Research Publications (Applied Sciences)
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Item Sulfonic acid functionalized boron nitride nano materials as a microwave-assisted efficient and highly biologically active one-pot synthesis of piperazinyl-quinolinyl fused Benzo[c]acridine derivatives(Elsevier, 2017) Murugesan, Arul; Gengan, Robert Moonsamy; Anand, KrishnanBoron nitride nano material based solid acid catalyst was found to be an efficient and reusable sulfonic acid catalyst for the synthesis of one-pot Knoevenagel and Michael type reactions in 3, 3-dimethyl-9-(2-(4-methylpiperazin-1-yl) quinolin-3-yl)-3, 4, 9, 10-tetrahydroacridin-1(2H)-one derivatives under mi-crowave irradiation conditions. The catalyst was prepared by mixing boron nitrile and (3-mercaptopropyl) trimethoxysilane. This is simple and safe method for the preparation of solid acid catalysts. The morphological properties of catalyst determined by using FT-IR, XRD, TEM, SEM and Raman spectroscopy. The synthesised catalyst was employed in Knoevenagel and Michael type reactions to synthesise novel piperazinyl-quinolinyl based acridine derivatives. Furthermore the newly-synthesised compounds have been used for molecular docking in DNA binding studies. The method developed in this study has the advantages of good yield, simplicity coupled with safety and short reaction time. Most importantly it was found that the solid acid catalyst can be recycled with only 5% loss of activity.Item Design, synthesis, anticancer, antimicrobial activities and molecular docking studies of novel quinoline bearing dihydropyridines(Elsevier, 2016) Nkosi, S'busiso Mfan'vele; Anand, Krishnan; Anandakumar, S.; Singh, Sanil; Chuturgoon, Anil A.; Gengan, Robert MoonsamyA new series of eight quinoline bearing dihydropyridine derivatives (A1–A8) were synthesized in high yield and in short reaction time by a four component reaction of 2-chloro-3-fomyl quinoline, malononitrile, arylamines and dimethyl acetylenedicarboxylate in the presence of a catalytic amount of triethylamine. The compounds were fully characterized by IR, NMR and GC–MS. These compounds were screened for potential biological activity in an A549 lung cancer cell line and were also evaluated for their antibacterial activities against Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213 whilst their molecular docking properties in an enzymatic system were also determined. Compounds A2, A3, A4 and A8 showed anti-proliferative activity; with A4 having the highest toxicity at 250 μg/mL and A8 has high toxicity at 125, 250 and 500 μg/mL, respectively. Antibacterial results indicated that A4 have significant activity against tested microorganisms at the minimum inhibitory concentration (MIC) values of 32 μg/mL against Pseudomonas aeruginosa and Escherichia coli,and 16μg/mL against Staphylococcus aureus. Docking of A1 with human mdm2 indicated the lowest binding energy (−6.111 Kcal/mol) thereby showing strong affinity of the ligand molecule with the receptor which has been stabilized by strong hydrogen bond interactions in the binding pocket. This confirms that A1 is a better inhibitor for E3 ubiquitin-protein ligase mdm2.Item Influence of epoxy group in 2-pyrrolidonium ionic liquid interactions and thermo-physical properties with Ethanoic or Propanoic acid at various temperatures(ACS Publications, 2016) Vasanthakumar, Arumugam; Redhi, Gan G.; Gengan, Robert MoonsamyIn this present study, the interaction between a carboxylic acid and ionic liquids, in terms of their binary mixtures and corresponding thermo-physical properties, was investigated. Here, the novel ionic liquid (IL) [EPMpyr]+[Cl]− was synthesized, and it has been mixed with ethanoic or propanoic acids. The influence of the epoxy group in this ionic liquid was more strongly affected with the acids, and their physicochemical properties at varied temperatures are discussed in term of density (ρ), viscosity (η), speed of sound (u), and refractive index (n) measurements. The density (ρ), speed of sound (u), viscosity (η), and refractive index (n) of the IL, ethanoic acid, propanoic acid, and their corresponding binary mixtures {[([EPMpyr]+[Cl]− (1) + ethanoic or propanoic acid (2)} have been measured at T = (293.15–313.15) K and at P = 0.1 MPa. The theoretical thermodynamic properties of excess molar volumes (VmE), isentropic compressibility (ks), deviation in isentropic compressibility (Δks), and intermolecular free length (Lf) are calculated using experimental density and speed of sound data. The VmE and Δks values for both binary mixtures were found to be negative over the entire mole fraction range of composition at all the investigated temperatures. These results suggest the existence of specific interactions between components in the molecules. The experimental data could be helpful to understand the molecular interactions between the IL and carboxylic acid combinations. The experimental data were fitted to the Redlich–Kister polynomial equation.Item Synthesis and characterization of 2′,3′-epoxy propyl-N-methyl-2-oxopyrrolidinium salicylate ionic liquid and study of its interaction with water or methanol(Royal Society of Chemistry, 2016) Vasanthakumar, Arumugam; Bahadur, Indra; Redhi, Gan G.; Gengan, Robert MoonsamyImportant physico-chemical properties of ionic liquids (ILs) can be manipulated by adjusting the nature of the cation or anion. These properties are exploited in applications such as organic synthesis, catalysis and electrochemical processes to mention a few. In this work, the novel pyrrolidone ionic liquid N-(2′,3′-epoxypropyl)-N-methyl-2-oxopyrrolidinium salicylate [EPMpyr]+[SAL]− was synthesized using two steps and characterized. The temperature dependent density and speed of sound for ionic liquid, methanol, water, and their corresponding binary mixtures of {IL (1) + methanol or water (2)} were measured over the entire range of mole fractions at temperatures from T = (293.15 to 313.15) K in steps of 5 K, under atmospheric pressure. The calculated thermodynamic properties such as excess molar volume VEm, isentropic compressibility ks, intermolecular free length Lf, and deviation in isentropic compressibility Δks, were derived from the investigated density and speed of sound data. The resulting experimental data for excess molar volumes VEm, intermolecular free length Lf, and deviation in isentropic compressibility Δks, were well fitted to the Redlich–Kister polynomial equation. The effect of temperature and concentration on thermophysical properties was also provided.Item Cobalt boron nitride : a novel heterogeneous catalyst for the synthesis of medicinally important α-amino quinoline phosphonates(Taylor and Fancis, 2016) Sureshkumar, M; Anand, Krishnan; Muthu, T.; Gengan, Robert MoonsamyA novel cobalt supported on boron nitride (CoBNT) heterogeneous catalyst for the synthesis of α-amino quinoline phosphonates (AQPs) is reported in the present work. The CoBNT was synthesised by simply mix-ing boron nitride in a solution of cobalt acetate, under an inert atmosphere for 7 d followed by filtration; the yield was 94%. It exhibited excellent catalytic properties for the synthesis of 16 novel AQPs in a one pot mixture containing 2-methoxy 3-formyl quinoline, aniline derivatives and diethyl phosphite. Reactions were rapid, products were easily worked-up and were obtained in more than 90% yield. The CoBNT also exhibited higher catalytic activity than conventional catalysts and was re-used five times without significant decrease in catalytic activity.Item Biosynthesis of palladium nanoparticles by using Moringa oleifera flower extract and their catalytic and biological properties(Elsevier, 2016) Anand, Krishnan; Tiloke, Charlette; Phulukdaree, Alisa; Ranjan, B.; Chuturgoon, Anil A.; Singh, S.; Gengan, Robert MoonsamyThe biosynthesis of nanostructured biopalladium nanoparticles (PdNPs) from an aqueous solution of crystalline palladium acetate is reported. For the synthesised PdNPs in solution, an agroforest biomass waste petal of Moringa oleifera derived bis-phthalate was used as natural reducing and biocapping agents. Continuous absorp-tion in the UV region and subsequent brown colour change confirmed the formation of PdNPs. A strong surface plasmon peak for PdNPs occurred at 460 nm. PdNPs were characterized by SEM with EDX, FTIR, TEM and DLS. The chemical composition of the aqueous extract was determined by GC–MS coupled with FTIR and 1NMR. The cat-alytic degradation effect by PdNPs on industrial organic toxic effluents p-nitrophenol (PNP) and methylene blue dye was monitored by UV Spectroscopy. On the other hand PdNPs catalysed the base mediated suzuki coupling reaction for