Efficient synthesis of isoxazolidine-substituted bisphosphonates by 1,3-dipolar cycloaddition reactions
摘要:
Several bisphosphonates bearing a substituted isoxazolidine ring have been synthesized in good yield by direct 1,3-dipolar cyclization reaction, under microwaves catalysis, in the absence of solvent. The method allows the simultaneous incorporation, on the geminal position of the bisphosphonate framework, of a basic nitrogen and of an oxygen atom, as third hook. Hydrophobicity-hydrophilicity of BPs is discussed with the help of distribution coefficients. (C) 2011 Elsevier Ltd. All rights reserved.
Zinc Iodide-Mediated Direct Synthesis of 2,3-Dihydroisoxazoles from Alkynes and Nitrones
作者:Zu-Feng Xiao、Ting-Hui Ding、Sheng-Wei Mao、Xiao-Shan Ning、Yan-Biao Kang
DOI:10.1002/adsc.201600044
日期:2016.6.2
A zinc diiodide (ZnI2)‐mediated directsynthesis of 2,3‐dihydroisoxazoles via a [3+2] cycloaddition reaction of the nitrones and non‐electron‐deficient terminalalkynes has been developed. This method was applied in the formal synthesis of HPA‐12 and aminoglucose.
Synthesis and X-ray study of hexahydro- and tetrahydrophospholo-[2,3-<i>d</i>]isoxazoles, a new class of heterocycles of potential fungicidal activity
作者:Fabrizio Machetti、Beatrice Anichini、Stefano Cicchi、Alberto Brandi、Wanda Wieczorek、K. Michal Pietrusiewicz、Jean-Claude Gehret
DOI:10.1002/jhet.5570330416
日期:1996.7
Hexahydro-, 5b-1 and 6a,f,1 and tetrahydrophospholo[2,3-d]isoxazoles 8, 9 and 10 were synthesized by 1,3-dipolar cycloaddition of nitrones 3b-1 and benzonitrile oxide (4) to 2,3-dihydro-1-phenyl-1H-phosphole 1-oxide (1) and 2,3-dihydro-1-ethoxy-1H-phosphole 1-oxide (2). The structural assignment to the compounds was confirmed by an X-ray study of two compounds of the series 5a and 5m. The compounds
通过将1,3-偶极环3b-1和氧化苄腈(4)进行1,3-偶极环加成反应合成六氢,5b-1和6a,f,1和四氢磷[2,3- d ]异恶唑8、9和10。 3-二氢-1-苯基-1 H-磷酰基1-氧化物(1)和2,3-二氢-1-乙氧基-1 H-磷酰基1-氧化物(2)。通过对5a和5m系列的两种化合物的X射线研究证实了这些化合物的结构归属。该化合物作为杀真菌剂对葡萄小单胞菌表现出良好的活性。葡萄藤上和苹果上的灰葡萄孢菌。化合物5a-d显示出弱至中等的除草剂活性。
Lewis base-catalyzed diastereoselective [3 + 2] cycloaddition reaction of nitrones with electron-deficient alkenes: an access to isoxazolidine derivatives
A Lewis base-catalyzed [3 + 2] cycloadditionreaction of nitrones with electron-deficientalkenes has been achieved under mild reaction conditions, affording various functionalized isoxazolidine derivatives as single diastereomers in moderate to excellent yields.
Novel Prospects of the Acidic Thermal Rearrangement of Spiro[cyclopropane-1,5′-isoxazolidines] toβ-Lactams
作者:Franca M. Cordero、Maria Salvati、Federica Pisaneschi、Alberto Brandi
DOI:10.1002/ejoc.200300595
日期:2004.5
Monocyclic β-lactams were synthesized by a 1,3-cycloaddition/thermal rearrangement process in the presence of a protic acid, starting from methylenecyclopropane derivatives and acyclic nitrones. Five-membered cyclic nitrones failed to give carbapenam structures under the same conditions, affording exclusively the corresponding N-trifluoroacetyl β-amino acid derivatives in the presence of trifluoroacetic