agent in aqueous solution. The results indicate that the quinones derived from catechols, participate in Michael addition reactions with 4-hydroxycoumarin to form the 6H-benzofuro[3,2-c][1]benzopyran-6-one derivatives.
在水溶液中存在作为氧化剂的铁氰化钾的情况下,已经研究了原位生成的邻苯并醌与4-羟基香豆素作为亲核试剂的偶联。结果表明,衍生自邻苯二酚的醌参与与4-羟基香豆素的迈克尔加成反应,形成6 H-苯并呋喃[3,2- c ] [1]苯并吡喃-6-衍生物。
O-Heterocycles via Laccase-Catalyzed Domino Reactions with O<sub>2</sub>as the Oxidant
Laccase-catalyzed domino reactions of 4-hydroxy-6-methyl-2H-pyran-2-one or substituted 4-hydroxy-2H-chromen-2-ones with catechols using molecular oxygen as an oxidant afford coumestans and related O-heterocycles with yields ranging from 51% to 99%.
reaction with 4-hydroxy-pyrone/-benzopyrone afforded substituted benzofuran regioisomers whose structures with only two aromatic protons in total prevent a rapid structuralassignment. Based on the evaluation of 1H–13C long-range couplingconstants a rule of thumb could be deduced for an easy and unambiguous differentiation between the possible regioisomers formed. DFT frontier orbital calculations of the
漆酶催化的取代邻苯二酚的氧化,然后与 4-羟基吡喃酮对苯并吡喃酮取代 苯并呋喃区域异构体的结构总共只有两个芳香族质子,阻止了快速的结构分配。根据对1 H – 13 C远程耦合常数的评估,可以推断出经验法则,可以轻松而明确地区分可能形成的区域异构体。反应物的DFT前沿轨道计算提供了一个有趣的工具来解释关键反应的区域选择性。
A one-pot laccase-catalysed synthesis of coumestan derivatives and their anticancer activity
作者:Tozama Qwebani-Ogunleye、Natasha I. Kolesnikova、Paul Steenkamp、Charles B. de Koning、Dean Brady、Kevin W. Wellington
DOI:10.1016/j.bmc.2016.12.025
日期:2017.2
TK10 cancer cell-line. The total growth inhibition, based on the TGI values, of several of the compounds was better than that of etoposide against the melanoma UACC62 and the breast MCF7 cancercelllines. Several compounds, based on the LC50 values, were also more lethal than etoposide against the same cancercelllines. The SAR for the coumestans is similar against the melanoma UACC62 and breast