2445-82-1Relevant articles and documents
A novel NHC-catalyzed transformation of 2H-chromene-3-carboxaldehydes to 3-methyl-2H-chromen-2-ones
Nair, Vijay,Sinu,Rejithamol,Seetha Lakshmi,Suresh, Eringathodi
, p. 5511 - 5514 (2011)
An unexpected transformation of 2H-chromene-3-carboxaldehydes to coumarin derivatives, mediated by NHC, is reported.
Copper(I)-Catalyzed 3-Position Methylation of Coumarins by Using Di-tert-butyl Peroxide as the Methylation Reagents
Zhuang, Huan,Zeng, Runsheng,Zou, Jianping
, p. 368 - 372 (2016)
The copper-catalyzed methylation of coumarin by using di-tert-butyl peroxide (DTBP) has been described. The reaction provides direct access to a wide range of 3-methylcoumarins in moderate to good yields. In this procedure, it is noteworthy that DTBP was employed not only as the oxidant, but also as the methyl source. The copper-catalyzed methylation of coumarin by using di-tert-butyl peroxide (DTBP) has been described. The reaction provides direct access to a wide range of 3-methylcoumarins in moderate to good yields. In this procedure, it is noteworthy that DTBP was employed not only as the oxidant, but also as the methyl source.
Facile Synthesis of 3-Methyl-5,6-dihydro-2H-pyran-2-ones and 3-Methylcoumarines under Mild Conditions
Falsone, Gioacchino,Spur, Bernd,Wingen, Peter H.
, p. 763 - 766 (1983)
The synthesis of the 3-methyl-5,6-dihydro-2H-pyran-2-one, 3, 5 and the 3-methylcoumarines 7a-e from the β-hydroxyoxo compounds 1,4,6a-c and the phosphonopropionic acid 2 under Wittig-Horner conditions is described.
Novel one-pot asymmetric cascade approach toward densely substituted enantioenriched α-methylene-γ-lactams
Tan, Yu,Yang, Xiao-Di,Liu, Wen-Jie,Sun, Xing-Wen
, p. 6105 - 6108 (2014)
A novel one-pot asymmetric synthesis of densely substituted α-methylene-γ-lactams in favor of cis-isomer involving Zn-promoted aza-Barbier-type reaction has been well established. A wide array of α-methylene-γ-lactams were obtained in high yields with excellent diastereomeric ratios from 98:2 to >99:1 and good enantioselectivities. The synthetic potential of such α-methylene-γ-lactams was demonstrated by successfully oxidizing the phenol moiety to quinone in quantitative yield.
Visible-Light-Induced C(sp2)-C(sp3) Coupling Reaction for the Regioselective Synthesis of 3-Functionalized Coumarins
Li, Hanjie,Lin, Zhenwei,Lu, Ping,Qiao, Li,Wang, Yanguang,Xie, Jianwei,Zhang, Ke
, p. 9552 - 9562 (2021/07/26)
A photocatalysis strategy for the regioselective synthesis of 3-functionalized coumarins is reported. With visible light irradiation, a direct and regioselective C(sp2)-C(sp3) coupling reaction of 3-(2-hydroxyphenyl)acrylates with ethers or thioethers occurs by using Ru(bpy)3Cl2·6H2O as a photocatalyst and TBHP as an oxidant. The cascade process involves alkenylation of the C(sp3)-H bond of ethers and lactonization, furnishing 3-alkylated coumarins as the final products. This approach is characterized by a broad substrate scope, mild reaction conditions, and simplified operation. The synthesis of 3-alkylated coumarins could be realized by a one-pot procedure, starting from commercially available salicylaldehyde.
Coumarins by Direct Annulation: β-Borylacrylates as Ambiphilic C3-Synthons
Wienhold, Max,Molloy, John J.,Daniliuc, Constantin G.,Gilmour, Ryan
supporting information, p. 685 - 689 (2020/11/30)
Modular β-borylacrylates have been validated as programmable, ambiphilic C3-synthons in the cascade annulation of 2-halo-phenol derivatives to generate structurally and electronically diverse coumarins. Key to this [3+3] disconnection is the BPin unit which serves a dual purpose as both a traceless linker for C(sp2)–C(sp2) coupling, and as a chromophore extension to enable inversion of the alkene geometry via selective energy transfer catalysis. Mild isomerisation is a pre-condition to access 3-substituted coumarins and provides a handle for divergence. The method is showcased in the synthesis of representative natural products that contain this venerable chemotype. Facile entry into π-expanded estrone derivatives modified at the A-ring is disclosed to demonstrate the potential of the method in bioassay development or in drug repurposing.
Regioselective 3-O-Substitution of Unprotected Thiodigalactosides: Direct Route to Galectin Inhibitors
?erveny, Jakub,Bojarová, Pavla,Bumba, Ladislav,K?en, Vladimír,Pelantová, Helena,Petrásková, Lucie,Spiwok, Vojtěch,Va?í?ek, Tomá?,Vrbata, David
supporting information, p. 9620 - 9631 (2020/08/05)
The synthesis of tailored bioactive carbohydrates usually comprises challenging (de)protection steps, which lowers synthetic yields and increases time demands. We present here a regioselective single-step introduction of benzylic substituents at 3-hydroxy groups of β-d-galactopyranosyl-(1→1)-thio-β-d-galactopyranoside (TDG) employing dibutyltin oxide in good yields. These glycomimetics act as inhibitors of galectins—human lectins, which are biomedically attractive targets for therapeutic inhibition in, for example, cancerogenesis. The affinity of the prepared glycomimetics to galectin-1 and galectin-3 was studied in enzyme-linked immunosorbent (ELISA)-type assays and their potential to inhibit galectin binding on the cell surface was shown. We used our original in vivo biotinylated galectin constructs for easy detection by flow cytometry. The results of the biological experiments were compared with data from molecular modeling with both galectins. The present work reveals a facile and elegant synthetic route for the preparation of TDG-derived glycomimetics that exhibit differing selectivity and affinity to galectins depending on the choice of 3-O-substitution.