ABSTRACT
Role of synthetic coordination chemistry in pharmaceutical science is expeditiously increased due to its sundry relevances in this field. The present review endows the synthesized macrocyclic complexes of transition metal ions containing isatin and its derivatives as ligand precursors, their characterization and their copious pharmaceutical applications. Isatin (1H-Indole-2,3-dione) is a protean compound (presence of lactam and keto moiety permits to change its molecular framework) that can be obtained from marine animals, plants, and is also found in mammalian tissues and in human fluids as a metabolite of amino acids. It can be used for the synthesis of miscellaneous organic and inorganic complexes and for designing of drugs since it has remarkable utility in pharmaceutical industry due to its wide range of biological and pharmacological activities, for instance anti-microbial, anti-HIV, anti-tubercular, anti-cancer, anti-viral, anti-oxidant, anti-inflammatory, anti-angiogenic, analgesic activity, anti-Parkinson's disease, anti-convulsant etc. This review provides extensive information about the latest methods for the synthesis of isatin or its substituted derivatives based macrocyclic complexes of transition metals and their plentiful applications in medicinal chemistry.
ABSTRACT
As a sequel to our recent study on the oxidation by O2, i. e., autoxidation of dissolved hydrogen sulfide, H2S, in aqueous medium, we present here the results of a similar study in rain water medium. The rainwater sampling was done sequentially for four years (2016-2019). In all 67 samples of rainwater were collected on event basis during monsoon period (June-October) in and around the Campus of University of Rajasthan, Jaipur (26°50Ì N-75°52Ì E), which is situated in a semi-arid region adjacent to the Thar Desert in the North-Western part of the India having an annual average rainfall of 54 cm. ICP-MS technique was used in the analysis of rainwater and more than 30 metals were detected, which included transition metals, rare earths, less common metals. Beryllium, vanadium, silver, selenium, manganese, cerium, gallium, yttrium, barium, cesium, copper, rubidium, arsenic, lanthanum, cadmium, lead, uranium and bismuth were common to all rain water samples.H2S oxidation by dissolved oxygen was studied in rainwater as well as in laboratory water media for comparison. The kinetics rate law was: -d[O2]/dt = k1K1[H+][S][O2]t/( [H+]2 + K1[H+] + K1K2), where K1 is first dissociation constant of H2S and k1 is the rate constant for the dominant reaction step:HS- + O2 â products.
