Chinna Rajesh | University of Delhi (original) (raw)

Papers by Chinna Rajesh

Research paper thumbnail of Nano hydromagnesite as a catalyst and catalyst support for stabilization of Cu(0) and Pd(0) for green and sustainable organic synthesis

Journal of Nanomedicine & Nanotechnology, Jan 2, 2015

Research paper thumbnail of Improved synthesis of natural ester sintenin and its analogues via Wittig reaction†

Department of Chemistry, University of Delhi, Delhi-110 007, India <em>E-mail</em>: d... more Department of Chemistry, University of Delhi, Delhi-110 007, India <em>E-mail</em>: dsrawat@chemistry.du.ac.in Fax: 91-11-27667501 <em>Manuscript received 10 June 2013, accepted 13 June 2013</em> The synthesis of a cytotoxic natural ester sintenin (7a) and twenty eight of its analogues including. nitrogen-containing heterocyclic indole moiety (7b-7t), saturated (10a-10d) and unsaturated (10e-10h) amides were earned out by convenient route via one-pot Wittig reaction in aqueous medium with improved yield. A systematic structure activtiy relationship of sintenin ester was designed by chemically modified derivatives in order to get better cytotoxictty.

Research paper thumbnail of CCDC 838496: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Research paper thumbnail of Amino-quinoline based hybrids and uses thereof

Described herein are aminoqunoline and aminoacridine based hybrids, pharmaceutical compositions a... more Described herein are aminoqunoline and aminoacridine based hybrids, pharmaceutical compositions and medicaments that include such aminoquinoline and aminoacridine based hybrids, and methods of using such compounds for diagnosing and/or treating infections, neurodegerative diseases or disorderes, inflammation, inflammation associated diseases and disorders, diseases or disorders that are treatable with dopamine agonists such as the restless leg syndrome

Research paper thumbnail of RGO/ZnO Nanocomposite: An Efficient, Sustainable, Heterogeneous, Amphiphilic Catalyst for Synthesis of 3-Substituted Indoles in Water

ACS Sustainable Chemistry & Engineering, 2015

A nanocomposite consisting of reduced graphene oxide and zinc oxide nanoparticles (RGO/ZnO) with ... more A nanocomposite consisting of reduced graphene oxide and zinc oxide nanoparticles (RGO/ZnO) with unique structural features was developed as an efficient sustainable amphiphilic heterogeneous catalyst for the synthesis of various 3-substituted indoles in water. The catalyst was recycled six times without significant loss of the catalytic activity. The higher environmental compatibility and sustainability factors such as smaller E-factor and higher atom economy make the

Research paper thumbnail of Ethylenediammonium diformate (EDDF) in PEG600: an efficient ambiphilic novel catalytic system for the one-pot synthesis of 4H-pyrans via Knoevenagel condensation

Research paper thumbnail of Functionalized superparamagnetic Fe3O4 as an efficient quasi-homogeneous catalyst for multi-component reactions

RSC Adv., 2014

Tetrabutylammonium valinate [NBu4][Val] ionic liquid functionalized Fe3O4 NPs (VSF) was used as a... more Tetrabutylammonium valinate [NBu4][Val] ionic liquid functionalized Fe3O4 NPs (VSF) was used as an efficient “quasi-homogeneous” catalyst for multi-component synthesis of 1,4-dihydropyridines and 2-amino-4-(indol-3-yl)-4H-chromenes at room temperature.

Research paper thumbnail of Catalyst-free, ethylene glycol promoted one-pot three component synthesis of 3-amino alkylated indoles via Mannich-type reaction

Tetrahedron Letters, 2014

ABSTRACT A facile protocol, using ethylene glycol as a recyclable promoting medium for the three ... more ABSTRACT A facile protocol, using ethylene glycol as a recyclable promoting medium for the three component reaction of indoles, aldehydes, and amines to form 3-aminoalkylated indoles, is developed.

