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1.
1,5‐Benzodiazepin‐2‐yl‐phosphonates were facilely synthesized via a one‐pot three‐component condensation of o‐diaminobenzene, 1,3‐diketone and diethyl phosphite in the presence of a catalytic amount of ytterbium chloride under mild reaction conditions. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:89–95, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20573 相似文献
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Yasuhiro Kamitori 《Journal of heterocyclic chemistry》2001,38(3):773-776
1,1,1‐Trifluoro‐2,3‐alkanediones 2 easily obtainable from various aldehyde dialkylhydrazones were reacted with several diamines to afford trifluoromethylquinoxalines 3 and trifluoromethylpyrazines 4 in good yields. With the use of aldehydes and aqueous ammonia instead of diamines, diketones 2 were successfully converted to the corresponding 4‐trifluoromethylimidazoles 5 in satisfactory yields. 相似文献
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Dialkyl and dithioalkyl N‐protected 1‐aminoalkylphosphonates were synthesized using reactions of benzyl carbamate, aldehydes and chlorophosphites, or dithioalkyl chlorophosphite, respectively. This represents a novel synthetic method for 1‐aminoalkylphosphonates. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:417–421, 2000 相似文献
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A facile synthesis of 2‐amino‐1,3‐selenazole by reaction of N,N‐unsubstituted selenourea with ketone
2‐Dialkylamino‐1,3‐selenazoles were yielded by the reaction of N,N‐unsubstituted selenoureas with ketones in the presence of ferric chloride. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:88–92, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20180 相似文献
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Enamul Karim Kaushal Kishore Jai N. Vishwakarma 《Journal of heterocyclic chemistry》2003,40(5):901-903
A facile one‐pot synthesis of 5‐benzoyl‐6‐methylthio‐1,2,3,4‐tetrahydropyrimidines in good yields is reported. 相似文献
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Wenqing Lin Frank Seela Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(8):o566-o568
In the tricyclic nucleoside 7‐(β‐d ‐ribofuranosyl)‐7H‐imidazo[1,2‐c]pyrazolo[4,3‐e][1,2,3]triazine, C11H12N6O4, the conformation of the N‐glycosyl bond is intermediate between anti and high anti [χ = −103.5 (3)°]. The ribofuranose moiety adopts a 3T2 sugar pucker (S‐type sugar) and the conformation at the exocyclic C—C bond is ap (gauche–trans). Molecules of the title compound form a three‐dimensional network via three medium–strong intermolecular hydrogen bonds (one O—H⋯N and two O—H⋯O bonds). 相似文献
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Heong‐Seup Yim Ho‐Kyun Kim Jeum‐Jong Kim Deok‐Heon Kweon Yong‐Jin Yoon Sang‐Gyeong Lee Jung‐Ho Kim 《Journal of heterocyclic chemistry》2007,44(4):909-914
1‐Alkyl‐5‐arylalkoxy‐6‐methoxy‐3,4‐dihydroisoquinolines were synthesized by the alkylation of 1‐alkyl‐5‐hydroxy‐6‐methoxy‐3,4‐dihydroisoquinolines with arylalkyl halide in the presence of potassium carbonate. 1‐Alkyl‐5‐hydroxy‐6‐methoxy‐3,4‐dihydroisoquinolines as key precursor prepared from o‐vaniline via 6 steps. 相似文献
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Treatment of triphenylphosphine with dialkyl acetylenedicarboxylate leads to 1:1 adduct and concomitant protonation of late adduct by pentan‐2,3,4‐trione 3‐oxime gave the reactive intermediate, vinyltriphenylphosphonium salts, which undergoes an intramolecular Wittig reaction to produce tetrasubstituted N‐hydroxypyrroles in fairly high yields. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:100–103, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20382 相似文献
10.
Sixteen 5‐alkylamino‐3,6‐diaryl‐2‐thioxo‐2,3,6,7‐tetrahydrothiazolo[4,5‐d]pyrimidin‐7‐ones 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k , 4l , 4m , 4n , 4o , 4p were designed and easily synthesized via a tandem aza‐Wittig reaction. The iminophosphorane 2 , obtained from reaction of 1 with triphenylphosphine, hexachloroethane and Et3N, reacted with aromatic isocyanate to give carbodiimide 3 . carbodiimide 3 reacted with alkylamines to provide the title compounds in 45–61% isolated yields in presence of catalytic amount of ethoxide. The structures of compounds 4 were confirmed by 1H NMR, IR, MS, and elemental analysis. J. Heterocyclic Chem., 2011. 相似文献
11.
Aamer Saeed 《Journal of heterocyclic chemistry》2004,41(6):975-978
A facile and straightforward synthesis of cytogenin 1 (8‐hydroxy‐3‐hydroxymethyl‐6‐methoxyisocoumarin) metabolite of Streptoverticillium eurocidicum and Certocystis fimbriata has been achieved. Condensation of chloroacetyl chloride with 3,5‐dimethoxyhomophthalic acid 2 directly furnished 3‐chloromethyl‐6,8‐dimethoxyisocoumarin 3 which was hydrolyzed to 6,8‐dimethoxy‐3‐hydroxymethylisocoumarin 4 using 0.05% aqueous sodium hydroxide in THF. Regioselective demethylation of 4 yielded cytogenin 1 . In model experiments, 3‐chloromethylisocoumarin was prepared and converted into 3‐hydroxymethyl isocoumarin. 相似文献
12.
