- Quinazoline derivatives preparation method and use thereof
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The invention discloses a quinazoline derivative shown in formula (I) which is described in the specification and a salt thereof. In the formula, Z represents -NH- and -O-, R1 and R2 represent C1-3 alkoxy groups or hydrogen, R3 is selected from the group consisting of 4-fluoro-, 4-chloro-, 2-chloro-, 4-bromo-, 2, 4-dichloro-, 4-methyl, 4-methoxy, hydrogen, 4-trifluoromethyl and 2,4-dimethoxy. The invention relates to a preparation method and application of the compound shown in the formula (I) and the salt thereof. The compound or the salt thereof has strong inhibitory activity on colorectal cancer cell strains HCT-116, human lung cancer cell strains A549 and breast cancer cell strains MCF-7. The compound has wide spectrum antitumor activity and can be used as a drug or lead compound for treatment of diseases like tumors and cancers.
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Paragraph 0075; 0080-0082
(2019/04/02)
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- Synthesis and SAR of new isoxazole-triazole bis-heterocyclic compounds as analogues of natural lignans with antiparasitic activity
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Despite the impressive scientific and technological advances of recent decades, no effective treatment is currently available for Chagas disease. Our research group has been studying the design and synthesis of analogues of natural lignans aiming to identify compounds with antiparasitic activity. This article reports the synthesis of 42 novel bis-heterocyclic derivatives and the structure-activity relationship study conducted based on results of biological assays against Trypanosoma cruzi amastigotes. Thirty-seven compounds were active, and eight of them had GI50 values lower than 100 μM (GI50 88.4–12.2 μM). A qualitative structure activity relationship study using three dimensional descriptors was carried out and showed a correlation between growth inhibitory potency and the presence of bulky hydrophobic groups located at rings A and D of the compounds. Compound 3-(3,4-dimethoxyphenyl)-5-((4-(4-pentylphenyl)-1H-1,2,3-triazol-1-yl)methyl)isoxazole (31) was the most active in the series (GI50 12.2 μM), showing, in vitro, low toxicity and potency similar to benznidazole (GI50 10.2 μM). These results suggest that this compound can be a promising scaffold for the design of new trypanocidal compounds.
- Zimmermann, Lara A.,de Moraes, Milene H.,da Rosa, Rafael,de Melo, Eduardo B.,Paula, Fávero R.,Schenkel, Eloir P.,Steindel, Mario,Bernardes, Lílian S.C.
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p. 4850 - 4862
(2018/09/11)
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- Ferrocene derivatives, preparation method and use thereof
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The invention discloses ferrocene derivatives as shown in a formula I in the specification and salts thereof, wherein Z is O or NH; R is selected from hydrogen, fluorine, chlorine, bromine, methyl, methoxyl and trifluoromethyl; n is an integer ranging fro
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Paragraph 0076; 0077; 0081-0083
(2018/10/11)
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- Discovery of Farnesoid X Receptor Antagonists Based on a Library of Oleanolic Acid 3-O-Esters through Diverse Substituent Design and Molecular Docking Methods
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The pentacyclic triterpene oleanolic acid (OA, 1) with known farnesoid X receptor (FXR) modulatory activity was modified at its C-3 position to find new FXR-interacting agents. A diverse substitution library of OA derivatives was constructed in silico through a 2D fingerprint similarity cluster strategy. With further docking analysis, four top-scored OA 3-O-ester derivatives were selected for synthesis. The bioassay results indicated that all four compounds 3 inhibited chenodeoxycholic acid (CDCA)-induced FXR transactivation in a concentration-dependent mode. Among them 3b and 3d are more active than the parent compound OA. A molecular simulation study was performed to attempt to explain the structure-Activity relationship (SAR) and the antagonistic action. To the best of our knowledge, this is the first report on semi-synthetic pentacyclic triterpenoids with FXR-modulatory activities.
