Several natural compounds have been identified for the treatment of leishmaniasis. Among them are some alkaloids, chalcones, lactones, tetralones, and saponins. The new compound reported here, 7-geranyloxycoumarin, called aurapten, belongs to the chemical class of the coumarins and has a molecular weight of 298.37. The compund was extracted from the Rutaceae species Esenbeckia febrifuga and was purified from a hexane extract starting from 407.7 g of dried leaves and followed by four silica gel chromatographic fractionation steps using different solvents as the mobile phase. The resulting compound (47 mg) of shows significant growth inhibition with an LD 50 of 30 µM against the tropical parasite Leishmania major, which causes severe clinical manifestations in humans and is endemic in the tropical and subtropical regions. In the present study, we investigated the atomic structure of aurapten in order to determine the existence of common structural motifs that might be related to other coumarins and potentially to other identified inhibitors of Leishmania growth and viability. This compound has a comparable inhibitory activity of other isolated molecules. The aurapten is a planar molecule constituted of an aromatic system with electron delocalization. A hydrophobic side chain consisting of ten carbon atoms with two double bonds and negative density has been identified and may be relevant for further compound synthesis.

This paper describes a fault location algorithm for three-terminal transmission lines based on Wavelet Transform (WT). In this work, the Wavelet Transform has been used to analyze the high frequency components of the current and/or voltage signals generated by a fault. This fault location method is based on the traveling wave theory, where, by the processing of the current and/or voltage signals using WT, the propagation time between the fault point and the terminals can be determined.Consequently, the distance of the fault as well as the faulted leg can be easily calculated. This proposal requires data synchronization, which can be made by GPS, and communication links amongst the teed feeders. The results obtained for the algorithm are promising and they demonstrate a highly satisfactory degree of accuracy and applicability of the proposed method.

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