A synergetic role of Aegle marmelos fruit ash in the synthesis of biscoumarins and 2-amino-4H-chromenes
作者:Rupesh C. Patil、Sachinkumar K. Shinde、Uttam P. Patil、Appasaheb T. Birajdar、Suresh S. Patil
DOI:10.1007/s11164-020-04367-6
日期:2021.4
Abstract A dry rind of Aegle marmelos (bael) fruit ash as a synergetic alternative material to an expensive, toxic and corrosive catalysts for the synthesis of biscoumarins and 2-amino-4H-chromenes at ambient temperature in water is reported. The spectroscopic evidence from EDX, FTIR, XRD and SEM analysis of bael fruit ash supports the presence of metal oxides, carbonates and hydroxides which are intensely
Black yet green: A heterogenous carbon-based acid catalyst for the synthesis of biscyclic derivatives under eco-friendly conditions
作者:Pankaj Teli、Ayushi Sethiya、Shikha Agarwal
DOI:10.1007/s11164-021-04622-4
日期:2022.2
green protocol has been described for the synthesis of biscoumarin and bisdimedone derivatives via one-pot Knoevenagel–Michael reaction of aromatic aldehydes with 4-hydroxycoumarin and dimedone, respectively. This approach has defined a new way of synthesizing products (4a-i and 5a-i) in high yields using carbon sulfonic acid as a heterogeneous solid acid catalyst. All the reactions have been executed
Synthesis of bis-coumarins over acetic acid functionalized poly(4-vinylpyridinum) bromide (APVPB) as a green and efficient catalyst under solvent-free conditions and their biological activity
AbstractIn this work, acetic acid functionalized poly(4-vinylpyridinum) bromide as a green and reusable catalyst was successfully tested on the synthesis of various bis-coumarins undersolvent-freeconditions. In addition, antioxidant and anti-inflammatory activities of the synthesized bis-coumarins were in vitro screened by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and formalin-induced
Chickpea leaf exudates (CLE) mediated Knoevenagel–Michael reactions for the synthesis of diketodiols and biscoumarins
作者:Rupesh C. Patil、Dnyandev N. Zambare、Shashikant A. Damate、Ashutosh A. Jagdale、Snehali R. Mali、Sachinkumar K. Shinde、Suresh S. Patil
DOI:10.1007/s11164-022-04707-8
日期:2022.5
A green, highly efficient, and eco-friendly protocol for Knoevenagel–Michael addition reaction is reported in Chickpea leaf exudates (CLE) as a naturally sourced biosurfactant. The reactions between dimedone/4-hydroxycoumarins and a variety of aryl aldehydes were carried out in presence of CLE to afford diketodiols/biscoumarins. The synthetic pathway complies with several key requirements of green chemistry principles such as the employment of natural feedstock as green reaction media, ambient temperature, atom economy along with natural biosurfactant type Bronsted acids, and recyclable and biodegradable catalyst which led to a 28-fold increase in molar efficiency versus industrial standard protocols. Its dynamic phase is confirmed by the optical microscopy technique and critical micelle concentration measurement. The notable advantages of the present protocol were simple work-up procedure, high yield within short reaction time, easy separation of products, avoiding tedious column chromatography thus making the protocol environmentally friendly, sustainable, and economical.
Benzylidene-bis-(4-Hydroxycoumarin) and Benzopyrano-Coumarin Derivatives: Synthesis, 1H/13C-NMR Conformational and X-ray Crystal Structure Studies and In Vitro Antiviral Activity Evaluations
We report on the synthesis of 4-hydroxycoumarin dimers 1–15 bearing an aryl substituent on the central linker and fused benzopyranocoumarin derivatives 16–20 and on their in vitro broad anti-DNA and RNA virus activityevaluations. The chemical identities and structure of compounds 1–20 were deduced from their homo- and heteronuclear NMR measurements whereas the conformational properties of 5, 14 and