylation were stereoselective, which can be explained by an interconversion of the diastereoisomers via a seco intermediate. The 1H nmr analysis of amides 6 and 11 exhibited the presence of both cis and trans amide bond conformations, whereas only one cis conformation was observed for spiro amides 8-10 and 13-15.  相似文献   

3.
An efficient method has been developed for the synthesis of a novel β-keto ester-containing pyranoquinoline compound, i.e., ethyl 4-oxo-3,4-dihydro-1H-pyrano[3,4-b]quinoline-3-carboxylate. The method entails a two-step synthesis. The first step involves the Williamson-type reaction of ethyl 2-bromomethyl-3-quinoline-3-carboxylate with ethyl hydroxyacetate in anhydrous benzene to afford the intermediate ethyl 2-[(2-ethoxy-2-oxoethoxy)methyl]quinoline-3-carboxylate. The second step includes the Dieckmann condensation reaction of the resulting intermediate in the presence of sodium ethoxide in anhydrous toluene to afford the desired pyranoquinoline containing β-keto ester moiety. Keto-enol tautomerism of the compound thus obtained was investigated by spectroscopic methods.  相似文献   

4.
An improved method for the preparation and purification of ethyl 2-hydroxy-4-oxo-4H-pyrido[1,2-a]-pyrimidine-3-carboxylates is proposed. According to 1H and 13C NMR spectroscopic data the synthesized compounds exist in DMSO solution in the 2-hydroxy-4-oxo form while in the crystal (at least for the case of the unsubstituted derivative) X-ray analysis shows that it occurs in the bipolar 2,4-dioxo form. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 864–876, June, 2007.  相似文献   

5.
300th Anniversary of the Reunification of the Ukraine with Russia Dnepropetrovsk State University, Dnepropetrovsk 320010. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, p. 854, June, 1991.  相似文献   

6.
7.
The synthesis of a Δ1-carbapenem and two β-lactams possessing a Br-atom at the N-substituting center not involved in the lactam ring and bearing the carboxyl group is described. The β-lactams having this kind of Br-substitution are more susceptible to nucleophilic attack than those having a conjugated double bond with the N-atom of the β-lactam ring. DBU is found to be an excellent reagent for the elimination of the silyloxy function. Moreover, a simple method for the addition of diethyl phosphite to an α, β-unsaturated double bond using a catalytic amount of NaH is described.  相似文献   

8.
The preparation of 3-amino- and 3-dialkylamino-4-cyanoazepino[3,4-fc]indoles bearing substituents on the aromatic nucleus and N10 is outlined. Starting from suitable substituted ethyl 3-formylindole-2-carboxy-latcs 2 , condensation with malononitrile ( 3 ) and subsequent sodium borohydride-reduction yielded ethyl 3-(2,2-dicyanoethyl)indole-2-carboxylates 5 and 19 , respectively, which were cyclized in boiling alkoxides to 3-alkoxy-4-cyanoazepino[3,4-b]indoles 10,11,20 and 21 . This sequence constitutes a novel and flexible route to functional azepino[3,4-b>]indoles. The aminolysis of 10,11,20 and 21 with different amines and ammonia yielded the title compounds which were screened for their possible biological activity.  相似文献   

9.
The reactions of 3-acetyl-4-ethoxycarbonyl- or 3,4-diethoxycarbonylpyrrolo[1,2-a]pyrimidine derivatives 7a,b , which were prepared by condensation of the 2-aminopyrrole ( 4 ) with ethyl 3-ethoxymethylene-2,4-dioxovalerate ( 5a ) or ethyl ethoxymethyleneoxaloacetate ( 5b ), with diazomethane are described. Thus, reaction of 7a , with diazomethane gave ethyl 2a-acetyl-7-cyano-2a,3a-dihydro-5,6-dimethyl-3H -cyclopropa[e]pyrrolo[1,2-a]pyrimidine-3a-carboxylate ( 11 ) in 74% yield, which was readily transformed into the 1-pyrrol-2-yl-pyrrole ( 18 ) by treatment with potassium hydroxide. On the other hand, reaction of 7b with diazomethane afforded three products whose structures were assigned as diethyl 7-cyano-2a,3a-dihydro-5,6-dimethyl-3H-cyclopropa[e]pyrrolo[1,2-a]pyrimidine-2a,3a-carboxylate ( 20 ), 6-cyano-7,8-dimethyl-3a,3b,5,9a-tetrahydro-4H -aziridino[c]-1H or 3H-pyrazolo[3,4-e]pyrrolo[1,2-a]pyrimidine-3a,9a-dicarboxylates ( 21,22 ). Ring Transformation of 20 to 25 was not observed.  相似文献   

10.
The dissociation constants of 1-oxo-4-hydroxypyridazino[4,5-b]quinoxaline were measured by potentiometric titration. It is shown that this compound is a dibasic acid. Its reaction with organic bases, acids, alkalis, and oxidizing agents was studied. Its aminomethylation, hydroxymethylation, and cyanoethylation were also investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 402–406, March, 1977.  相似文献   

11.
The title compound mesityl acetic acid 3-mesityl-2-oxo-1-oxaspiro[4,4]non-3-en-4-yl ester (5, C28H32O4, Mr = 432.56), as a spiromesifen derivative, has been synthesized by the conden- sation reaction of 2,4,6-trimethylphenylacetic chloride with 4-hydroxyl-3-mesityl-1-oxa-spiro[4,4]- non-3-en-2-one (4), and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9261(7), b = 8.2802(8), c = 18.7604(18) , α = 91.576(3), β = 93.277(2), γ = 95.306(12)o, V = 1223.3(2) 3, Z = 2, Dc = 1.174 g/cm3, F(000) = 464, μ = 0.077 mm-1, S = 1.001, the final R = 0.0624 and wR = 0.1415 for 2809 observed reflections with I 2σ(I) and 290 variable parameters. The crystal analysis results show that the five-membered cyclopentyl ring displays an envelope conformation with C(25) atom at the flap position, 0.537(3)  out of the mean plane formed by the other four atoms. The dihedral angles between the two benzene and furan rings are 70.0(2) and 80.67(3)o, respectively.  相似文献   