- Wang, Shao-Rong,Xu, Tingting,Deng, Kai,Wong, Chi-Wai,Liu, Jinsong,Fang, Wei-Shuo
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- Design and synthesis of a new series of 3,5-disubstituted isoxazoles active against Trypanosoma cruzi and Leishmania amazonensis
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Chagas disease and leishmaniasis are neglected tropical diseases (NTDs) endemic in developing countries. Although there are drugs available for their treatment, efforts on finding new efficacious therapies are continuous. The natural lignans grandisin (1)
- da Rosa, Rafael,de Moraes, Milene H?ehr,Zimmermann, Lara Almida,Schenkel, Eloir Paulo,Steindel, Mario,Bernardes, Lílian Sibelle Campos
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- Synthesis and in vitro biological evaluation of novel coumarin derivatives containing isoxazole moieties on melanin synthesis in B16 cells and inhibition on bacteria
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A novel series of coumarin derivatives 6a–o, bearing isoxazole moieties were designed and synthesized. After that, they were evaluated for melanin synthesis in murine B16 cells and inhibitory effect on the growth of CA (Candida albicans), EC (Escherichia coli), SA (Staphylococcus aureus). It was found that eleven compounds (6b–f, 6j–o) showed a better activity on melanin synthesis than positive control (8-MOP). Among them, compounds 6d (242%) and 6f (390%), with nearly 1.6 and 2.6-fold potency compared with 8-MOP (149%) respectively, were recognized as the most promising candidate hits for further pharmacological study of anti-vitiligo. Seven halogen substituted compounds exhibited moderate antimicrobial activity against CA. It is interesting that 6e–f and 6l–m, which had two halogens on the benzene showed a comparable activity with Amphotericin B against CA. The evaluation of melanin synthesis in B16 cells and inhibitory effect on bacteria of above structurally diverse derivatives had also led to an outline of structure-activity relationship.
- Pang, Guang Xian,Niu, Chao,Mamat, Nuramina,Aisa, Haji Akber
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supporting information
p. 2674 - 2677
(2017/05/29)
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- Ultrasonic-assisted synthesis of 1,4-disubstituted 1,2,3-triazoles via various terminal acetylenes and azide and their quorum sensing inhibition
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An efficient synthesis of 1,4-disubstituted 1,2,3-triazole derivatives was studied. 1,4-Disubstituted 1,2,3-triazoles containing isoxazole and thymidine structures were synthesized in 84–96% yields starting from various terminal isoxazole ether alkynes and β-thymidine azide derivatives via a 1,3-dispolar cycloaddition using copper acetate, sodium ascorbate as the catalyst under ultrasonic assisted condition. All the target compounds were characterized by HRMS, FT-IR, 1H NMR and 13C NMR spectroscopy. Furthermore, the quorum sensing inhibitory activities of synthesized compounds were evaluated with Chromobacterium violaceum (C. Violaceum CV026) based on their inhibition of violacein production, with compound C10-HSL as a positive control. The compounds 8a, 8c and 8f exhibited considerable levels of inhibitory activity against violacein production, and IC50 values were 217?±?19, 223?±?20 and 42.8?±?4.5?μM, respectively, which highlighted the potential of these compounds as lead structures for further research towards the development of novel QS inhibitors.
- Zhang, Da-wei,Zhang, Yu-min,Li, Jing,Zhao, Tian-qi,Gu, Qiang,Lin, Feng
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p. 343 - 353
(2016/12/23)
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- Cu(I) catalyzed microwave assisted telescopic synthesis of 3,5-disubstituted isoxazoles in green media
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A facile and efficient microwave assisted telescopic synthesis of diverse isoxazoles was reported in green reaction medium. Initially, N-hydroxyl imidoyl chlorides were reacted with substituted alkynes in aqueous medium using 2 mol% of [Cu(phen)(PPh3
- Meena,Maiti, Barnali,Chanda, Kaushik
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p. 5514 - 5517
(2016/11/19)
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- Thiophene [2, 3 - d] pyrimidine derivatives, their preparation and use thereof
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The invention provides a thiophene [2, 3-d] pyrimidine derivative containing isoxazole heterocycle shown by formula (I) or a pharmaceutically accepted salt thereof, wherein R1 and R2 are respectively selected from hydrogen, C1-6 alkyl, C1-6 alkoxy, haloge
- -
-
Paragraph 0118; 0119; 0120
(2017/02/17)
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- A rapid and efficient solvent-free microwave-assisted synthesis of pyrazolone derivatives containing substituted isoxazole ring
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An efficient synthesis of 4-substituted pyrazolone derivatives was developed. 4-Substituted pyrazolone derivatives were synthesized in 78-97% yields starting from various 3-substituted isoxazole-5-carbaldehydes, ethyl acetoacetate and hydrazine under micr