Research paper thumbnail of Novel 4-Aminoquinoline-Pyrimidine Based Hybrids with Improved in Vitro and in Vivo Antimalarial Activity

ACS Medicinal Chemistry Letters, 2012

A class of hybrid molecules consisting of 4aminoquinoline and pyrimidine were synthesized and tes... more A class of hybrid molecules consisting of 4aminoquinoline and pyrimidine were synthesized and tested for antimalarial activity against both chloroquine (CQ)-sensitive (D6) and chloroquine (CQ)-resistant (W2) strains of Plasmodium falciparum through an in vitro assay. Eleven hybrids showed better antimalarial activity against both CQ-sensitive and CQ-resistant strains of P. falciparum in comparison to standard drug CQ. Four molecules were more potent (7−8fold) than CQ in D6 strain, and eight molecules were found to be 5−25-fold more active against resistant strain (W2). Several compounds did not show any cytotoxicity up to a high concentration (60 μM), others exhibited mild toxicities, but the selective index for the antimalarial activity was very high for most of these hybrids. Two compounds selected for in vivo evaluation have shown excellent activity (po) in a mouse model of Plasmodium berghei without any apparent toxicity. The X-ray crystal structure of one of the compounds was also determined.

Research paper thumbnail of Translation of a Protease Turnover Assay for Clinical Discrimination of Mucinous Pancreatic Cysts

Diagnostics

The classification of pancreatic cyst fluids can provide a basis for the early detection of pancr... more The classification of pancreatic cyst fluids can provide a basis for the early detection of pancreatic cancer while eliminating unnecessary procedures. A candidate biomarker, gastricsin (pepsin C), was found to be present in potentially malignant mucinous pancreatic cyst fluids. A gastricsin activity assay using a magnetic bead-based platform has been developed using immobilized peptide substrates selective for gastricsin bearing a dimeric rhodamine dye. The unique dye structure allows quantitation of enzyme-cleaved product by both fluorescence and surface enhanced Raman spectroscopy (SERS). The performance of this assay was compared with ELISA assays of pepsinogen C and the standard of care, carcinoembryonic antigen (CEA), in the same clinical sample cohort. A retrospective cohort of mucinous (n = 40) and non-mucinous (n = 29) classes of pancreatic cyst fluid samples were analyzed using the new protease activity assay. For both assay detection modes, successful differentiation of m...

Research paper thumbnail of Hydromagnesite as an Efficient Recyclable Heterogeneous Solid Base Catalyst for the Synthesis of Flavanones, Flavonols and 1,4-Dihydropyridines in Water

Advanced Synthesis & Catalysis, 2013

Research paper thumbnail of Au-Cu@PANI Alloy Core Shells for Aerobic Fibrin Degradation under Visible Light Exposure

ACS Applied Bio Materials

Research paper thumbnail of Development of magnesium oxide–silver hybrid nanocatalysts for synergistic carbon dioxide activation to afford esters and heterocycles at ambient pressure

Green Chemistry

Multi-metallic hybrid nanocatalysts consisting of a porous metal oxide host and metal satellite g... more Multi-metallic hybrid nanocatalysts consisting of a porous metal oxide host and metal satellite guests serve as a heterogeneous interface for multi-step transformations of divergent and energy-challenging substrates.

Research paper thumbnail of Renewable RGO@CuI nanocomposites for redox triggered single electron transfer (SET) reaction under aerobic and anaerobic conditions

Research paper thumbnail of Designing Synergistic Nanocatalysts for Multiple Substrate Activation: Interlattice Ag–Fe3O4 Hybrid Materials for CO2-Inserted Lactones

Research paper thumbnail of Magnetically recoverable Ni@CuI hybrid nanocatalysts to afford spiropyrroline heterocycles from ketoximes and alkenes

Asian Journal of Organic Chemistry

Research paper thumbnail of Reduced Graphene Oxide Supported Copper Oxide Nanocomposites from a Renewable Copper Mineral Precursor: A Green Approach for Decarboxylative C(sp3)–H Activation of Proline Amino Acid To Afford Value-Added Synthons

ACS Sustainable Chemistry & Engineering

Research paper thumbnail of CuO@Fe2O3 catalyzed C1-alkynylation of tetrahydroisoquinolines (THIQs) via A3 coupling and its decarboxylative strategies

New J. Chem.