12.
The three-component reaction of 4-hydroxy-1-methyl-2(1H)-quinolinone, aromatic aldehydes and ethyl cyanoacetate was carried out in the presence of a catalytic amount of 4-dimethyl aminopyridine(DMAP) in aqueous ethanol. The reactions result in the formation of pyranoquinoline derivatives in excellent yields. Antibacterial activity has been evaluated against Gram positive and Gram negative bacteria for some of the synthesized compounds. The results indicated that these compounds are moderately effective against bacterial growth and their effectiveness is highest against Pseudomonas aeruginosa.  相似文献   

13.
Reaction of 5-phenyl-2,3-dihydro-2,3-furandione with ethyl 3-benzylamino-2-butenoate, resulting in ethyl 1-benzyl-2-hydroxy-5-methyl-3-oxo-2-phenacyl-2,3-dihydropyrrole-4-carboxylate and benzylamide ofN-benzoylpyruvic acid, was studied. The structure of the pyrrole derivative was confirmed by X-ray analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1552–1555, August, 1995.  相似文献   

14.
Drury Caine  Chia-Rong Lin 《合成通讯》2013,43(17):2473-2476
The allylic lactone 1 was prepared from the reaction of lithium 3-lithiopropanoate (5) with isophorone (3) followed by mild acid treatment of the hydroxy acid adduct.  相似文献   

15.
《Tetrahedron letters》1986,27(49):6001-6004
Lead tetraacetate oxidation of the carbapenem derived ethanethiol adducts (4–6) gave the corresponding 3-acetoxy-3-ethylthio derivatives (7–9). Oxidation to sulphone and elimination of ethylsulphinic acid furnished the 3-acetoxy-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate ester (12). Alternatively, elimination of acetic acid from (7) and (8) provided a new route to alkylthiocarbapenems.  相似文献   

16.
林振光  庄鸿辉 《结构化学》1996,15(3):199-204
环己酮与硫代碳酰肼在不同介质中的反应,合成出两个不同的环己烷螺含氮杂环化合物。经X-射线结构分析确定它们分别为1,2,4,5-四氮螺[5,5]十一烷-3-硫酮,C_7H_(14)N_4S(Ⅰ)和1,2,4,-三氮螺[4,5]癸-1-烯-4-氨基-3-硫酮。C_7H_(12)N_4S_x(S_x=0.8S+0.2O)(Ⅱ)。晶体学参数分别为(Ⅰ):P2_1/c,a=12.026(4),b=26.817(6),c=12.042(3),β=115.94(2)°,Z=4,V=933.4(10),M_r=186.28;(Ⅱ):P2_1/m,a=6.595(7),b=6.817(6),c=10.572(6),β=106.3(1)°,V=456(1),Z=2,M_r=181.05。最终一致因子分别为R=0.054,R_w=0.065和R=0.089,R_w=0.096。两个化合物中,环己烷都为椅式构型,它与其螺联的6员氮杂环,5员氮杂环的最小二乘平面间的夹角分别为68.94和90°。并对合成反应途径作了初步讨论。  相似文献   

17.
4,6-Dimethyl-2H-thieno[2,3-b]pyridin-3-one reacts with 2-aryl-1,1-dicyanoethylenes or an aromatic aldehyde/ketone (cyclohexanone and piperidone derivatives) and malononitrile to give substituted 2-amino-3-cyano-7,9-dimethyl-4H-pyrano[2",3":4,5]thieno[2,3-b]pyridines.  相似文献   

18.
Condensation of O-phenylhydroxylamine with 1H-2,3,4,5,6,7-hexahydroazepine-2,4-dione in alcoholic hydrogen chloride solution gave 1-oxo-1H-2,3,4,5-tetrahydrobenzofuro[3,2-c]-azepine, while a similar condensation with 6,6-dimethyl-1H-2,3,4,5,6,7-hexahydroazepine-2,4-dione gave a mixture of 4,4-dimethyl-1H-2,3,4,5-tetrahydrobenzofuro[3,2-c]azepine and 2-oxo-3-(3,3-dimethyl-5-pyrrolidylidene)benzofuran. Tetrahydrobenzofuroazepines were also synthesized by Beckmann rearrangement of oximes of 1-oxo-1,2,3,4-tetrahydrobenzofuran and 3,3-dimethyl-1-oxo-1,2,3,4-tetrahydrodibenzofuran, which were obtained in turn by condensation of O-phenylhydroxylamine with dihydroresorcinol and dimedone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 149–153, February, 1973.  相似文献   

19.
A number of 1-aryl-2-oxo-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole 4-oxides were synthesized based on 3-[N-aryl-N-(chloroacetyl)amino]-2-formylindoles. The nature of the substituent in the 1-aryl fragment has a pronounced influence on the course of reactions throughout the whole sequence of transformations during the synthesis of diazepinoindoles. The reduction of 4-oxides by formamidinosulfinic acid, hydrogen in the presence of Pd/C, and sodium bisulfite was studied. The structures of the reaction products were confirmed using IR and 1H NMR spectroscopy and mass spectrometry.  相似文献   

20.
The methylation of 1-oxo-4-hydroxypyridazino[4,5-b]quinoxaline (I) with methyl iodide and diazomethane under various conditions was studied. The structures of the disodium and disilver salts of I were established by means of spectrophotometric methods of analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1418–1420, October, 1973.  相似文献   

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