The conversion of epoxides into dialcohols, ethers and aminoalcohols has drawn a great deal of attention in the studies of synthesis of epoxides. The significance of epoxides lies in the fact that K Barry Sharpless shared the 2001 Nobel prize in Chemistry for his work on asymmetric oxidations with William S Knowles and Ryoji Noyori. Interestingly, the first paper, “Enantioselective Epoxidation of Some Aryl-Aryl a, b-Unsaturated Ketones”, by G Thirunarayanan and G Vanangamudi, reports a highly efficient method of synthesis of epoxy ketones from their E-conformers of substituted styryl ketones using chiral quaternary ammonium bromide-PF6 catalyst. Such kind of phase transfer catalyst can be very useful for the synthesis of highly stereo-selective oxiranes.

Several coumarin derivatives have a wide range of biological activities—antioxidant, anti-inflammatory, anticoagulant, antibacterial, antifungal, and antitumor activities; moreover, these derivatives also show anti-HIV activity. Therefore, coumarin derivatives always remained in the focus areas of research. The biological activity is related to the substituents present on the benzopyran ring. In the second paper, “Synthesis and Spectral Analysis of Coumarin Derivatives”, by H V Upadhyay, H P Pandya, A B Patel and Z M Gadhawala, a method for the synthesis of coumarin derivatives has been described using acetyl coumarin with different substituted aromatic amines, and various derivatives were characterized by IR and NMR studies.

Nanotechnology involves typically 1-100 billionth of meter particles. Physical properties of known elements and materials can change as their surface-to-area ratio is dramatically increased, i.e., when nanoscale sizes are achieved. These remarkable changes in physical properties, such as colloidal properties, solubility and catalytic capacity, are tremendously beneficial in areas of biotechnology, such as medicine and drug delivery. The extremely small size of nanoparticles allows them to penetrate cells and interact with cellular molecules. The third paper, “ImatiniB-Induced Silver Nanoparticle Aggregation Analyzed by Surface Spectroscopic and Microscopic Techniques”, by V Srinivasan, S K Thabasum Sheerin and B Karthikeyan, describes the use of ImatiniB (IB) mesylate, an oncological drug useful for treatment of various types of cancer, to produce nanosilver aggregation.

The Zeolites are regular framework of alumino-silicate structure with symmetrically stacked alumina and silica tetrahedra, which result in an open and stable three-dimensional honeycomb structure, thus making it a highly porous material that allows molecular sieving. Because of their unique porous properties, Zeolites have a number of applications in catalysis, ion exchange and adsorption. For synthetic Zeolites, it is generally required that a process be commercially viable in the global market, and hence conversion of low-grade clay into sodalite is important. The fourth paper, “Conversion of Low-Grade Indian Clays to Zeolite NaA”, by S K Sharma and S S Sambi, describes the preparation of Zeolites and metakaolin using Rajasthan China clays. The results show that their calcium exchange capacity increases at high temperature of calcinations and with increase in alkali ratio. The SEM studies have indicated that the Zeolite formed is Zeolite NaA.

Velocity of ultrasonic sound is a useful and important property, and there is a correlation between sound velocity and chemical structure. In the fifth paper, “Acoustical Studies of Some Derivatives of 4-Amino Benzoic Acid in 1,4-Dioxane and Dimethyl Formamide at 308.15 K”, by Shipra Baluja and Pranav Inamdar, a number of derivatives of 4-amino benzoic acid were prepared and characterized by spectral techniques, and their ultrasonic velocity, density and viscosity were measured in solvents like 1,4-dioxane and Dimethyl Formamide (DMF) as a function of temperature. Solute-solvent interaction of all these bases in both DMF and 1, 4-dioxane solutions was further confirmed by the solvation number (Sn), which is a measure of the structure-forming or structure-breaking tendency of the solute in solution.

The role of poly-a-amino acids in understanding the mechanism of protein denaturation and decoding of genetic code is important. The interactions between surfactants or simple molecules and poly-a-amino acids can provide vital information for the studies of induced conformational changes of proteins. Therefore, a number of investigations have been made on conformational changes of homopolypeptides such as a Poly-L-Lysine (PLL) upon their interactions with ionic surfactants. The sixth paper, “Conformational Studies on Hexamethylenediamine-Bound L-Lysine Oligomers”, by Ajay Kumar, relates conformational studies on hexamethylenediamine (HMDA)-bound e’-benzyloxycarbonyl-L-lysine oligomers and HMDA-L-lysine-bound oligomers as a function of chain length.

Each year, the losses due to corrosion to the manufacturers and consumers are to the tune of millions of dollars; mostly the loss is due to the corrosion of iron and steel, although many other metals may corrode as well. Extensive pitting eventually causes structural weakness and disintegration of the metal. Much of this corrosion damage could be avoided by taking proper care. It is of immense practical importance to study the nature of corrosion behavior and suggest preventive measures. The last paper, “Corrosion Behavior of Medium Carbon Steel in Paint Industrial Effluent”, by T Sasikala and B Ramesh Babu, reports the effect that effluent of paint industries has on Galvanized Iron Pipes (GIPs), which are frequently used in Central Effluent Treatment Plants (CETPs). Most of the GIPs are made of Medium Carbon Steel (MCS). It has also been suggested that the effluents must be treated to reduce the Chemical Oxygen Demand (COD) before releasing them in the environment.

-- Sushama Viladkar
Consulting Editor