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1.
Although the reactions of ketenes and three-membered heterocycles containing one hetero atom are well known,1,2 only one investigation of similar recations with three-membered rings containing two hetero atoms has been reported.3 The reaction of 2-ethyl-3-phenyloxaziridine with diphenylketene was found to afford among other minor products an oxazolidinone derivative (1) and benzaldehyde in yields of 38% and 50% respectively. 相似文献
2.
An investigation was made into the opening of the epoxide ring of piperidine-4-spiro-2-oxiranes by N-, H-, C-, and P-nucleophiles, which yielded the corresponding 3,4-dihydroxy- and 3-hydroxypiperidine derivatives. When these epoxides were reacted with organomagnesium compounds, regrouping occurred, the piperidine ring reducing in size to a pyrrolidine ring and the latter being functionalized by a hydroxymethyl group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1499–1503, November, 1993. 相似文献
3.
A. Ya. Strakov M. V. Petrova A. I. Gurkovskii O. Ya. Neiland 《Chemistry of Heterocyclic Compounds》1999,35(3):286-289
Reaction of 2-formyldimedone and 2-formyl-1,3-indanedione with 1,1-di(2-hydroxyethylamino)- and 1,1-di(4-morpholyl)-2-nitroethylenes produces 2-[3,3-di(2-hydroxyethylamino)-2-nitroprop-2-en-1-ylidene]- and 2-[3,3-di(4-morpholyl)-2-nitroprop-2-en-1-ylidene]-5,5-dimethyl-1,3-cyclohexanediones and the 1,3-indanediones, respectively. The reaction of the same 2-formyl-1,3-cyclanediones with 2-nitromethyleneimidazolidine yields 8,8-dimethyl-4-nitro-6-oxo-1,2,3,6,7,8-hexahydroimidazo[1,2-a]quinoline and 4-nitro-6-oxo-1,2-dihydro-6H-imidazo[1,2-c]-4-azafluorene.Riga Technical University, Riga LV-1658, Latvia; e-mail: marina@osi.lanet.lv. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 330–333, March, 1999. 相似文献
4.
《合成通讯》2013,43(17):3071-3076
Abstract The treatment of 4-(2′-hydroxyaryl)-2-(N,N-dialkylamino)-1,3-dithiolium perchlorates (1a–g) with sodium sulfide nonahydrate in ethanol at room temperature affords the corresponding 1,3-dithiole-2-thiones (2a–g). When these reactions are conducted in boiling ethanol, 2′-hydroxyacetophenones (3a–g) have been obtained in good to excellent yield. A tentative mechanism for the formation of 3a–g shows that this reaction is regioselective, this being established by the presence of hydroxyl group in 2′-position. That has been confirmed in a control experiment, 4-phenyl-2-(piperidin-1-yl)-1,3-dithiolium perchlorate affording a mixture of condensation products of acetophenone and phenylacetaldehyde, under similar reaction conditions. 相似文献
5.
邻羟基二苯甲酰基甲烷与Ac2O和HC(OEt)3反应通常是HC(OEt)3作为酰化剂,得到3-苯甲酰基色酮。本文报道5-甲氧羰基-2-羟基苯甲酰基-(2′-甲氧苯甲酰基)甲烷与Ac2O和HC(OEt)3反应时,是Ac2O而不是HC(OEt)3作为酰化剂,生成3-苯甲酰基-2-甲基色酮。其结构经NMR、MS、IR和EA证实。并对其反应机理作了讨论。 相似文献
6.
Augusto Rivera Juan Francisco León Jasmin Rivera Eva Cecilia Parra Jindra Purmova Eleuterio Burgueño-Tapia 《合成通讯》2013,43(11):2029-2040
A one-step synthesis of 2t-substituted-1r,3c-bis(2′-hydroxy-5′- substituted-benzyl)-imidazolidines from 1,3-bis(2′-hydroxy-5′-substituted-benzyl)-imidazolidines and aromatic aldehydes is reported. The relative stereochemistry of the five-membered ring was evident from 1H NMR measurements combined with MMX calculations. 相似文献
7.
5,5′-Dialkyl-6,6′-dichloro-2,2′-bipyridines were synthesized starting from 3-substituted 2-chloro-6-iodopyridines using Pd-catalyzed coupling conditions. 6-Alkyl-3,5-dichloro-2H-1,4-oxazin-2-ones were excellent precursors for the synthesis of these functionalized 2-iodo-6-chloropyridines. 相似文献
8.