- Zhang, Dawei,Zhang, Yumin,Zhao, Tianqi,Li, Jing,Hou, Yaya,Gu, Qiang
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p. 2979 - 2987
(2016/05/19)
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- Quinazoline derivatives and their use
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The present invention provides a quinazoline compound shown in formula (I), or pharmaceutically acceptable salt thereof. R1, R2 and R7 are independently and respectively selected from hydrogen, C1-6 alkyl, C1-6 alkoxy, halogenate C1-6 alkyl, halogenate C1
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-
Paragraph 0254; 0255
(2016/10/08)
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- Synthesis and bioactivity of novel isoxazole chalcone derivatives on tyrosinase and melanin synthesis in murine B16 cells for the treatment of vitiligo
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A new series of chalcone derivatives 1–18, bearing isoxazole moieties were designed and synthesized, and biologically evaluated for their activity on mushroom tyrosinase and melanin synthesis in murine B16 cells. The result indicated that most of prepared compounds 1–18 showed potent activating effect on tyrosinase, especially for 1–2, 4, 6–7, 9 and 15. Among them, compounds 2, 4 and 9 demonstrated the best activity with EC50?=?1.3, 2.5 and 3.0?μmol·L?1respectively, much better than the positive control 8-methoxypsoralan (8-MOP, EC50?=?14.8?μmol·L?1); In B16 cells, all the tested compounds exhibited a stronger activity on melanogenesis than 8-MOP (with the value of 115%). It was interesting that derivatives substituted with halogen (1, 2, 4, 5, 7, 9) were generally more potent. Compounds 2 (463%) and 18 (438%) with 3 and 4-fold potency compared with 8-MOP respectively, were recognized as the most promising candidate hits for further pharmacological study of anti-vitiligo.
- Niu, Chao,Yin, Li,Nie, Li Fei,Dou, Jun,Zhao, Jiang Yu,Li, Gen,Aisa, Haji Akber
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p. 5440 - 5448
(2016/10/24)
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- Copper(0) Nanoparticles in Click Chemistry: Synthesis of 3,5-Disubstituted Isoxazoles
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An efficient procedure for the synthesis of 3,5-disubstituted isoxazoles via [3+2] cycloaddition reaction of in situ generated nitrile oxides with acetylenes employing readily preparable copper(0) nanoparticles is described. A variety of in situ generated
- Vishwanatha,Sureshbabu, Vommina V.
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p. 1823 - 1833
(2015/02/19)
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- Efficient solvent-free synthesis of bis(indolyl)methanes on SiO2 solid support under microwave irradiation
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An efficient synthesis of bis(indolyl)methanes was developed. Bis(indolyl)methanes were synthesized starting from various aromatic aldehydes with indole under microwave irradiation and solvent-free conditions (85-98 %). Solid support SiO2 was found to possess favorable catalytic and dispersancy parameters for the condensation reaction. Moreover, novel bis(indolyl)methanes containing an isoxazole ring were synthesized via this method in excellent yields (> 94 %) using 3-substituted isoxazole-5-carbaldehydes and indole.
- Zhang, Da-Wei,Zhang, Yu-Min,Zhang, Yi-Liang,Zhao, Tian-Qi,Liu, Hong-Wei,Gan, Yuan-Ming,Gu, Qiang
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p. 470 - 478
(2015/01/30)
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- THIOPHENE [2, 3-D]PYRIMIDINE DERIVATIVE, AND PREPARATION METHOD AND USE THEREOF
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This invention provides thieno[2,3-d]pyrimidine derivatives containing isoxazole heterocycle represented by formula (I), or pharmaceutically acceptable salts thereof Wherein: R1 and R2 may be the same or different and is independentl
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Paragraph 0065; 0066
(2015/02/25)
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- Efficient synthesis of bis-isoxazole ethers via 1,3-dipolar cycloaddition catalysed by Zn/Zn2+ and their antifungal activities
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An efficient method was developed for synthesising isoxazoles. A series of novel bis-isoxazole ether compounds VI, VII and VIII were synthesised starting from different substituted aldehydes (I) via a 1,3-dispolar cycloaddition using Zn/Zn2+ as a catalyst; these were characterised by FT-IR, HRMS, 1H NMR and 13C NMR spectroscopy. In addition, the antimicrobial properties of the synthesised products were investigated. The synthesised compounds exhibited significant antifungal activities in comparison with the standard drugs, fluconazole and itraconazole. It was found that Candida albicans was sensitive to 2-substituted phenyl bis-isoxazole ethers bearing pyridyl.
