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BACKGROUND The global use of antibiotics has become a serious concern because of its variety of potential adverse effects when present in the environment. Acute and chronic toxicity, impact on aquatic organisms, disruption of microbial populations, and dissemination into antibiotic-resistant genes have reportedly been linked to pharmaceuticals. Therefore, the aim of this study was to investigate the mechanism of remediation of some selected pharmaceuticals in aqueous medium on ionic liquid modified biomass. RESULTS The mechanism of sorption of pharmaceuticals on biomass and biomass modified with an ionic liquid (IL) was investigated. Kigelia pinnata (KP) was modified with IL to form modified biomass (KP-IL). The pharmaceuticals investigated were ibuprofen (IBU), ketoprofen (KET), ampicillin (AMP) and diclofenac (DCL). Optimum adsorption was at pH 2.5 for AMP and pH 5 for IBU, KET and DCL. Sorption data for all the pharmaceuticals were best described by pseudo-second-order kinetics and the Langmuir adsorption isotherm. Maximum sorption capacities of 251.2, 197.1, 276.8 and 73 mg g−1 were obtained for KET, DCL, IBU and AMP, respectively. CONCLUSION The study showed that KP-IL is a good material for the remediation of pharmaceuticals, and the adsorption capacity was far better than that of the unmodified KP and biomasses previously reported in literature. © 2016 Society of Chemical Industry

A new facile ionic liquid mediated proficient method is developed for the synthesis of structurally new thiazepine and oxazepine derivatives of thiazolidine 2,4-dione. This protocol proceeds through, one-pot three component reaction between fused cyclic ketone, substituted aromatic aldehyde, 2-amino phenol and 2-amino thiobenzene at room temperature to yield structurally new derivatives.

The paucity of information on the occurrence of pharmaceuticals in the environment in African countries led the authors to investigate 8 acidic pharmaceuticals (4 antipyretics, 3 antibiotics, and 1 lipid regulator) in wastewater, surface water, and sediments from the Msunduzi River in the province of KwaZulu-Natal, South Africa, using solid-phase extraction (SPE) and liquid chromatography–mass spectrometry (LC/MS). The method recoveries, limits of detection (LOD), and limits of quantification were determined. The method recoveries were 58.4% to 103%, and the LODs ranged between 1.16 ng/L and 29.1 ng/L for water and between 0.58 ng/g and 14.5 ng/g for sediment. The drugs were all present in wastewater and in most of the surface water and sediment samples. Aspirin was the most abundant pharmaceutical observed, 118 ± 0.82 μg/L in wastewater influent, and the most observed antibiotic was nalidixic acid (25.2–29.9 μg/L in wastewater); bezafibrate was the least observed. The distribution pattern of the antipyretic in water indicates more impact in suburban sites. The solid–liquid partitioning of the pharmaceuticals between sediment and water, measured as the distribution coefficient (log KD) gave an average accumulation magnitude of 10× to 32× in sediments than in water. The downstream distribution patterns for both water and sediment indicate discharge contributions from wastewater, agricultural activities, domestic waste disposal, and possible sewer system leakages. Although concentrations of the pharmaceuticals were comparable with those obtained from some other countries, the contamination of the present study site with pharmaceuticals has been over time and continues at present, making effective management and control necessary. Environ Toxicol Chem 2016;35:36–46. © 2015 SETAC

A simple four-component reaction of aldehydes, malononitrile, isocyanates and cyclic secondary amines yields fully substituted pyrroles by mild heating in water.