Chandrasekaran Praveen

Synthesis, antimicrobial and antioxidant evaluation of quinolines and bis(indolyl)methanes

An improved and practical synthesis of substituted quinolines and bis(indolyl)methanes was achieved under microwave condition using Zn(OTf)(2) as catalyst. The synthesized compounds have been screened for antimicrobial and antioxidant activities.

Practical synthesis, anticonvulsant, and antimicrobial activity of N-allyl and N-propargyl di(indolyl)indolin-2-ones.

An operation friendly protocol for the synthesis of novel di(indolyl)indolin-2-ones via Cu(OTf)(2) catalyzed bis-addition of N-allyl and N-propargyl indole with isatin was developed. This methodology allowed us to achieve the products in excellent yields without requiring purification technique like column chromatography. All the synthesized compounds were evaluated for their in vivo anticonvulsant activity against maximal electroshock test. Six compounds showed maximum activity compared to the standard drug phenytoin. The scope of the new molecules as antimicrobial agents were tested against two bacterial strains (Staphylococcus aureus and Escherichia coli) and one fungal strain (Candida albicans).

Cu(OTf)2 catalyzed three component reaction: Efficient synthesis of spiro[indoline-3,4′-pyrano[3,2-b]pyran derivatives and their anticancer potency towards A549 human lung cancer cell lines

Cu(OTf)2 catalyzed efficient synthesis of spiropyrano[3,2-b]pyran-4(8H)-ones is accomplished via one-pot three component reaction between isatin, kojic acid and active methylenes. This synthetic protocol is operationally simple and affords product with good to excellent yields at a short reaction time. The synthesized compounds were evaluated for their tumor cell growth inhibitory activity against the human lung cancer cell line (A549) and found that 13 compounds exhibited moderate to good anticancer potency. Molecular docking studies were performed for all the synthesized compounds and the results showed that compound 4e showed greater affinity for anaplastic lymphoma kinase (ALK) receptor.

Microwave-assisted one-pot synthesis of benzothiazole and benzoxazole libraries as analgesic agents

AbstractMicrowave-assisted synthesis of benzothiazole and benzoxazole libraries via PIFA promoted cyclocondensation of 2-aminothiophenols/2-aminophenols with aldehydes under one-pot condition in good to excellent yields was achieved. Twenty compounds have been investigated for their analgesic activity and showed moderate to good activity. Graphical AbstractMicrowave-assisted synthesis of benzothiazole and benzoxazole libraries via PIFA promoted cyclocondensation of 2-aminothiophenols/2-aminophenols with aldehydes under one-pot condition in good to excellent yields was achieved. 20 compounds have been investigated for their analgesic activity and showed moderate to good activity.

Gold(III) chloride catalyzed regioselective synthesis of pyrano[3,4-b]indol-1(9H)-ones and evaluation of anticancer potential towards human cervix adenocarcinoma.

A highly regioselective synthesis of pyrano[3,4-b]indol-1(9H)-ones via gold(III) chloride catalyzed cycloisomerization of 3-ethynyl-indole-2-carboxylic acid was achieved in good to excellent yields. These compounds were screened for their in vitro cytotoxicity against human cervical (HeLa) cell lines. Out of ten compounds, three compounds (7d, 7e and 7j) showed comparable proliferation inhibitory activity against the standard drug cisplatin. Compound 7d was found to be the most efficacious with IC(50) value of 0.22μM.

Regioselective synthesis and evaluation of 3-alkylidene-1, 3-dihydroisobenzofurans as potential antidepressant agents

Abstract3-Alkylidene-1,3-dihydroisobenzofurans exhibited moderate antidepressant activity as evaluated by forced swim and tail suspension test methods. Virtual screening was carried out by docking the designed compounds into the serotonin binding sites of arabinase protein to predict the analogue binding mode of the compounds to the SSRIs. Graphical Abstract3-Alkylidene-1,3-dihydroisobenzofurans exhibited moderate antidepressant activity as evaluated by forced swim and tail suspension test methods. Virtual screening was carried out by docking the designed compounds into the serotonin binding sites of arabinase protein to predict the analogue binding mode of the compounds to the SSRIs.

Super acid catalysed sequential hydrolysis/cycloisomerization of o-(acetylenic)benzamides under microwave condition: Synthesis, antinociceptive and antiinflammatory activity of substituted isocoumarins

AbstractSynthesis of isocoumarins and related compounds via triflic acid promoted hydrolysis/cyclization sequence of 2-(alkynyl)benzamides under microwave condition was achieved. The substrate scope of the reaction was broad to include not only aromatic but also polyaromatic and heteroaromatic motifs, thus highlighting the significance of this methodology. One-pot operation, short reaction time, good chemical yields and excellent regioselectivity are the advantages of this protocol. All the synthesized compounds were evaluated for their antinociceptive and antiinflammatory activities using in vivo rodent models. Graphical AbstractSynthesis of isocoumarins via triflic acid promoted sequential hydrolysis/cyclization of 2-(alkynyl)benzamides under microwave condition was achieved. All the synthesized compounds were evaluated for their antinociceptive and antiinflammatory activities using in vivo rodent models.

Zn(OTf)2-catalysed indolylation and pyrrolylation of isatins: Efficient synthesis and biochemical assay of 3,3-di(heteroaryl)oxindoles

AbstractAn efficient and cheap synthetic approach to 3,3-di(indolyl)oxindoles and 3,3-di(pyrrolyl)oxindoles has been developed via Zn(OTf)2 catalysed indolylation and pyrrolylation of isatins. A preliminary biochemical assay of the synthesized molecules in rodent models were performed to estimate the serum glutamate oxaloacetate transaminase and malondialdehyde levels. Graphical AbstractAn efficient and cheap synthetic approach to 3,3-di(indolyl)oxindoles and 3,3- di(pyrrolyl)oxindoles has been developed via Zn(OTf)2-catalysed indolylation and pyrrolylation of isatins. A preliminary biochemical assay of the synthesized molecules in rodent models were performed to estimate the SGOT and MDA levels.

Cu(OTf)2 catalyzed three component strategy for the synthesis of thienopyridine containing spirooxindoles and their cytotoxic evaluation

Synthesis of novel spirooxindoles via a three component reaction of thienopyridines, isatins and malononitriles under copper catalysis was accomplished. This one-pot, room temperature protocol allowed the synthesis of diversely substituted spirooxindoles in good to excellent yields. Cytotoxicity towards COLO320 cells revealed that compound 5v possessing a 2,6-difluorobenzyl group (IC50 of 49.1 μM) was found to be highly potent among the screened compounds. In addition, molecular docking of compound 5v into caspase-3 receptors exhibited the largest binding energy (−10.5 kcal mol−1) compared to other compounds. The formation of a DNA ladder for compound 5v also supports the experimental results.