- Zhang, Da-Wei,Lin, Feng,Li, Bo-Chao,Liu, Hong-Wei,Zhao, Tian-Qi,Zhang, Yu-Min,Gu, Qiang
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p. 1500 - 1511
(2015/09/15)
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- QUINAZOLINE DERIVATIVE AND APPLICATION THEREOF
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This invention provides a class of quinazoline compounds, as represented by formula (I), and their pharmaceutically acceptable salts, wherein: each of R1 and R2 independently, is selected from H, C1-C6 alkoxy, h
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-
Paragraph 0037
(2014/07/22)
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- QUINAZOLINE DERIVATIVE AND APPLICATION THEREOF
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This invention provides a class of quinazoline compounds, as represented by formula (I), and their pharmaceutically acceptable salts, wherein: each of R1 and R2 independently, is selected from H, C1-C6 alkoxy, h
- -
-
Paragraph 0114; 0115
(2014/08/19)
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- Synthesis of novel 5-(3-alkylquinolin-2-yl)-3-aryl isoxazole derivatives and their cytotoxic activity
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The propargyl alcohol on reaction with aldoxime and NaOCl in DCM gave exclusively (3-arylisoxazol-5-yl) methanol 1. The compound 1 was oxidized to an aldehyde 2 followed by reaction with aniline resulted in Schiff's base 3. The compounds 3 were further re
- Sambasiva Rao,Kurumurthy,Veeraswamy,Poornachandra,Ganesh Kumar,Narsaiah
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p. 1349 - 1351
(2014/03/21)
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- GLYCINE TRANSPORTER INHIBITING SUBSTANCES
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The present invention aims to provide novel compounds of formula [I] or pharmaceutically acceptable salts thereof that are based on a glycine uptake inhibiting action and which are useful in the prevention or treatment of such diseases as schizophrenia, Alzheimer's disease, cognitive dysfunction, dementia, anxiety disorders (generalized anxiety disorder, panic disorder, obsessive-compulsive disorder, social anxiety disorder, posttraumatic stress disorder, specific phobia, acute stress disorder, etc.), depression, drug addiction, spasm, tremor, pain, and sleep disorder:
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Paragraph 0430; 0432; 0435; 0436
(2013/07/25)
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- One-pot synthesis of 3,5-disubstituted isoxazoles from propargylic alcohols through propargylic N-hydroxylamines
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An efficient approach has been described for the synthesis of 3,5-disubstituted isoxazoles from propargylic alcohols. The strategy involves a one-pot p-TSA-catalyzed N-propargylation of protected hydroxylamines followed by a TBAF-mediated detosylative 5-endo-dig cyclization. The method was successfully used for the synthesis of various 3,5-disubstituted isoxazoles.
- Raji Reddy, Chada,Vijaykumar, Jonnalagadda,Jithender, Enukonda,Reddy, Gangireddy Pavan Kumar,Gree, Rene
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p. 5767 - 5773
(2012/11/07)
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- One-pot synthesis of (3-phenylisoxazol-5-yl) methanol derivatives under ultrasound
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An ultrasonic-assisted, one-pot, efficient, convenient procedure for the synthesis of (3-phenylisoxazol-5-yl)methanol derivatives has been developed. (3-Phenylisoxazol-5-yl)-methanol derivatives with biological and pharmaceutical property have been synthe
- Shen, Chuansheng,Zhang, Yumin,Gan, Yuanming,Zhao, Tianqi,Gu, Qiang
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experimental part
p. 278 - 281
(2012/04/18)
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- Design, synthesis and antibacterial activity of novel N-formylhydroxylamine derivatives as PDF inhibitors
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A new series of N-formylhydroxylamines 11a-i have been synthesized through a multi-step protocol starting from diethyl malonate. These compounds have been structurally characterized by IR, 1H NMR and HRMS. All the synthesized compounds 11a-i have been screened for antibacterial activities. All the compounds are found to exhibit potent in vitro inhibitory activity against Staphylococcus aureus and relatively weak antibacterial activity against Klebsiella pneumoniae.
