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1.
A various new dithi‐ocarbamides were synthesized from heterocyclic six‐membered 1,3‐dicarbonyl systems, such as 4‐hydroxy‐2,5‐pyranopyridines, 4‐hydroxy‐2‐pyridones, 4‐Hydroxy‐2‐quinolones, 4‐hydroxy‐coumarins, and 4‐hydroxy‐1‐methyl‐2‐quinolones. The dicarbonyl compounds in the presence of anhydrous potassium carbonate in dimethyformamide react with tetraalkylthiuram disulfides to yield 3‐dialkylaminothiocarbonylthio derivatives through a simple, convenient one‐pot reaction. The structures were confirmed by using IR, NMR, and elemental analysis.  相似文献   

2.
Bromination in acetic acid is favored at C‐8 in 5,7‐dimethoxy‐4‐naphthol when the C‐2 substituent is methyl carboxylate, whereas C‐1 is favored when the C‐2 substituent is either acetoxymethylene or methyl.  相似文献   

3.
2‐(1‐Aryl‐2‐methoxyethenyl)benzaldehydes 2 , obtained by successive treatment of 1‐(1‐aryl‐2‐methoxyethenyl)‐2‐bromobenzenes 1 with BuLi and 1‐formylpiperidine, were transformed to the corresponding phenylhydrazones 3 on treatment with PhNHNH2. When these hydrazones were allowed to react with conc. HBr, cyclization, followed by dehydrogenation with air occurred, furnished 3‐aryl‐2‐methoxyinden‐1‐one (Z)‐phenylhydrazones 4 .  相似文献   

4.
Ttrans‐3,5‐dihydroperoxy‐3,5‐dimethyl‐1,2‐dioxalane has been used as new, effective, solid, inexpensive and nontoxic oxidant for in situ generation of Br+ from HBr. This system has been applied as catalyst for synthesis of 2‐aryl‐1H‐benzothiazoles and 2‐aryl‐1‐arylmethyl‐1H‐benzimidazoles at room temperature in excellent yields and high purity.  相似文献   

5.
Thirteen new 2-alkylaminoimidazolones(4) wre rapidly synthesized by a new solution-phase parallel synthetic method,which includes aza-Wittig reaction of iminophosphorane(1) with aromatic isocyanate to give carbodi-imide(2) and subsequent reaction of 2 with various aliphatic primary amine in a parallel fashion.The products were confirmed by ^1H NMR,MS,IR and X-ray crystallographic analysis.The unusual selectivity of the cyclization was probably due to the deometry of the guanidine intermediate.  相似文献   

6.
《中国化学会会志》2003,50(2):273-278
Spiro[indole‐pyranoimidazoles] ( 5 ) and spiro[indole‐pyranobenzopyrans] ( 6 ) are readily synthesized in one step in 86–92 and 91–97% yields by the Michael condensation of 3‐dicyanomethylene‐2H‐indol‐2‐ones ( 2 ) with 1‐phenyl‐2‐thiohydantoin ( 3 ) and 4‐hydroxy‐2H‐1‐benzopyran‐2‐one ( 4 ), respectively, without using any catalyst under different reaction conditions (conventional heating and microwave irradiation using (a) polar solvents (b) neutral alumina/silica gel as inorganic solid support in solvent free conditions). 2 was synthesized in situ by the Knoevenagel condensation of indole‐2,3‐dione ( 1 ) and malononitrile in the absence of any catalyst. 100% conversion was observed in most cases on TLC which also showed the formation of a single product. The comparison between the various methods is established.  相似文献   

7.
The reaction of 4‐(4‐acetylamino/bromophenyl)‐4‐oxobut‐2‐enoic acids with carbon nucleophiles afforded Michael adducts depending on the type of nucleophilic reagents and medium (acidic or basic). The adducts 2 and 3 were used as key starting materials to synthesize some heterocyclic compounds, which include pyridazinone, furanone, 1,2‐oxazin‐5‐one, 1.2‐diazapine, pyrane, and hydroxyl pyridine derivatives. The Steric factor plays an important role in regioselectivity. The structure of newly synthesized compounds was elucidated by elemental analysis and spectroscopic data.  相似文献   