C1-alkynylation of tetrahydroisoquinoline (THIQ) with wide substrate scope was achieved via A3 co... more C1-alkynylation of tetrahydroisoquinoline (THIQ) with wide substrate scope was achieved via A3 coupling strategy from the reaction among THIQ, aldehydes and alkynes using CuO@Fe2O3 as a nanocatalyst under green reaction conditions.

Research paper thumbnail of Decarboxylative Coupling Strategy To Afford N-Heterocycles Driven by Silica-Nanosphere-Embedded Copper Oxide (Cu@SiO2-NS)

ACS Sustainable Chemistry & Engineering

Research paper thumbnail of CuO/Fe2O3 NPs: robust and magnetically recoverable nanocatalyst for decarboxylative A3 and KA2 coupling reactions under neat conditions

Tetrahedron Letters, 2016

CuO/Fe 2 O 3 NPs were found to be robust, green and sustainable nanocatalysts for the synthesis o... more CuO/Fe 2 O 3 NPs were found to be robust, green and sustainable nanocatalysts for the synthesis of trisub-stituted propargylamines by the reaction of propiolic acid, secondary amines and aldehydes via decar-boxylative A3 coupling reaction under solvent free conditions. Further, we explored the wide applicability of the present methodology by replacing the more reactive aldehydes with less reactive ketones to afford the tetrasubstituted propargylamines via decarboxylative KA2 reaction. The present method showed several advantages such as usage of magnetically recoverable with six times recyclability of nanocatalyst, follows green chemistry principles including low E-factor and high atom economy for the A3 and KA2 reactions as well as high turnover numbers through easy catalyst recycling.

Research paper thumbnail of Nano hydromagnesite as a catalyst and catalyst support for stabilization of Cu(0) and Pd(0) for green and sustainable organic synthesis

Journal of Nanomedicine & Nanotechnology, Jan 2, 2015

Research paper thumbnail of Improved synthesis of natural ester sintenin and its analogues via Wittig reaction†

Department of Chemistry, University of Delhi, Delhi-110 007, India <em>E-mail</em>: d... more Department of Chemistry, University of Delhi, Delhi-110 007, India <em>E-mail</em>: dsrawat@chemistry.du.ac.in Fax: 91-11-27667501 <em>Manuscript received 10 June 2013, accepted 13 June 2013</em> The synthesis of a cytotoxic natural ester sintenin (7a) and twenty eight of its analogues including. nitrogen-containing heterocyclic indole moiety (7b-7t), saturated (10a-10d) and unsaturated (10e-10h) amides were earned out by convenient route via one-pot Wittig reaction in aqueous medium with improved yield. A systematic structure activtiy relationship of sintenin ester was designed by chemically modified derivatives in order to get better cytotoxictty.

Research paper thumbnail of CCDC 838496: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Research paper thumbnail of Amino-quinoline based hybrids and uses thereof

Described herein are aminoqunoline and aminoacridine based hybrids, pharmaceutical compositions a... more Described herein are aminoqunoline and aminoacridine based hybrids, pharmaceutical compositions and medicaments that include such aminoquinoline and aminoacridine based hybrids, and methods of using such compounds for diagnosing and/or treating infections, neurodegerative diseases or disorderes, inflammation, inflammation associated diseases and disorders, diseases or disorders that are treatable with dopamine agonists such as the restless leg syndrome

Research paper thumbnail of RGO/ZnO Nanocomposite: An Efficient, Sustainable, Heterogeneous, Amphiphilic Catalyst for Synthesis of 3-Substituted Indoles in Water