M. J. Maślankiewicz M. Rudnik A. Maślankiewicz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2481-2490
Reaction of 4-methoxy-3'-alkylthio-3,4'-diquinolinyl sulfides 1a-d with a nitrating mixture led to the title sulfoxides 2a-d , but the same treatment of isopropylthio derivative 1e resulted in S-dealkylation and oxidation with formation of 3,3'-diquinolinyl disulfide 3 . 3'-Alkylsulfinyl group promotes nucleophilic methoxy-desulfidation of 4'-quinolinyl sulfur bond in sulfoxides 2 , as compared to that in sulfides 1 , in which case it leads to 3-quinolinyl sulfoxides 6 and 3-quinolinethiolate 4-A . 相似文献
9.
C. R. Noe H. -P. Buchstaller G. Haberhauer A. Holzner 《Monatshefte für Chemie / Chemical Monthly》1997,128(5):509-527
Zusammenfassung Die Synthese von geschützten 2,3-Dideoxy-2-hydroxymethyl-nucleosiden wird beschrieben. Die durch ein Mehrstufenverfahren aus Isopropylidenglycerol erhaltenen Nucleoside können als Bausteine zur Darstellung von Oligonucleotiden verwendet werden, deren 2- und 5-Positionen über eine Etherbrücke verbunden sind.
Synthesis of 2,3-dideoxy-2-hydroxymethyl nucleosides
Summary The synthesis of protected 2,3-dideoxy-2-hydroxymethyl nucleosides is presented. The nucleosides, obtained in a multi-step procedure starting from isopropylideneglycerol, may be used as building blocks for the synthesis of 2,5-ether linked oligonucleotides.相似文献
10.
A. V. Aksenov A. V. Sarapy Yu. I. Smushkevich 《Chemistry of Heterocyclic Compounds》2000,36(8):952-955
The 1,4-dihydro-2,3-biquinolyl reacts with organolithium compounds to form the mixture of 4-R-1,4-dihydro-2,3-biquinolyls and 2-R-1,2-dihydro-2,3-biquinolyls in the ratio analogous to the conversion in the series of 2,3-biquinolyl. The utilization of the complex, the organolithium compound-TMEDA, in this process leads, after treatment of the reaction mixture with water, exclusively to 2-R-1,2-dihydro-2,3-biquinolyls. Treatment with methyl iodide leads to 1-methyl-2-R-1,2-dihydro-2,3-biquinolyls. 相似文献
11.
A. Okruszek P. Guga Wojciech J. Stbc 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract It has been recently demonstrated in our laboratory CD that ribonucleoside cyclic 3′,5′-phosphorothioates react with epoxides to give as a major product corresponding cyclic 5′,3′-phosphates, We now report the results OF our ste-reochemical studies OF this reaction. WE have Found that the diastereomerically pure (Sp) 3′.5′-CUFLPS when treated with styrene [10O]-oxide in ethanol gives the same isotopomer OF 2′,3′-[10O]cUMP as that obtained From the reaction of endo-2′.3′-cUMPS with styrene [10O]-oxide. This result strongly supports our previous assumption that reaction of 3′,5′-cNMPS with epoxides proceeds via 3′-oxathiaphosphorylated intermediate (L) which is Formed with inversion and decomposes to 2′,3′-cNMP with retention of configuration at phosphorus atom. 相似文献
12.
A. L. Kurlovich V. A. Tarasevich N. G. Kozlov 《Russian Journal of Organic Chemistry》2009,45(10):1503-1508
Condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and cyclohexane-1,3-dione, methyl
2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone gave the corresponding 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydro-12H-benzo[c]acridin-8-ones. The reaction of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and indan-1,3-dione
produced 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-8H-benzo[h]indeno[1,2-b]quinolin-8-one. 7-(2′-Hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydrobenzo[b][1,10]phenanthrolin-8-ones were obtained by three-component condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde
with quinolin-8-amine and cyclohexane-1,3-dione, methyl 2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone. 相似文献
13.
Pavla Perlíková Neus Jornet Martínez Lenka Slavětínská Michal Hocek 《Tetrahedron》2012,68(39):8300-8310
A series of novel sugar-modified derivatives of cytostatic 6-hetaryl-7-deazapurine ribonucleosides (2′-deoxy-2′-fluororibo- and 2′-deoxy-2′,2-difluororibonucleosides) bearing an aryl or hetaryl group in position 6, was prepared and screened for biological activity. The fluororibo derivatives were prepared by aqueous palladium catalyzed cross-coupling reactions of the corresponding 6-chloro-7-deazapurine 2′-deoxy-2′-fluororibonucleoside 11 with (het)arylboronic acids. The key intermediate 11 was prepared by a six-step sequence from the corresponding arabinonucleoside by selective protection of 3′- and 5′-hydroxyls by acid-labile groups followed by stereoselective SN2 fluorination and deprotection. The difluororibo-series was prepared by non-stereoselective glycosidation of 6-chloro-7-deazapurine with benzoyl-protected 2-deoxy-2,2-difluoro-d-erythro-pentofuranosyl-1-mesylate followed by cross-couplings, separation of anomers and deprotection. The title nucleosides did not show considerable cytostatic or antiviral activity. 相似文献
14.
