Malay Ghosh

Highly Accelerated Reactions in a Microwave Ovem: Synthesis of Heterocycles

Efficient synthesis of a wide variety of heterocycles on 0.1 to 200 g scale was conducted in organic solvents in a commercial microwave oven in a few minutes at a low energy level. Erlenmeyer flasks were adequate reaction vessels since neither high pressure nor high temperature were involved. Fast monitoring of synthetic reactions was achieved by tlc separation and transfer of tlc spot material directly to a solids probe of a chemical ionization mass spectrometer. Microwave oven-induced reaction enhancement (MORE) chemistry is not due to thermolysis: one reaction was conducted successfully in a reaction vial encased in a block of ice.

Monomers and Polymers from Nalidixic Acid — Synthesis, Characterization and Hydrolysis Study

Over the past few years, quinolone derivatives, in particular nalidixic acid and its structural analogues have proven themselves as potential antibacterial agents. These compounds are highly effective against gram negative bacteria in addition to their activity against gram positive organisms. The synthesis of polymeric derivatives of quinolone antibacterials and their biological activities are not available in the literature. In order to prepare safer, potential antibacterial agents, we planned to prepare macromolecules containing quinolones as pendent moieties. This paper will report the synthesis of three new monomers and polymers from nalidixic acid. Their characterization and hydrolysis study at pH 7.4 will also be described.

Synthesis and characterization of polymers having -NH-SO-NH-group in the backbone

SummaryA new monomer 4 has been prepared from the reaction of p-phenylenediamine and excess of thionyl chloride. Reaction of 4 with benzidine in NMP or DMF at elevated temperature resulted a new polymer having -NH-SO-NH-functionality in the backbone. The monomer and the polymer have been characterized by elemental analyses and spectroscopic informations.

Polymeric Anticancer Agents — An Overview

Polymeric materials are being widely studied for possible use in drug administration in the treatment of cancer and other diseases. Two main methods exist for using polymers in such medication: controlled release systems, and biologically active polymers. Both systems are reviewed briefly in the general area of cancer chemotherapy.

The Use of Biotechnology Derived Monomers in the Synthesis of New Polymers: Development of Polyesterimides

The applications of polyesterimides as heat resistant material has many advantages over the conventionally used polymers. This paper will summarize our research on the synthesis and characterization of two new polyesterimides from N-(4-carboxyphenyl) trimellitimide [7] and two other monomers, 4,4’-diacetoxybiphenyl [2] and cis-1,2-diacetoxy-3,5-cyclohexadiene [4] respectively. The physical, physicochemical and thermal properties of the polymers have been investigated. The monomers [2] and [4] have been prepared via enzymatic reactions from commercially available inexpensive starting materials followed by acetylation. This shows, in general, the potential of biotechnology on the development of new polymers, and heat resistant polymers in particular.

New Polymer Synthesis: Polymers Possessing Diiminosulfoxide Functionality in the Backbone

Abstract Three new monomers with sulfinylimine functionality have been prepared. They react with appropriate aromatic diamines to give a new class of polymers having the diiminosulfoxide (—NH—SO—NH—) functional group in their backbone. the monomers as well as polymers are characterized by spectral data and elemental analysis. Experiments were carried out to find the effect of reaction time and solvent on the polymerization reaction. the polymers are soluble in electron-donating organic solvents, such as DMF, NMP, and DMAC, and insouble in most nonpolar solvents. They are thermostable up to 200°C, but their stability in the presence of sulfuric acid and aqueous sodium hydroxide is low.

Synthesis and Characterization of Polymers Having Steroid Sex Hormones as Pendent Moieties

Steroids are widely known for their versatile biological activities and they are being used by physicians all over the world since the 1930s. These drugs have some major disadvantages. A large number of polymeric compounds have been found to be efficient as chemotherapeutic agents. This paper describes the synthesis and characterization of two new monomers derived from two steroid sex hormones — estrone and androsterone, and their subsequent polymerization.