From Silylphosphanes and Oxazolones to New Phosphorus Amido-Acids
作者:M. El Mkadmi、M. Lazraq、A. Kerbal、J. Escudie、C. Couret、H. Ranaivonjatovo
DOI:10.1080/10426509808545459
日期:1998.2.1
Silylphosphanes 3 and 4 gave 1,4-additions with the O=C-C=C moiety of oxazolones 1a-e and 2a-f to afford the adducts 5–8. Oxidation or sulfuration of 5–8 followed by hydrolysis led to oxyphosphorus (or thiophosphorus) amido-acids 9–11 and 15, 19, 20 respectively. A great difference was observed in the behaviour of thiophosphane oxides 16 (R = Me) and 17(R = Ph) toward hydrolysis: 16 led directly to
Hepatitis C (HCV) infection is a cause of chronic liver disease such as cirrhosis, carcinoma, or liver failure, and the current therapy is effective in only 50% of patients. Serine proteases, which are present in HCV, are the most studied class of proteolytic enzymes, and are a primary target in the drug development field. In this paper, we describe the synthesis and biological studies of a novel class of peptide mimetic compounds as potential HCV serine protease inhibitors.
Stereoselective, Ruthenium-Photocatalyzed Synthesis of 1,2-Diaminotruxinic Bis-amino Acids from 4-Arylidene-5(4<i>H</i>)-oxazolones
作者:Sonia Sierra、M. Victoria Gomez、Ana I. Jiménez、Alexandra Pop、Cristian Silvestru、Maria Luisa Marín、Francisco Boscá、Germán Sastre、Enrique Gómez-Bengoa、Esteban P. Urriolabeitia
DOI:10.1021/acs.joc.1c03092
日期:2022.3.4
as μ-isomers. The ruthenium complex behaves as a triplet photocatalyst, generating the reactive excited state of the oxazolone via an energy-transfer process. This reactive excited state has been characterized as a triplet diradical 3(E/Z)-1* by laserflashphotolysis (transient absorption spectroscopy). This technique also shows that this excited state is the same when starting from either (Z)- or (E)-oxazolones
( Z )-2-phenyl-4-aryliden-5(4 H )-oxazolones 1在脱氧 CH 2 Cl 2中在 [Ru(bpy) 3存在下于 25 °C 用蓝光 (465 nm) 照射](BF 4 ) 2 (5% 摩尔比)作为三重态光催化剂促进 4-亚芳基部分的 C=C 键的 [2+2] 光环加成,从而允许完全区域和立体选择性形成环丁烷-双(恶唑酮)s 2作为单一立体异构体。环丁烷2已明确表征为 μ-异构体,并包含两个E-恶唑酮以抗-头对头形式。在微反应器中使用连续流动技术可以在 60 分钟内合成环丁烷2 ,而间歇模式需要 24-48 小时。2中的恶唑酮杂环与碱开环得到相应的 1,2-二氨基松香酸双氨基酯3,其也可选择性地以 μ-异构体的形式获得。钌配合物作为三重态光催化剂,通过能量转移过程产生恶唑酮的反应激发态。这种反应激发态已被表征为三重态双自由基3 ( E / Z )-
Functionalized 1,3‐Diaminotruxillic Acids by Pd‐Mediated C–H Activation and [2+2]‐Photocycloaddition of 5(4
<i>H</i>
)‐Oxazolones
作者:Clara Carrera、Antonio Denisi、Carlos Cativiela、Esteban P. Urriolabeitia
DOI:10.1002/ejic.201900548
日期:2019.8.15
C. C. and E. P. U. thank the Gobierno de Aragon–Fondo Social Europeo (Spain, reference group Aminoacidos y Peptidos E19_17R) for financial support and the Servicio General de Apoyo a la Investigacion–SAI, Universidad de Zaragoza. E. P. U. thanks the COST program under the CA15106 (CHAOS, C–H Activation in Organic Synthesis) grant.
CC 和 EPU 感谢 Gobierno de Aragon–Fondo Social Europeo(西班牙,参考组 Aminoacidos y Peptidos E19_17R)提供资金支持,感谢 Servicio General de Apoyo a la Investigacion–SAI,萨拉戈萨大学。EPU 感谢 CA15106(CHAOS,有机合成中的 C–H 激活)资助下的 COST 计划。
Synthesis of 1,2-diaminotruxinic δ-cyclobutanes by BF<sub>3</sub>-controlled [2 + 2]-photocycloaddition of 5(4<i>H</i>)-oxazolones and stereoselective expansion of δ-cyclobutanes to give highly substituted pyrrolidine-2,5-dicarboxylates
作者:Sonia Sierra、Rosa López、Enrique Gómez-Bengoa、Larry R. Falvello、Esteban P. Urriolabeitia
DOI:10.1039/d3ob00284e
日期:——
(465 nm) in the presence of the photosensitizer [Ru(bpy)3](BF4)2 (2.5 mol%) and the Lewisacid BF3·OEt2 (2 equiv.) in deoxygenated methanol at room temperature affords the corresponding 1,2-diaminotruxinic cyclobutane bis-amino esters 2a–2u stereoselectively as the δ-isomer. Characterization of cyclobutanes 2 shows that the photocycloaddition takes place by the coupling of two Z-oxazolones in a head-to-head