ACS Sustainable Chemistry & Engineering, 2015

A nanocomposite consisting of reduced graphene oxide and zinc oxide nanoparticles (RGO/ZnO) with ... more A nanocomposite consisting of reduced graphene oxide and zinc oxide nanoparticles (RGO/ZnO) with unique structural features was developed as an efficient sustainable amphiphilic heterogeneous catalyst for the synthesis of various 3-substituted indoles in water. The catalyst was recycled six times without significant loss of the catalytic activity. The higher environmental compatibility and sustainability factors such as smaller E-factor and higher atom economy make the

Research paper thumbnail of Ethylenediammonium diformate (EDDF) in PEG600: an efficient ambiphilic novel catalytic system for the one-pot synthesis of 4H-pyrans via Knoevenagel condensation

Research paper thumbnail of Functionalized superparamagnetic Fe3O4 as an efficient quasi-homogeneous catalyst for multi-component reactions

RSC Adv., 2014

Tetrabutylammonium valinate [NBu4][Val] ionic liquid functionalized Fe3O4 NPs (VSF) was used as a... more Tetrabutylammonium valinate [NBu4][Val] ionic liquid functionalized Fe3O4 NPs (VSF) was used as an efficient “quasi-homogeneous” catalyst for multi-component synthesis of 1,4-dihydropyridines and 2-amino-4-(indol-3-yl)-4H-chromenes at room temperature.

Research paper thumbnail of Catalyst-free, ethylene glycol promoted one-pot three component synthesis of 3-amino alkylated indoles via Mannich-type reaction

Tetrahedron Letters, 2014

ABSTRACT A facile protocol, using ethylene glycol as a recyclable promoting medium for the three ... more ABSTRACT A facile protocol, using ethylene glycol as a recyclable promoting medium for the three component reaction of indoles, aldehydes, and amines to form 3-aminoalkylated indoles, is developed.

Research paper thumbnail of Novel 4-Aminoquinoline-Pyrimidine Based Hybrids with Improved in Vitro and in Vivo Antimalarial Activity

ACS Medicinal Chemistry Letters, 2012

A class of hybrid molecules consisting of 4aminoquinoline and pyrimidine were synthesized and tes... more A class of hybrid molecules consisting of 4aminoquinoline and pyrimidine were synthesized and tested for antimalarial activity against both chloroquine (CQ)-sensitive (D6) and chloroquine (CQ)-resistant (W2) strains of Plasmodium falciparum through an in vitro assay. Eleven hybrids showed better antimalarial activity against both CQ-sensitive and CQ-resistant strains of P. falciparum in comparison to standard drug CQ. Four molecules were more potent (7−8fold) than CQ in D6 strain, and eight molecules were found to be 5−25-fold more active against resistant strain (W2). Several compounds did not show any cytotoxicity up to a high concentration (60 μM), others exhibited mild toxicities, but the selective index for the antimalarial activity was very high for most of these hybrids. Two compounds selected for in vivo evaluation have shown excellent activity (po) in a mouse model of Plasmodium berghei without any apparent toxicity. The X-ray crystal structure of one of the compounds was also determined.

Research paper thumbnail of Translation of a Protease Turnover Assay for Clinical Discrimination of Mucinous Pancreatic Cysts

Diagnostics

The classification of pancreatic cyst fluids can provide a basis for the early detection of pancr... more The classification of pancreatic cyst fluids can provide a basis for the early detection of pancreatic cancer while eliminating unnecessary procedures. A candidate biomarker, gastricsin (pepsin C), was found to be present in potentially malignant mucinous pancreatic cyst fluids. A gastricsin activity assay using a magnetic bead-based platform has been developed using immobilized peptide substrates selective for gastricsin bearing a dimeric rhodamine dye. The unique dye structure allows quantitation of enzyme-cleaved product by both fluorescence and surface enhanced Raman spectroscopy (SERS). The performance of this assay was compared with ELISA assays of pepsinogen C and the standard of care, carcinoembryonic antigen (CEA), in the same clinical sample cohort. A retrospective cohort of mucinous (n = 40) and non-mucinous (n = 29) classes of pancreatic cyst fluid samples were analyzed using the new protease activity assay. For both assay detection modes, successful differentiation of m...