8.
1,2,3,4‐Tetrahydro‐4,6‐dimethyldibenzothiophene was prepared by coupling 2‐bromo‐3‐methylcyclohexanone with 2‐methylbenzenethiol and annulating the product with the aid of polyphosphoric acid. A mixture of 1,2,3,4‐tetrahydro‐4,6‐dimethyldibenzothiophene and 4,6‐dimethyldibenzothiophene was prepared by coupling 2‐bromo‐3‐methylcyclohex‐2‐en‐1‐one with 2‐methylbenzenethiol and annulating the product with the aid of polyphosphoric acid. 2‐Bromo‐3‐methylcyclohexanone was synthesized by conjugate addition of Me3Al to 2‐bromocyclohex‐2‐en‐1‐one with CuBr as catalyst and 2‐bromo‐3‐methylcyclohex‐2‐en‐1‐one by bromination? elimination of 3‐methylcyclohex‐2‐en‐1‐one. 1,2,3,4,4a,9b‐Hexahydro‐4,6‐dimethyldibenzothiophene was prepared by reduction of 1,2,3,4‐tetrahydro‐4,6‐dimethyldibenzothiophene with Zn and CF3COOH.  相似文献   

9.
Copper(I) halides with triphenyl phosphine and imidaozlidine‐2‐thiones (L ‐NMe, L ‐NEt, and L ‐NPh) in acetonitrile/methanol (or dichloromethane) yielded copper(I) mixed‐ligand complexes: mononuclear, namely, [CuCl(κ1‐S‐L ‐NMe)(PPh3)2] ( 1 ), [CuBr(κ1‐S‐L ‐NMe)(PPh3)2] ( 2 ), [CuBr(κ1‐S‐L ‐NEt)(PPh3)2] ( 5 ), [CuI(κ1‐S‐L ‐NEt)(PPh3)2] ( 6 ), [CuCl(κ1‐S‐L ‐NPh)(PPh3)2] ( 7 ), and [CuBr(κ1‐S‐L ‐NPh)(PPh3)2] ( 8 ), and dinuclear, [Cu21‐I)2(μ‐S‐L ‐NMe)2(PPh3)2] ( 3 ) and [Cu2(μ‐Cl)21‐S‐L ‐NEt)2(PPh3)2] ( 4 ). All complexes were characterized with analytical data, IR and NMR spectroscopy, and X‐ray crystallography. Complexes 2 – 4 , 7 , and 8 each formed crystals in the triclinic system with P$\bar{1}$ space group, whereas complexes 1 , 5 , and 6 crystallized in the monoclinic crystal system with space groups P21/c, C2/c, and P21/n, respectively. Complex 2 has shown two independent molecules, [(CuBr(κ1‐S‐L ‐NMe)(PPh3)2] and [CuBr(PPh3)2] in the unit cell. For X = Cl, the thio‐ligand bonded to metal as terminal in complex 4 , whereas for X = I it is sulfur‐bridged in complex 3 .  相似文献   

10.
With the purpose of searching for new biologically active compounds, a method of synthesis of new heterocyclic systems [3‐alkyl(aryl)‐2‐thioxo‐2,3‐dihydro‐1H‐benzofuro[3,2‐d]pyrimidin‐4(1H)‐ones] has been developed. The method is based on the interaction of ethyl 3‐isothiocyanato‐1‐benzofurane‐2‐carboxylate in 2‐propanol with amines in the presence of an equimolecular quantity of triethylamine.  相似文献   

11.
A simple and efficient method is described for the synthesis of new functionalized 2‐aminothiazoles, the 2‐aminothiazole‐4‐phenyl‐5‐acetamides 5, in 67–96% yields based on an application of the Hantzsch synthesis. The method involves the reaction of thiourea with 3‐benzoyl‐3‐bromo‐propionamides 4 prepared from the corresponding 3‐benzoylpropionamides 3. The tautomeric structure of the γ‐keto amides 3 and 6 is directly related to the present study, because 2‐aminothiazoles 5 are readily obtained from the corresponding open chain γ‐keto amides 3.  相似文献   

