Cyclichydroxamicacids can be viewed as effective binders of soluble iron and can therefore be useful moieties for employing in compounds to treat iron overload disease. Alternatively, they are analogs of bacterial siderophores (iron-scavenging metabolites) and can find utility in designing antibiotic constructs for targeted delivery. An earlier described three-component variant of the Castagnoli-Cushman
One-pot synthesis and radical scavenging activity of novel polyhydroxylated 3-arylcoumarins
作者:Ivan Svinyarov、Milen G. Bogdanov
DOI:10.1016/j.ejmech.2014.03.053
日期:2014.5
An unexpected domino rearrangement brought about the development of a novel one-pot procedure for synthesis of coumarins. This protocol allowed the gram-scale synthesis of a variety of polyhydroxylated derivatives 3a–p, from readily available starting materials at a low cost. Based on two proven intermediates, a probable mechanism consisting of boron tribromide induced demethylation/lactone ring o
意外的多米诺骨牌重排带来了一种新的一锅法合成香豆素的方法的发展。该协议允许以低成本从容易获得的起始原料中克级合成多种多羟基化衍生物3a – p。基于两种已证实的中间体,一种可能的机理由三溴化硼诱导的原位脱甲基/内酯开环/消除/异构化/内酯闭环反应序列组成推导形成的3-芳基-3,4-二氢异香豆素-4-羧酸。与用于合成香豆素的常规方法相比,本文提出的方法具有很大的优势,例如条件温和,反应时间短,收率高,后处理步骤简单和最终产物易于分离等。通过光谱方法(1 H NMR,13 C NMR,IR,MS和HRMS)建立了新合成的化合物3a – p的结构,并在体外评估了它们对游离1,1,1-二苯基-2-吡啶二酰肼的自由基清除活性。自由基(DPPH )。获得的结果表明,化合物3g – p具有比自由基抗氧化剂例如trolox,原儿茶酸,咖啡酸和没食子酸更高的自由基清除活性(3.16≤SC 50 [μM]≤6