Rhodium(III)-Catalyzed Regioselective Decarboxylative Cyclization for the Synthesis of 4<i>H</i>-Furo[3,2-<i>c</i>]chromen-4-one Derivatives
作者:Dandan Zha、Hongji Li、Shiqing Li、Lei Wang
DOI:10.1002/adsc.201600974
日期:2017.2.2
This contribution describes a regioselective cyclization of hypervalent iodine reagents (HIR) with propiolic acids in the presence of a rhodium catalyst. The mild decarboxylation can tolerate a wide range of groups and generates 4H‐furo[3,2‐c]chromen‐4‐one derivatives in good isolated yields.
该贡献描述了在铑催化剂存在下用丙酸对高价碘试剂(HIR)的区域选择性环化。轻度的脱羧可以耐受广泛的基团,并以良好的分离产率生成4 H-呋喃[3,2 - c ] chromen-4-one衍生物。
Design, synthesis and biological evaluation of tanshinone IIA-based analogues: Potent inhibitors of microtubule formation and angiogenesis
We report the structural optimization of tanshinone IIA, a natural product which possesses anti-tumor properties but low water-solubility, weak antiproliferative activity and poor PK properties. A new series of ring A/C/D modified tanshinone analogues were synthesized and studied for their antiproliferative capacities against six human cancer cell lines. SAR study revealed that ring A cleavage of tanshinone
A novel and efficient procedure for the synthesis of furo[3,2-c]coumarins from readily available 4-oxohydrocoumarins and alkenes in the presence of a catalytic amount of Pd(CF3COO)2 has been developed.
A New Approach to the Synthesis of 2-Methyl-4<i>H</i>-furo[3,2-<i>c</i>][1]benzopyran-4-ones and 2<i>H</i>,5<i>H</i>-Pyrano[3,2-<i>c</i>][1]benzopyran-5-ones
作者:R. Jagdish Kumar、G. L. David Krupadanam、G. Srimannarayana
DOI:10.1055/s-1990-26933
日期:——
The reaction of various 4-hydroxy-2H-[1]benzopyran-2-ones 1 with allyl bromide and potassium carbonate in acetone yielded the corresponding 4-allyloxy derivatives 2. Claisen rearrangement of 2 gave 3-allyl-4-hydroxy-2H-[1]benzopyran-2-ones 3, which were reacted with sodium hydroxide to give the sodium benzopyranolate salt 4. Oxidative cyclization of 4 with equimolar quantities of dichlorobis(benzonitrile)palladium gave a 1:1 mixture of 2-methyl-4H-furo[3,2-c][1]benzopyran-4-ones 5 and 2H,5H-pyrano[3,2-c]-[1]benzopyran-5-ones 6, in 88-90% combined yield.
Efficient synthesis of dihydrofurans and furans by rhodium(II)-catalyzed reactions of cyclic diazodicarbonyl compounds
作者:Yong Rok Lee、Jung Yup Suk
DOI:10.1016/s0040-4020(02)00118-7
日期:2002.3
An efficient synthesis of dihydrofurans and furans is achieved by rhodium-catalyzed reactions of cyclic diazodicarbonyl compounds with allyl halides. This method provides a rapid entry toward naturally occurring furocoumarin and furophenalenone derivatives.