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双芳亚甲基环酮与睛氧化物进行l,3-偶极环加成反应,合成了15个新的双螺异噁唑啉类化合物. 采用元素分析、NMR、IR以及X射线单晶衍射等多种谱学技术对产物进行详细表征, 而产物的晶体结构表明了此类反应具有高度的区域选择性, 而密度泛函计算结果合理地解释了实验结果. 相似文献
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Stefanie Knak Wolf‐Diethard Pfeiffer Horst Dollinger Ashot S. Saghyan Peter Langer 《Journal of heterocyclic chemistry》2015,52(2):463-467
Imidazo[2,1‐b][2H‐1,3,4]thiadiazines were prepared by cyclization of 2‐amino‐5‐(4‐chlorophenyl)‐6H‐1,3,4‐thiadiazine with α‐haloketones. 1,2,4‐Triazolo[3,4‐b][2H‐1,3,4]thiadiazines were prepared by cyclization of 4‐amino‐5‐sulfanyl‐l,2,4‐triazoles with phenacyl bromides. 相似文献
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Synthesis of Heterocyclic Analogs of α‐aminoadipic Acid and its Esters Based on Imidazo[2,1‐b][1,3]Thiazole
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Algirdas Šačkus Diana Bričkutė Osvaldas Paliulis Frank Abildgaard Sløk 《Journal of heterocyclic chemistry》2015,52(4):1032-1036
A method for the preparation of heterocyclic analogs of α‐aminoadipic acid and its esters based on the imidazo[2,1‐b][1,3]thiazole ring system was developed. In this method, free‐radical bromination of ethyl 6‐methylimidazo[2,1‐b][1,3]thiazole‐5‐carboxylate with NBS afforded a versatile building block, ethyl 6‐bromomethylimidazo[2,1‐b][1,3]thiazole‐5‐carboxylate. Coupling of ethyl 6‐bromomethylimidazo[2,1‐b][1,3]thiazole‐5‐carboxylate with Schöllkopf's chiral auxiliary followed by acidic hydrolysis generated ethyl 6‐[(2S)‐2‐amino‐3‐methoxy‐3‐oxopropyl]imidazo[2,1‐b][1,3]thiazole‐5‐carboxylate. A similar procedure using diethyl (Boc‐amino)malonate yielded racemic 2‐amino‐3‐[(5‐ethoxycarbonyl)imidazo[2,1‐b][1,3]thiazol‐6‐yl]propanoic acid. 相似文献
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Yulin Ling Haochong Liu Aiting Zheng Guobin Li Xiaofang Li 《Journal of heterocyclic chemistry》2013,50(5):1009-1013
The reaction involving 4‐phenyl‐octahydro‐pyrano[2,3‐d]pyrimidine‐2‐thione, ethyl chloroacetate and the appropriate aromatic aldehyde yielded 2‐arylmethylidene‐5‐phenyl‐5a,7,8,9a‐tetrahydro‐5H,6H‐pyrano[2,3‐d][1,3]thiazolo[3,2‐a]pyrimidin‐3(2H)‐ones. The 1,3‐dipolar cycloaddition of 2‐arylmethylidene‐5‐phenyl‐5a,7,8,9a‐tetrahydro‐5H,6H‐pyrano[2,3‐d][1,3]thiazolo[3,2‐a]pyrimidin‐3(2H)‐ones with azomethine ylide generated by a decarboxylative route from sarcosine and acenaphthenequinone afforded 4′‐aryl‐1′‐methyl‐5″‐phenyl‐5a″,7″,8″,9a″‐tetrahydro‐2H,5″H,6″H‐dispiro[acenaphthylene‐1,2′‐pyrrolidine‐3′,2″‐pyrano[2,3‐d][1,3]thiazolo[3,2‐a]pyrimidine]‐2,3″‐diones in moderate yields. The structures of the products were determined and characterized thoroughly by NMR, MS, IR, elemental analysis, and X‐ray crystallographic analysis. 相似文献
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《Journal of heterocyclic chemistry》2017,54(4):2405-2416
3(5)‐Aminopyrazole derivative ( 6 ) has been synthesized by the reactions of the versatile unreported 2‐cyano‐N ′‐(1‐(3‐methyl‐6‐phenylimidazo[2,1‐b ]thiazol‐2‐yl)ethylidene)acetohydrazide ( 3 ) with phenyl isothiocyanate in KOH/DMF solution followed by reaction with methyl iodide and hydrazine hydrate. Reaction of compound 6 with some 1,3‐dicarbonyl compounds yielded pyrazolo[1,5‐a ]pyrimidine derivatives ( 14 – 17 ). Alkylation of compound 6 with various halo reagents, followed by intramolecular cyclization, yielded the corresponding imidazo[1,2‐b ]pyrazole derivatives 27 , 29 , 31 , and 33 . All newly synthesized compounds were elucidated by considering the data of both elemental analysis and spectral data. 相似文献
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Synthesis and Structural Characterization of Pyrrole Heterocyclic Systems Bearing Amino Acid Units: Novel Pyrrol‐3‐ones,Pyrrolo[1,2‐a][3,1]benzoxazines,and Pyrrolo[2,1‐b][1,3]oxazoles
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İrfan Koca Mustafa Saçmacı Filiz Yılmaz Şevket Hakan Üngören 《Journal of heterocyclic chemistry》2014,51(1):212-218