12.
The chemoselectivity in the reaction of 2‐diazo‐3‐oxo‐3‐phenylpropanal ( 1 ) with aldehydes and ketones in the presence of Et3N was investigated. The results indicate that 1 reacts with aromatic aldehydes with weak electron‐donating substituents and cyclic ketones under formation of 6‐phenyl‐4H‐1,3‐dioxin‐4‐one derivatives. However, it reacts with aromatic aldehydes with electron‐withdrawing substituents to yield 1,3‐diaryl‐3‐hydroxypropan‐1‐ones, accompanied by chalcone derivatives in some cases. It did not react with linear ketones, aliphatic aldehydes, and aromatic aldehydes with strong electron‐donating substituents. A mechanism for the formation of 1,3‐diaryl‐3‐hydroxypropan‐1‐ones and chalcone derivatives is proposed. We also tried to react 1 with other unsaturated compounds, including various olefins and nitriles, and cumulated unsaturated compounds, such as N,N′‐dialkylcarbodiimines, phenyl isocyanate, isothiocyanate, and CS2. Only with N,N′‐dialkylcarbodiimines, the expected cycloaddition took place.  相似文献   

13.
1‐Pyridin‐3‐yl‐3‐(2‐thienyl of 2‐furyl)prop‐2‐en‐1‐ones 1a , 1b reacted with 2‐cyanoethanethioamide 2 to afford the corresponding 4‐(thiophen‐2‐yl or furan‐2‐yl)‐6‐sulfanyl‐2,3′‐bipyridine‐5‐carbonitriles 3a , 3b . The synthetic potentiality of compounds 3a , 3b were investigated in the present study via their reactions with several active halogen containing compounds 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 5 , 5a , 5b . Our aim here is the synthesis of 4‐(2‐thienyl or 2‐furyl)‐6‐pyridin‐3‐ylthieno[2,3‐b]pyridin‐3‐amines 6a , 6b , 6c , 6d , 6e , 6g , 6h , 6i , 6j , 6k , 6l , 6m , 6n ,via 6‐(alkyl‐thio)‐4‐(2‐thienyl or 2‐furyl)‐2,3′‐bipyridine‐5‐carbonitriles 5a , 5b , 5c , 5d , 5e , 5i , 5j , 5k , 5l , 5m . The structures of all newly synthesized heterocyclic compounds were elucidated by considering the data of IR, 1H‐NMR, mass spectra, as well as that of elemental analyses. Anti‐cancer, anti‐Alzheimer, and anti‐COX‐2 activities were investigated for all the newly synthesized heterocyclic compounds.  相似文献   

14.
The study on syntheses of some N‐substituted‐N′‐[5‐methyl‐1‐(4‐chlorophenyl)‐1,2,3‐triazol‐4‐yl]‐urea 6a‐e and N‐substituted‐[5‐methyl‐1‐(4‐chlorophenyl)‐1,2,3‐triazol‐4‐yl]carbonyl amide 6f‐l derivatives were reported in this paper. The yielded products 6a‐l were confirmed by elemental analyses, NMR, MS and IR spectra.  相似文献   

15.
A. Ebenezer Martin 《合成通讯》2013,43(11):1778-1783
A novel method for the synthesis of 6,12‐dihydro‐2‐methylindolo[2,3‐b]carbazol‐6‐ones was developed from 1‐oxo‐2,3,4,9‐tetrahydro‐1H‐carbazol‐1‐one through methyl 6‐methyl‐2‐(1‐oxo‐2,3,4,9‐tetrahydro‐1H‐carbazol‐2‐yl)oxoacetate in good yields. This method provides an alternative path for the synthesis of this product using 2‐hydroxy methylene‐2,3,4,9‐tetrahydro‐1H‐carbazol‐1‐one.  相似文献   

16.
In our previous studies, caudatin‐2,6‐dideoxy‐3‐O‐methy‐β‐d‐ cymaropyranoside (CDMC) was for the first time isolated from Cynanchum auriculatum Royle ex Wightand and was reported to possess a wide range of biological activities. However, the routes and metabolites of CDMC produced by intestinal bacteria are not well understood. In this study, ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry (UPLC‐Q‐TOF‐MS) technique combined with MetabolynxTMsoftware was applied to analyze metabolites of CDMC by human intestinal bacteria. The incubated samples collected for 48 h in an anaerobic incubator and extracted with ethyl acetate were analyzed by UPLC‐Q‐TOF‐MS within 12 min. Eight metabolites were identified based on MS and MS/MS data. The results indicated that hydrolysis, hydrogenation, demethylation and hydroxylation were the major metabolic pathways of CDMC in vitro. Seven strains of bacteria including Bacillus sp. 46, Enterococcus sp. 30 and sp. 45, Escherichia sp. 49A, sp. 64, sp. 68 and sp. 75 were further identified using 16S rRNA gene sequencing owing to their relatively strong metabolic capacity toward CDMC. The present study provides important information about metabolic routes of CDMC and the roles of different intestinal bacteria in the metabolism of CDMC. Moreover, those metabolites might influence the biological effect of CDMC in vivo, which affects the clinical effects of this medicinal plant. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

