Dr. Elango K.

It is well known that applying green chemistry aspects for organic reactions would reduce the toxicity of chemicals and it reduces the amount of volatile organic solvents too. Thus we have developed a Bronsted acidic 1-pentyl-1,2–4-triazolium methanesulfonate as a room temperature ionic liquid for organic reactions as reaction medium. The same has been employed as organocatalyst for the synthesis of β-Carbonyl Compounds. The present papers reveal the significance of ionic liquids in optimization of reaction condition in terms of equivalence of reagents, impact of solvents and amount of catalyst, synthesis of library of halogen rich β-carbonyl compounds.

Protein denaturation occurs when the secondary and tertiary structures of protein undergo conformational changes and native state of protein is destroyed. The most common observation of the denaturation phenomenon is either coagulation or precipitation of proteins. Since the denaturation processes are not strong enough to break the peptide bonds, the amino acid sequence is not perturbed and hence the primary structure of proteins is not affected and uncoils itself into a random shape. There are variety of reagents and conditions which can protein denaturation, such as urea, temperature, pH, alcohol, heavy metal, etc. Heavy metal salts present in the vicinity of a protein can induce protein denaturation by disturbing the disulfide bond. Heavy metal salts which induce protein denaturation are usually Hg2+, Pb2+, Ag+,Tl+, Cd2+and other metal ions with high atomic weights. The heavy metal salts usually reacts with a protein forming insoluble metal-protein salt. Salts such as silver nitrate are used to prevent gonorrhea infections in the eyes of new born infants. It is also used in treatment of various infection and wounds. The current work will involve the fluorescence spectroscopic studies on protein denaturation induced by heavy metal salts; as reported by the fluorescence probing technique. For this study, we will use bovine serum albumin (BSA) is chosen as the protein. The fluorescent property of Tryptophan (Trp) moiety of BSA can be utilized for the study. It can be understood that in present of silver salt, there is Trp fluorescence quenching and data reveals the denaturation of BSA.

We have designed and synthesized phthalimido labelled peptide nucleic acid (PNA) monomer through N-alkylation of α-amino acid ester with N-bromo ethylphthalimide which was facilitated by using ionic liquids. The alkylated product was condensed with nucleobase such as thymine-1-acetic acid to get the target compound. The labelled-PNA monomer is a new molecule which bears a marker and can be easily prepared in two steps

Introduction The N-heterocyclic compounds have been extensively studied in pharmaceutical industries. Furthermore, syntheses of such compounds employing organo-catalyst have been associated with sustainable technology. Methods The synthesis of new, stable ionic liquids and their catalytic applications in one-pot multicomponent Biginelli reaction is presented. The method provides broad substrate scope, yielding the corresponding 3,4-dihydropyrimidin-2(1H)-ones and 3,4-dihydropyrimidin-2(1H)-thiones, in good to excellent yields, respectively. Results and Conclusion The developed reactions are associated with certain advantages, short reaction time and sustainable conditions. The protocol has advantages eco-friendly procedure, recovery and reusability of catalyst, which showed consistent activity.

A Brønsted acidic 1-ethyl-1,2,4-triazolium phenylsulfonate has been synthesized and characterized. A catalytic study is performed for 1-ethyl-1,2,4-triazolium phenylsulfonate as acid catalyst for a multicomponent reaction of synthesis of series of 3,4-dihydropyrimidin-2(1H)-ones/thiones and their derivatives have been employed and the results were discussed in detail. © 2018 Chemical Publishing Co. All Rights Reserved.

Synthesis of three Brnsted acid-based ionic liquids, namely, 1-ethyl-1,2,4-triazolium triflate (1a), 1-propyl-1,2,4-triazolium triflate (1b) and 1-butyl-1,2,4-triazolium triflate (1c), is described. These ionic liquids have been employed as catalysts for convenient and high-yielding one-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones and 3,4-dihydropyrimidin-2(1H)-thiones, which are Biginelli reaction products. Advantages of the methodology are operational convenience, short reaction times, avoidance of chromatographic purification and non-production of toxic waste. Further, the catalysts are easily recovered and reused without any noticeable diminution in their catalytic activity.

Compound 1-Methyl-3-(2-pyridyl)imidazolium hexafluorophosphate was crystallized in monoclinic system with space group P21/c and unit cell parameters a=7.3740(8) Å, b=15.5931(16) Å, c=10.4787(11) Å, β= 105.3102°, and  ν=1162.12Å3. The obtained solid state structure of 1-Methyl-3-(2-pyridyl)imidazolium hexafluorophosphate shows CH⋯F type weak interactions and was analyzed.

The diacetato-bis(2-methyl-2-propylamine)zinc(II) compound crystallizes in the triclinic system, space group P-1 with unit cell parameters a = 10.0144(10)Å, b = 10.2687(10)Å, c = 10.5149(10)Å. α = 115.184(2)°, β = 97.489(2)°, γ = 114.066(2)°, ν = 830.85(14)Å3. The obtained solid state structure of (tBuNH2)2Zn(OOCCH3)2 shows both inter- and intramolecular NH—O hydrogen bond interactions which are analyzed.

Six different room temperature ionic liquids (RTILs) based on N-methyl or N-isopropyl imidazolium cations with counteranions, such as BF4-, PF6-, and OTf−, have been synthesized by exchanging the counteranions of the corresponding N-methyl or N-isopropylimidazolium bromides using appropriate salts such as NH4BF4, KPF6, and AgOTf. Catalytic amounts of these ionic liquids (ILs) have been used as the reaction medium for the Beckmann rearrangement of oximes to amides in the presence of PCl5. A moderate to good conversion of oximes to amides in all the six ILs was observed.