Furan‐3‐one derivatives 1 were converted into 2‐hydroxy‐pyrrole‐3‐ones 4 by reacting with various α‐ and β‐amino acids. In contrast, the reaction of furan‐3‐ones and 1‐aminocyclobutanecarboxylic acid afforded spiro‐pyrrolo[2,1‐b][1,3]oxazoles 5 via the pyrrole‐3‐one intermediate under the same reaction conditions. Some of 2‐hydroxy‐pyrrole‐3‐ones 3 derived from anthranilic acids were transformed to pyrrolo[1,2‐a][3,1]benzoxazines via intramolecular esterification. 相似文献
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《Journal of heterocyclic chemistry》2018,55(6):1391-1397
A 2‐(2‐Mercapto‐4‐(4‐phenoxyphenyl)‐6‐(thiophen‐2‐yl)‐1,6‐dihydropyrimidin‐5‐yl) acetic acid was used as a reactive key precursor to design various pyrimidine derivatives such as thiazolo[3,2‐a]pyrimidines and pyrimido[2,1‐b][1,3]thiazines. The chemical structures of the newly synthesized products were confirmed by their elemental analyses and spectral data (IR, 1H NMR, 13C NMR, and mass spectra). The antibacterial and antifungal activities of some of the synthesized products were also evaluated, and it was found that compounds 3, 5, 9 , and 11 exhibited potent activity against tested microorganisms in comparison with standard drugs. 相似文献
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Li Xiaofang Liu Bin Liu Haochong Yu Xianyong Yi Pinggui 《Journal of heterocyclic chemistry》2012,49(5):1050-1053
The 1,3‐dipolar cycloaddition of azomethine ylide generated in situ from isatin and sarcosine to 5‐arylmethylidene thiazolo[3,2‐b][1,2,4]triazol‐6(5H)‐ones afforded novel 1′‐methyl‐4′‐aryldispiro[indole‐3,2′‐pyrrolidine‐3′,5″‐[1,3]thiazolo[3,2‐b][1,2,4]triazole]‐2,6″ (1H)‐diones in moderate yields. The structures of all the products were characterized thoroughly by NMR, infrared spectroscopy (IR), mass spectroscopy (MS) elemental analysis together with X‐ray crystallographic analysis. 相似文献
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Vaida Miliinait Elena Plytninkien Roberta Bakien Aurimas Bieliauskas Sonata Kriktolaityt Greta Ra
kauskien Egl Arba
iauskien Algirdas a
kus 《Molecules (Basel, Switzerland)》2021,26(18)
A simple and efficient synthetic route to the novel 3a,4-dihydro-3H,7H- and 4H,7H-pyrazolo[4′,3′:5,6]pyrano[4,3-c][1,2]oxazole ring systems from 3-(prop-2-en-1-yloxy)- or 3-(prop-2-yn-1-yloxy)-1H-pyrazole-4-carbaldehyde oximes has been developed by employing the intramolecular nitrile oxide cycloaddition (INOC) reaction as the key step. The configuration of intermediate aldoximes was unambiguously determined using NOESY experimental data and comparison of the magnitudes of 1JCH coupling constants of the iminyl moiety, which were greater by approximately 13 Hz for the predominant syn isomer. The structures of the obtained heterocyclic products were confirmed by detailed 1H, 13C and 15N NMR spectroscopic experiments and HRMS measurements. 相似文献
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The three‐component reaction of N‐phenacylbenzothiazolium bromides, aromatic aldehydes and indane‐1,3‐dione in ethanol at room temperature in the presence of triethylamine as base afforded functionalized spiro[benzo[d]pyrrolo[2,1‐b]thiazole‐3,2′‐indenes] in good yields and with high diastereoselectivity. The 1H NMR data and single crystal structure clearly indicated that the obtained spiro compounds predominately have one diastereoisomer. 相似文献
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Shogo Ihara Takashi Soma Daigo Yano Shunichi Aikawa Yasuhiko Yoshida 《Journal of heterocyclic chemistry》2011,48(3):577-581
The cycloaddition reaction of cyclic imidates, 2‐benzyl‐5,6‐dihydro‐4H‐1,3‐oxazines 1a , 1b , 1c , 1d , 1e , 1f , with dimethyl acetylenedicarboxylate 2 , trimethyl ethylenetricarboxylate 4 , or dimethyl 2‐(methoxymethylene)malonate 6 afforded new fused heterocyclic compounds, such as methyl (6‐oxo‐3,4‐dihydro‐2H‐pyrrolo[2,1‐b]‐1,3‐oxazin‐7‐ylidene)acetates 3a , 3b , 3c , 3d , 3e , 3f (71–79%), dimethyl 2‐(6‐oxo‐3,4,6,7‐tetrahydro‐2H‐pyrrolo[2,1‐b]‐1,3‐oxazin‐7‐yl)malonates 5b , 5c , 5d , 5e , 5f (43–71%), or methyl 6‐oxo‐3,4‐dihydro‐2H,6H‐pyrido[2,1‐b]‐1,3‐oxazine‐7‐carboxylates 7a , 7b , 7c , 7d , 7e , 7f (32–59%), respectively. In these reactions, 1a , 1b , 1c , 1d , 1e , 1f (cyclic imidates, iminoethers) functioned as their N,C‐tautomers (enaminoethers) 2 to α,β‐unsaturated esters 2 , 4, and 6 to give annulation products 3 , 5 , and 7 following to the elimination of methanol, respectively. J. Heterocyclic Chem., (2011). 相似文献