- Yin,Jia,Zhao,Xu,Tang,Wang
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experimental part
p. 695 - 703
(2011/07/29)
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- Silver-catalyzed synthesis of disubstituted isoxazoles by cyclization of alkynyl oxime ethers
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A facile and practical synthesis of 3,5-disubstituted isoxazoles via a silver-catalyzed cyclization and subsequent protonation of alkynyl oxime ethers has been developed. The methodology was successfully applied to the synthesis of a biologically active i
- Ueda, Masafumi,Ikeda, Yuki,Sato, Aoi,Ito, Yuta,Kakiuchi, Maiko,Shono, Hiroko,Miyoshi, Tetsuya,Naito, Takeaki,Miyata, Okiko
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p. 4612 - 4615
(2011/07/08)
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- Synthesis and preliminary antibacterial evaluation of 2-butyl succinate-based hydroxamate derivatives containing isoxazole rings
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Two series of novel 2-butyl succinate-based Hydroxamate derivatives containing isoxazole rings were synthesized, characterized and evaluated for antibacterial activity. The synthesized compounds were found to exhibit weak to moderate inhibitory activity against Staphytlococcus aureu and Klebsiellar pneumonia in vitro. All the compounds synthesized were found to be more effective against Klebsiellar pneumonia compared to Staphytlococcus aureu.
- Zhang, Datong,Jia, Jiong,Meng, Lijuan,Xu, Weiren,Tang, Lida,Wang, Jianwu
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experimental part
p. 831 - 842
(2012/01/04)
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- Concise synthesis and antimicrobial activities of new substituted 5-isoxazolpenicillins
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The synthesis of a series of new 5-isoxazolpenicillins is described, which were obtained by coupling substituted isoxazoles with 6-APA. Concise large-scale synthesis of 3,5-disubstituted isoxazoles by 1,3-dipolar cycloaddition using copper(I) as catalyst was also investigated. Representative compounds were assayed for antimicrobial activities, showing satisfactory antimicrobial activities against Gram-negative bacteria.
- Wang, Xi-Zhao,Jia, Jiong,Zhang, Yan,Xu, Wei-Ren,Liu, Wei,Shi, Fang-Niu,Wang, Jian-Wu
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p. 643 - 652
(2008/03/11)
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- METHODS FOR THE SYNTHESIS OF HETEROAROMATIC COMPOUNDS
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Methods of making heteroaromatic compounds comprising a 5- membered ring, and dihydro forms thereof, by a metal catalysed 5-endo-cyclisation of alkynes (acetylenes) are disclosed. The methods involve the use of a catalyst comprising a silver salt, more preferably a silver (I) salt, which is employed as a heterogeneous catalyst for the cyclisation reaction. The methods can produce different types of heteroaromatic compounds and are capable of producing highly substituted products, i.e. products in which the 5-membered ring is disubstituted, trisubstituted or, with further simple reactions, tetrasubstituted. The methods described herein generally the advantages that they use conditions and reagents that are benign, cheap and flexible and amenable to scale up, and in which the only by-product is water.
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Page/Page column 38
(2008/06/13)
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- Ramoplanin derivatives possessing antibacterial activity
-
Novel ramoplanin derivatives are disclosed. These ramoplanin derivatives exhibit antibacterial activity. As the compounds of the subject invention exhibit potent activities against gram positive bacteria, they are useful antimicrobial agents. Methods of synthesis and of use of the compounds are also disclosed.
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Page/Page column 39; 56
(2010/11/23)
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- Soluble polymer-supported synthesis of isoxazoles
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The first soluble polymer-supported synthesis of isoxazoles through a 1,3-dipolar cycloaddition is described. A soluble polymer-supported alkyne reacts with nitrile oxides generated in situ to give isoxazoles in good yield.
- Shang, Yong-Jia,Wang, Yan-Guang
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p. 2247 - 2249
(2007/10/03)
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- Synthesis of isoxazolines and isoxazoles using poly(ethylene glycol) as support
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A general method for the liquid-phase syntheses of isoxazoles and isoxazolines through a 1,3-dipolar cycloaddition is described. The poly(ethylene glycol) (PEG)-supported alkyne 2 or alkene 6 reacted with nitrile oxides generated in situ from aldoximes 3, followed by cleavage from the PEG, to give isoxazoles or isoxazolines in good yield and purity.
- Shang, Yong-Jia,Wang, Yan-Guang
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p. 1663 - 1668
(2007/10/03)
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- Oxyiminoalkanoic acid derivatives with hypoglycemic and hypolipidemic activity
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This invention provides a novel oxyiminoalkanoic acid derivative which has excellent hypoglycemic and hypolipidemic actions and which is used for the treatment of diabetes mellitus, hyperlipemia, insulin insensitivity, insulin resistance and impaired glucose tolerance.