Tsutomu Tsuchiya Yoshiaki Takahashi Makoto Endo Sumio Umezawa Hamao Umezawa 《Journal of carbohydrate chemistry》2013,32(4):587-611
2′,3′-Dideoxy-2′-fluorokanamycin A (23) was prepared by condensation of 6-azido-4-0-benzoyl-2,3,6-trideoxy-2-fluoro-α-D-ribo-hexopyranosyl bromide (13) and a protected disaccharide (19). Methyl 4,6-0-benzylidene-3-deoxy-β-D-arabino-hexopyranoside (5) prepared from methyl 4,6-0-benzylidene-3-chloro-3-deoxy-β-D-allo-hexopyranoside (1) by oxidation with pyridinium chlorochromate followed by reduction with Na2 S2O4 was fluorinated with the DAST reagent to give methyl 4,6-O-benzylidene-2,3-dideoxy-2-fluoro-β-D-ribo-hexopyranoside (7). Successive treatment of 7 with NBS, NaN3 and SOBr2 gave 13. The structure of the final product (23) was determined by the 1H and 19F and shift-correlated 2D NMR spectra. 相似文献
15.
Nikiforova E. A. Makhmudov R. R. Rudin A. A. Dmitriev M. V. Baibarodskikh D. V. Kirillov N. F. Zverev D. P. Romanov A M. 《Russian Journal of General Chemistry》2021,91(1):64-71
Russian Journal of General Chemistry - Depending on the ring size in the Reformatsky reagent and the nature of substituents in arylmethylidene fragment, the reactions of Reformatsky reagents... 相似文献
16.
《Tetrahedron: Asymmetry》1998,9(12):2035-2042
A new synthetic procedure for the formation of 2-amino-2′-hydroxy-1,1′-binaphthyl, and a new purification procedure through the formation of Schiff bases, purification of the Schiff bases, and breakdown of the Schiff bases through amine exchange, are described. Through the new purification procedure, greater than 99% purity of the compound can be obtained easily and reliably. A set of procedures were examined to compare the efficiency and reliability to resolve 2-amino-2′-hydroxy-1,1′-binaphthyl into enantiomers. A new procedure was discovered to enrich enantiomeric excess from less than 10% to 95–99% in one step. Even a racemic mixture from an achiral procedure can be enriched to 67% e.e. in about 4% yield. The X-ray crystal structure of the racemic mixture [rhombohedral, space group Iba2, a=15.718(2) Å, b=21.703(2) Å, c=8.5398(9) Å, V=2913.2(5) Å3, R1=0.0705, Z=8, dcalcd=1.301 g/cm3, F(000)=1200 e] was solved to elucidate the intriguing behavior of this compound. 相似文献
17.
In the reaction of 2-pyridyllithium with quinoline 1-oxide and isoquinoline 2-oxide a nucleophilic substitution of hydrogen
occurs to form the corresponding pyridin-2-ylquinolines. A dimerization of the substrate occurs with pyridine 1-oxide, 2,2′-bipyridine
1-oxide or quinoxaline N-oxide. A similar dimerization in good yield occurs when treating azine N-oxides with tert-butyllithium and this serves as a simple and convenient method for preparing bi- and tetrapyridines.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 223–229, February, 2009. 相似文献
18.
Abstract Continuing our studies on new reaction of trimethylsilylphosphites 1 we now report the conversion of compounds 1 to the corresponding phosphorazolides or phosphoranilidates by the reaction of readily available trimethylsilylphosphites 1 and 1,l'-oxalyldiazolides or anilidates. 相似文献
19.
20.
《催化学报》2003,(5)
N pentamethylene N′ arylureasareimportantfinechemicalintermediatesinindustriesofdye ,pig ment,pharmaceuticaland pesticide.At present,theirindustrialsynthesisusesphosgenewhichisofhightoxicity[1 ,2 ] .Averypromisingnon phosgena tionprocessforsynthesisofvariousunsymmetricureasisthereductivecarbonylationofnitro com poundsortheoxidativecarbonylationofanilinescat alyzedbynoblemetals,includingrhodium ,rutheni umandpalladium ,butthecatalystsarenoteasilyrecovered[3 ,4] .Sonodaetal[5 ,6] havereportedth… 相似文献