Adam D. Celiz Oren A. Scherman 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5833-5841
Three new ureidopyrimidinone(UPy)‐functionalized chain‐transfer agents (CTAs) have been synthesized for use in reversible addition‐fragmentation chain transfer (RAFT) polymerization. These UPy‐CTAs are able to polymerize a wide variety of vinyl monomers to yield UPy‐functionalized polymers, including homopolymers, block copolymers, and amphiphilic block copolymers. These polymers have been characterized via 1H and 13C NMR spectroscopy, gel permeation chromatography (GPC), UV/visible spectroscopy and differential scanning calorimetry (DSC) to demonstrate end‐group fidelity. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
13.
A multistep synthesis of a mannose 6‐phosphonate‐based glycolipid is described involving (1) a one‐carbon chain elongation at the 6‐position of mannose, followed by (2) phosphonation, using tris(trimethylsilyl)phosphite. This method was shown to e efficient and provides a general route to various mannose 6‐phosphonate‐based compounds for the design of drug delivery systems. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:241–246, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10134 相似文献
14.
K. R. Ravi Kumar Basappa K. S. Rangappa H. Mallesha 《Journal of heterocyclic chemistry》2003,40(4):607-609
A selective reduction and its subsequent cyclisation of novel isoxazolidines into γ‐lactams have been examined in presence of Raney ‐ nickel catalyst. 相似文献
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R. T. Pardasani P. Pardasani V. Chaturvedi S. K. Yadav A. Saxena I. Sharma 《Heteroatom Chemistry》2003,14(1):36-41
A cyclic secondary α‐amino acid, viz. L ‐proline, reacts with isatin derivatives via decarboxylative azomethine ylide formation and subsequent cycloaddition with various dipolarophiles to give cycloadducts in moderate to good yield. Theoretical studies have been performed to study the stereochemistry of the products formed. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:36–41, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10063 相似文献
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The valuable new synthetic intermediates, ethyl 4‐, 6‐ and 7‐formyl‐1H‐indole‐2‐carboxylates ( 10, 11, 12 ) were prepared from 2‐ethoxycarbonyl‐1H‐indole‐4‐, 6‐ and 7‐methanesulfonic acids ( 1, 2, 3 ), respectively. The transformation of sulfomethyl group to formyl function was accomplished through elimination of SO2 to yield ethyl 4‐, 6‐ and 7‐chloromethyl‐1H‐indole‐2‐carboxylates ( 4, 5, 6 ), hydrolysed to ethyl 4‐, 6‐ and 7‐hydroxymethyl‐1H‐indole‐2‐carboxylates ( 7, 8, 9 ), then oxidized to aldehydes ( 10, 11, 12 ). Protection at N1 of indole was not necessary. A marked increase in the rate of hydrolysis of 7‐chloromethyl‐indoles compared to that of 4‐ and 6‐(chloromethyl)indoles was observed. 相似文献
18.
Pengfei Yang Guangming Zhu Shuogui Xu Xiaoyan Zhang Xuelin Shen Xiaoping Cui Yuliang Gao Jing Nie 《Journal of Polymer Science.Polymer Physics》2017,55(8):692-701
A facile method to prepare shape memory polymers crosslinked by SiO2 is described. A series of biodegradable shape memory networks were obtained through thiol‐ene reaction triggered by UV irradiation between surface‐thiol‐modified SiO2 nanoparticles and end‐acrylate poly (ε‐caprolactone) (PCL). The highly selective thiol‐ene reaction ensured a uniform distribution of PCL chains between crosslinkers, contributing well‐defined network architecture with enhanced mechanical and shape‐memory properties. Thiol‐functionalized silica nanoparticle was characterized by using FTIR and XPS analysis, and 1H NMR spectra was used to confirm the successful modification of terminal hydroxyl group of PCL diol. Surface‐modified silica particles were found well dispersible in acrylate‐capped PCL supported by SEM. Thermal and crystalline behaviors of the obtained polymers were analyzed by DSC and XRD, and DMA measurement proved good mechanical property. The shape memory behavior and tensile strength was somewhat tunable by the length of PCL. Acceptably, sample SiO2‐SMP2k presented 99% recovery ratio and 97% shape fixity, and its relatively high tensile strength showed an attractive potential for biomedical application. Finally, a possible molecular mechanism accounting for the shape memory property was illustrated. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 692–701 相似文献
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Five new 6‐polyhaloacylnorkhellins were synthesized in high yields from diethoxymethyl acetate and the condensation products of khellinone with RFCO2Et and CCl3COCl. Reaction of 6‐polyfluoroacylnorkhellins with primary aromatic amines yielded 6‐(arylaminomethylene)‐7‐hydroxy‐4,9‐dimethoxy‐7‐(polyfluoroalkyl)furo[3,2‐g]chroman‐5‐ones. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:99–103, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20174 相似文献