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- Substituted tetrahydropyrrolo[2,1-b]oxazol-5(6H)-ones and tetrahydropyrrolo[2,1-b]thiazol-5(6H)-ones as hypoglycemic agents
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A series of substituted tetrahydropyrrolo[2,1-b]oxazol-5(6H)-ones and tetrahydropyrrolo[2,1-b]thiazol-5(6H)-ones was synthesized from amino alcohols or amino thiols and keto acids. A pharmacological model based on the results obtained with these compounds led to the synthesis and evaluation of a series of isoxazoles and other monocyclic compounds. These were evaluated for their ability to enhance glucose utilization in cultured L6 myocytes. The in vivo hypoglycemic efficacy and potency of these compounds were evaluated in a model of type 2 diabetes mellitus (non-insulin-dependent diabetes mellitus), the ob/ob mouse. 25a(2S) (SDZ PGU 693) was selected for further pharmacological studies.
- Aicher, Thomas D.,Balkan, Bork,Bell, Philip A.,Brand, Leonard J.,Cheon,Deems, Rhonda O.,Fell, Jay B.,Fillers, William S.,Fraser, James D.,Gao, Jiaping,Knorr, Douglas C.,Kahle, Gerald G.,Leone, Christina L.,Nadelson, Jeffrey,Simpson, Ronald,Smith, Howard C.
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p. 4556 - 4566
(2007/10/03)
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- A strategic alternative to solid phase synthesis: Preparation of a small isoxazoline library by 'fluorous synthesis'
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The preparation of a highly fluorinated silyl group and its use as a 'fluorous label' are described. Allyl and propargyl alcohols are rendered fluorous upon attachment to the fluorous label. Cycloaddition of the fluorous dipolarophiles to nitrile oxides provides the corresponding isoxazol(in)es which are purified by simple liquid-liquid extractions. After detachment of the label and renewed extraction, the organic isoxazol(in)es are obtained. This new fluorous methodology allows the preparation of isoxazol(in)es in high purities without using chromatography.
- Studer, Armido,Curran, Dennis P.
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p. 6681 - 6696
(2007/10/03)
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- Generation of Nitrile Oxides via O-Tributylstannyl Aldoximes; Application to the Synthesis of Isoxazolines and Isoxazoles
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Nitrile oxides were generated readily by the reaction of aldoximes 1, with tert-butyl hypochlorite and bis(tributyltin) oxide.The reaction proceeded efficiently under mild conditions, in which O-stannylated aldoximes 2 are thought to be key intermediates.This reaction system was applicable to the one-pot syntheses of isoxazole derivatives 4 and 5 in the presence of dipolarophiles via a cycloaddition.
- Moriya, Osamu,Takenaka, Hideo,Iyoda, Masaichi,Urata, Yoshikiyo,Endo, Takeshi
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p. 413 - 418
(2007/10/02)
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- (Nitroaryl)sulfinyl-Substituted Allenes. Novel and Convenient Propargyl Alcohol Synthons in 4 + 2 Cycloaddition Chemistry
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(Nitroaryl)sulfinyl-substituted allenes are conveniently prepared by treating propargyl alcohol or methyl 3-hydroxy-2-butynoate with a (nitroaryl)sulfenyl chloride and triethylamine.These activated allenes undergo 4 + 2 cycloaddition across the C1C2 α-bond.The initially formed allylic sulfoxide readily undergoes a 2,3-sigmatropic rearrangement to produce a stable sulfenate ester that is easily cleaved with thiophilic reagents.The dienophilic reactivity of the (nitroaryl)sulfinyl-substituted allene is much greater than the corresponding propargyl alcohol, and the cycloaddition also proceeds with high regioselectivity.The Diels-Alder reaction of propadiene with Danishefsky's diene affords meta-substituted benzyl alcohols in high yield.Reaction of the more highly activated methyl 2--2,3-butadienoate with Danishefsky's diene followed by treatment of the resulting sulfenate ester with triethyl phosphite produces substituted phthalides in excellent yield.The (2,4-dinitrophenyl)sulfinyl-substituted allene was found to react smoothly with a variety of nitrones to give sulfenate esters of isoxazolidines.These allenyl sulfoxides correspond to formal equivalents of propargyl alcohol, which itself is too unreactive to undergo Diels-Alder chemistry or 1,3-dipolar cycloaddition with nitrones or nitrile oxides.
- Padwa, Albert,Bullock, William H.,Norman, Bryan H.,Perumattam, John
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p. 4252 - 4259
(2007/10/02)
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