biphenyl synthesis, in water. Moreover, PdNPs were found to be reusable catalysts. Toxicity studies of PdNPs showed that the death of brine shrimp to be b50%. Therefore, PdNPs displayed potential for further anti-cancer studies via tumour cell lines. The in vitro cytotoxicity evaluation of the extract capped nanoparticles was carried out using human lung carcinoma cells (A549) and peripheral lymphocytes normal cells by MTT cell via-bility assay. Also, PdNPs showed antibacterial activity against Enterococcus faecalis among the different tested strains, including Bacillus cereus, Staphylococcus aureus, Esherichia coli and Candida albicans, Candida utilis.Item Moringa oleifera gold nanoparticles modulate oncogenes, tumor suppressor genes, and Caspase-9 splice variants in A549 cells(Wiley Online Library, 2016) Tiloke, Charlette; Phulukdaree, Alisa; Anand, Krishnan; Gengan, Robert MoonsamyGold nanoparticles (AuNP's) facilitate cancer cell recognition and can be manufactured by green synthesis using nutrient rich medicinal plants such as Moringa oleifera (MO). Targeting dysregulated oncogenes and tumor suppressor genes is crucial for cancer therapeutics. We investigated the antiproliferative effects of AuNP synthesized from MO aqueous leaf extracts (MLAuNP) in A549 lung and SNO oesophageal cancer cells. A one‐pot green synthesis technique was used to synthesise MLAuNP. A549, SNO cancer cells and normal peripheral blood mononuclear cells (PBMCs) were exposed to MLAuNP and CAuNP to evaluate cytotoxicity (MTT assay); apoptosis was measured by phosphatidylserine (PS) externalization, mitochondrial depolarization (ΔΨm) (flow cytometry), caspase‐3/7, −9 activity, and ATP levels (luminometry). The mRNA expression of c‐myc, p53, Skp2, Fbw7α, and caspase‐9 splice variants was determined using qPCR, while relative protein expression of c‐myc, p53, SRp30a, Bax, Bcl‐2, Smac/DIABLO, Hsp70, and PARP‐1 were determined by Western blotting. MLAuNP and CAuNP were not cytotoxic to PBMCs, whilst its pro‐apoptotic properties were confirmed in A549 and SNO cells. MLAuNP significantly increased caspase activity in SNO cells while MLAuNP significantly increased PS externalization, ΔΨm, caspase‐9, caspase‐3/7 activities, and decreased ATP levels in A549 cells. Also, p53 mRNA and protein levels, SRp30a (P = 0.428), Bax, Smac/DIABLO and PARP‐1 24 kDa fragment levels were significantly increased. Conversely, MLAuNP significantly decreased Bcl‐2, Hsp70, Skp2, Fbw7α, c‐myc mRNA, and protein levels and activated alternate splicing with caspase‐9a splice variant being significantly increased. MLAuNP possesses antiproliferative properties and induced apoptosis in A549 cells by activating alternate splicing of caspase‐9. J. Cell. Biochem. 117: 2302–2314, 2016.Item 4-Dihydroxy-3-(indol-2-)-yl-quinoline via substantial methodology-fisher indole synthesis(Heterocyclic Letters, 2016) Pitchai, P.; Nepolraj, A.; Sathiyaseelan, M.; Gengan, Robert MoonsamyFisher indole methodology, a simple application was used to generate indole as a substitution on the quinoline ring. Conventional heating and microwave irradiation was compared. The ease of work up procedure, reduced time and moreover the high yield is exceptional however microwave irradiation presented more advantages.Item Vilsmeier-Haack reaction : a manifest protocol to synthesise bisquinoline(NISCAIR-CSIR, India, 2016-04) Makhanya, Talent Raymond; Pitchai, P.; Gengan, Robert Moonsamy; Mohan, P.S.Synthesis of bisquinolines from methyl anthranilate and ethyl acetoacetate is described. This synthesis has been accomplished in three steps. Vilsmeier-Haack reaction is used as a key tool to assemble bisquinoline. Microwave heating during each step of the reaction gives high yield of products in short reaction times.Item Utility of Michael type addition on the synthesis of pyrimidines and antibacterial studies of 4,6-diaryl-3,4-dihydropyrimidin-2(1H)-ylidene) cyanamides(JOCPR, 2015) Babu, K.; Pitchai, P.; Gengan, Robert MoonsamySynthesis, characterization and antibacterial studies of newer 4,6-diaryl-3,4-dihydropyrimidin-2(1H)-ylidene) cyanamide derivatives are reported. The structures of all the synthesized compounds were elucidated by the value of spectral data; introduced against selective microorganism using disc diffusion method displayed comparatively good proposition.