Research paper thumbnail of Hydromagnesite as an Efficient Recyclable Heterogeneous Solid Base Catalyst for the Synthesis of Flavanones, Flavonols and 1,4-Dihydropyridines in Water

Advanced Synthesis & Catalysis, 2013

Research paper thumbnail of Au-Cu@PANI Alloy Core Shells for Aerobic Fibrin Degradation under Visible Light Exposure

ACS Applied Bio Materials

Research paper thumbnail of Development of magnesium oxide–silver hybrid nanocatalysts for synergistic carbon dioxide activation to afford esters and heterocycles at ambient pressure

Green Chemistry

Multi-metallic hybrid nanocatalysts consisting of a porous metal oxide host and metal satellite g... more Multi-metallic hybrid nanocatalysts consisting of a porous metal oxide host and metal satellite guests serve as a heterogeneous interface for multi-step transformations of divergent and energy-challenging substrates.

Research paper thumbnail of Renewable RGO@CuI nanocomposites for redox triggered single electron transfer (SET) reaction under aerobic and anaerobic conditions

Research paper thumbnail of Designing Synergistic Nanocatalysts for Multiple Substrate Activation: Interlattice Ag–Fe3O4 Hybrid Materials for CO2-Inserted Lactones

Research paper thumbnail of Magnetically recoverable Ni@CuI hybrid nanocatalysts to afford spiropyrroline heterocycles from ketoximes and alkenes

Asian Journal of Organic Chemistry

Research paper thumbnail of Reduced Graphene Oxide Supported Copper Oxide Nanocomposites from a Renewable Copper Mineral Precursor: A Green Approach for Decarboxylative C(sp3)–H Activation of Proline Amino Acid To Afford Value-Added Synthons

ACS Sustainable Chemistry & Engineering

Research paper thumbnail of CuO@Fe2O3 catalyzed C1-alkynylation of tetrahydroisoquinolines (THIQs) via A3 coupling and its decarboxylative strategies

New J. Chem.

C1-alkynylation of tetrahydroisoquinoline (THIQ) with wide substrate scope was achieved via A3 co... more C1-alkynylation of tetrahydroisoquinoline (THIQ) with wide substrate scope was achieved via A3 coupling strategy from the reaction among THIQ, aldehydes and alkynes using CuO@Fe2O3 as a nanocatalyst under green reaction conditions.

Research paper thumbnail of Decarboxylative Coupling Strategy To Afford N-Heterocycles Driven by Silica-Nanosphere-Embedded Copper Oxide (Cu@SiO2-NS)

ACS Sustainable Chemistry & Engineering

Research paper thumbnail of CuO/Fe2O3 NPs: robust and magnetically recoverable nanocatalyst for decarboxylative A3 and KA2 coupling reactions under neat conditions

Tetrahedron Letters, 2016

CuO/Fe 2 O 3 NPs were found to be robust, green and sustainable nanocatalysts for the synthesis o... more CuO/Fe 2 O 3 NPs were found to be robust, green and sustainable nanocatalysts for the synthesis of trisub-stituted propargylamines by the reaction of propiolic acid, secondary amines and aldehydes via decar-boxylative A3 coupling reaction under solvent free conditions. Further, we explored the wide applicability of the present methodology by replacing the more reactive aldehydes with less reactive ketones to afford the tetrasubstituted propargylamines via decarboxylative KA2 reaction. The present method showed several advantages such as usage of magnetically recoverable with six times recyclability of nanocatalyst, follows green chemistry principles including low E-factor and high atom economy for the A3 and KA2 reactions as well as high turnover numbers through easy catalyst recycling.