17.
Aminomercuration/reduction sequence of δ-alkenylamines is a typical route to substituted pyrrolidines. Backward reaction to the starting material is a major drawback which occurs during sodium borohydride reduction of the intermediate organomercurial. We describe here a new reduction procedure which prevents almost completely this backward reaction and leads to significant increases in the yields of pyrrolidines.  相似文献   

18.
An effective route to novel 4‐(alkylamino)‐1‐(arylsulfonyl)‐3‐benzoyl‐1,5‐dihydro‐5‐hydroxy‐5‐phenyl‐2H‐pyrrol‐2‐ones 10 is described (Scheme 2). This involves the reaction of an enamine, derived from the addition of a primary amine 5 to 1,4‐diphenylbut‐2‐yne‐1,4‐dione, with an arenesulfonyl isocyanate 7 . Some of these pyrrolones 10 exhibit a dynamic NMR behavior in solution because of restricted rotation around the C? N bond resulting from conjugation of the side‐chain N‐atom with the adjacent α,β‐unsaturated ketone group, and two rotamers are in equilibrium with each other in solution ( 10 ? 11 ; Scheme 3). The structures of the highly functionalized compounds 10 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS), by elemental analyses, and, in the case of 10a , by X‐ray crystallography. A plausible mechanism for the reaction is proposed (Scheme 4).  相似文献   

19.
Anionic polymerizations of three 1,3‐butadiene derivatives containing different N,N‐dialkyl amide functions, N,N‐diisopropylamide (DiPA), piperidineamide (PiA), and cis‐2,6‐dimethylpiperidineamide (DMPA) were performed under various conditions, and their polymerization behavior was compared with that of N,N‐diethylamide analogue (DEA), which was previously reported. When polymerization of DiPA was performed at ?78 °C with potassium counter ion, only trace amounts of oligomers were formed, whereas polymers with a narrow molecular weight distribution were obtained in moderate yield when DiPA was polymerized at 0 °C in the presence of LiCl. Decrease in molecular weight and broadening of molecular weight distribution were observed when polymerization was performed at a higher temperature of 20 °C, presumably because of the effect of ceiling temperature. In the case of DMPA, no polymer was formed at 0 °C and polymers with relatively broad molecular weight distributions (Mw/Mn = 1.2) were obtained at 20 °C. The polymerization rate of PiA was much faster than that of the other monomers, and poly(PiA) was obtained in high yield even at ?78 °C in 24 h. The microstructure of the resulting polymers were exclusively 1,4‐ for poly(DMPA), whereas 20–30% of the 1,2‐structure was contained in poly(DiPA) and poly(PiA). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3714–3721, 2010  相似文献   

20.
α‐Chloroformylarylhydrazones 1 and α‐chloroformylarylhydrazones of sydnonecarbaldehydes 3 have been prepared by a new synthetic route: α‐chloroformylarylhydrazines hydrochlorides 2 reacted with corresponding carbonyl compounds. Reactions of compounds 3 with various hydrazines to give 6‐sydnonyl‐1,2,4,5‐tetrazinan‐3‐ones 7 and/or carbazones 8 were also investigated. By oxidization with lead dioxide, compounds 7 were trans formed to stable 6‐sydnonyl‐3,4‐dihydro‐3‐oxo‐1,2,4,5‐tetrazin‐1(2H)‐yl radical derivatives 9 (sydnonyl verdazyls). Furthermore, sydnonecarbaldehydes arylhydrazones 5 through acidic conditions could be transferred to 4‐arylamino‐1,2,3‐triazoles 6 which were also obtained by means of acidic decompositions of 4‐formylsydnones 10 .  相似文献   

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