Sarita Khandelwal

Deep eutectic solvent promoted efficient and environmentally benign four-component domino protocol for synthesis of spirooxindoles

An efficient and environmentally benign one-pot four-component domino protocol has been presented for the synthesis of structurally diverse spirooxindoles spiroannulated with pyrazolopyrimidophthalazines, indenopyrazolophthalazines, chromenopyrazolophthalazines and indazolophthalazines involving the reaction of phthalic anhydride, hydrazine hydrate, isatins and cyclic diketones/diamides in a deep eutectic solvent (choline chloride:urea: 1:2). The present protocol offers some advantages such as operational simplicity with easy workup, shorter reaction times, good to excellent yields with superior atom economy and environmentally benign reaction conditions.

An efficient one pot three-component nanocatalyzed synthesis of spiroheterocycles using TiO2 nanoparticles as a heterogeneous catalyst

An efficient and environmentally benign isocyanide based domino protocol has been presented for the synthesis of structurally diverse spiroheterocycles, spiroannulated with imidazothiazole and imidazothiadiazole, involving the three component reaction of 2-aminobenzothiazole/2-amino-1,3,4-thiadiazole, cyclohexyl/tert-butyl isocyanides and isatines/cyclic carbonyl compounds catalyzed by recyclable and reusable nanocrystalline TiO2.

A simple, efficient and environmentally benign synthetic protocol for the synthesis of spirooxindoles using choline chloride-oxalic acid eutectic mixture as catalyst/solvent system.

An efficient and environmentally benign domino protocol has been presented for the synthesis of structurally diverse spirooxindoles spiroannulated with pyranopyridopyrimidines, indenopyridopyrimidines, and chromenopyridopyrimidines involving three-component reaction of aminouracils, isatins and cyclic carbonyl compounds in deep eutectic solvent (choline chloride-oxalic acid: 1:1) which acts as efficient catalyst and environmentally benign reaction medium. The present protocol offers several advantages such as operational simplicity with easy workup, shorter reaction times excellent yields with superior atom economy and environmentally benign reaction conditions with the use of cost-effective, recyclable, non-toxic and bio-degradable DES as catalyst/solvent.

Synthesis and evaluation of antioxidant and radical scavenging activities of quinolinobenzothiazinones

A new series of structurally diverse quinolinobenzothiazinones has been synthesized with the annulation of heterocyclic structural pharmacophores. The structures of the synthesized compounds were assigned on the basis of their analytical and spectral data. The synthesized quinolinobenzothiazinones were evaluated for their antioxidant (LPO and GSH) and radical scavenging activities (DPPH and ABTS assays).

Efficient and environmentally benign synthetic protocol for the synthesis of structurally diverse annulated pyridopyrimidines

Structurally diverse annulated pyridopyrimidines have been synthesized by an efficient and environmentally benign synthetic protocol involving catalyzed four-component reaction of 2-aminobenzothiazoles with thiophene-2-carbaldehyde and carbonyl compounds in ethanol. Mild reaction conditions, operational simplicity, and structural diversity with excellent yields are some special attractions of the present protocol.

An efficient and environmentally sustainable domino protocol for the synthesis of structurally diverse spiroannulated pyrimidophenazines using erbium doped TiO2 nanoparticles as a recyclable and reusable heterogeneous acid catalyst

An efficient and environmentally sustainable domino protocol has been presented for the synthesis of structurally diverse spiroannulated pyrimidophenazines involving a four component reaction of 2-hydroxynaphthalene-1,4-dione, benzene-1,2-diamine, cyclic ketones and amino derivatives in the presence of erbium doped TiO2 nanoparticles as a recyclable and reusable heterogeneous acid catalyst. The present synthetic protocol features mild reaction conditions with operational simplicity, excellent yield with high purity, short reaction time and high atom economy with the use of a recoverable and reusable environmentally sustainable heterogeneous catalyst.