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Expedient Synthesis of Novel Ferrocenyl Spiropyrrolidines Through 1,3‐Dipolar Cycloaddition Reaction
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The synthesis of novel ferrocenyl spiropyrrolidines through the cycloaddition of azomethine ylides generated by a decarboxylative route from sarcosine and diketones with the dipolarophile, Knoevenagel adduct of ferrocene carbaldehyde is described. The regiochemistry and stereochemistry of the cycloadducts were confirmed by X‐ray analysis of one of the synthesized cycloadducts. 相似文献
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Kai‐Kai Wang Yan‐Li Li Guo‐Yang Ma Meng‐Hao Yi Bao‐Ku Zhu 《Journal of heterocyclic chemistry》2019,56(8):2274-2280
A rapid and highly efficient 1,3‐dipolar [3 + 2] cycloaddition of nonstabilized azomethine ylides generated in situ with benzo[b]thiophene 1,1‐dioxides as the dipolarophiles has been developed. The efficient method affords tricyclic pyrrolidine‐fused benzo[b]thiophene 1,1‐dioxide derivatives in high to excellent yields (up to 99%) with excellent diastereoselectivities (up to >25:1 dr) under mild reaction conditions. The structure of a typical product was confirmed by X‐ray crystallography. 相似文献
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Synthesis of Spirocyclic and Tricyclic Isoxazoline via 1,3‐Dipolar Cycloaddition Reactions
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1,3‐Dipolar cycloadditions of the bicyclic monoterpenes (S)‐(?)‐camphene ( 1 ), (R)‐(+)‐a‐pinene ( 2 ), and (S)‐(?)‐b‐pinene ( 3 ) with aryl and heteroaryl nitrile oxides afforded new spirocyclic and tricyclic isoxazoline derivatives 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 whose biological activities were evaluated in bioassay studies. 相似文献
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Eligeti Rajanarendar Paka Venkateshwarlu Saini Ramakrishna Dharavath Nagaraju 《Journal of heterocyclic chemistry》2015,52(4):1007-1013
Synthesis of novel 2‐3‐methyl‐5‐[(E)‐2‐aryl‐1‐ethenyl]‐4‐isoxazolyl‐4,10a‐diaryl‐1,10a‐dihydro‐2H‐benzo[d]pyrazino[2,1‐b][1,3]oxazoles 5 were simply achieved by the reaction of 2‐[3‐methyl‐5‐[(E)‐2‐aryl‐1‐ethenyl]‐4‐isoxazolyl(2‐oxo‐2‐arylethyl)amino]‐1‐aryl‐1‐ethanones 3 with o‐aminophenol 4 in the presence of CAN catalyst. The intermediates, 2‐[3‐methyl‐5‐[(E)‐2‐aryl‐1‐ethenyl]‐4‐isoxazolyl(2‐oxo‐2‐arylethyl)amino]‐1‐aryl‐1‐ethanones 3 , were prepared by the reaction of 4‐amino‐3‐methyl‐5‐styrylisoxazole 1 , with phenacylbromides 2 in ethanol in the presence of K2CO3. The structures of the newly synthesized compounds 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l and 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k , 5l have been confirmed by analytical and spectral data. 相似文献
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Demetrios N. Nicolaides Daman R. Gautam Konstantinos E. Litinas Dimitra J. Hadjipavlou‐Litina Christos A. Kontogiorgis 《Journal of heterocyclic chemistry》2004,41(4):605-611
The O‐methylmonoximes 2,3 of stenocarpoquinone‐A and β‐lapachone reacted with methyl phenylacetate to give 1,4‐benzoxazine derivatives 8a, 8b and oxazole 11a. Compound 8a was transformed to compounds 13I , 13II , 14. Treatment of compound 14 with osmium tetroxide afforded compounds 15 , 16 and esterification of the latter gave the bis‐ and mono‐ esters 17I , 17II , 18. All products are strongly fluorescent. Compounds 8a,b , 11a , 13–18 (azabenzo analogues of khellactones) were tested for their ability to interact with DPPH, to compete with dimethylsulfoxide for hydroxyl radicals, to inhibit soybean lipoxygenase and trypsin activities in vitro. Compounds 16 and 17II were found to compete significantly with dimethylsulfoxide for hydroxyl radicals, whereas compounds 8a , 11a , 14 and 17I were found to inhibit strongly soybean lipoxygenase. 相似文献