Estudo químico e biológico de Croton regelianus var. matosii (Euphobiaceae)

Abstract

This work describes the phytochemical investigation of Croton regelianus (Euphorbiaceae), with the purpose to isolate and characterize new bioactive secondary metabolites, as well as, to investigate the chemical composition of the leaf essential oils and to evaluate its biological potential. The study of the leaf essential oils from samples collected at two different geographical sites resulted in the identification of 20 components. More than 98% of the chemical composition, exclusively monoterpenes, of each oil was determined. The essential oil and its major component, ascaridole, showed potent activity against the Aedes aegypti and Artemia sp larvae and moderate activity against the nematode Meloidogyne incognita. Both, the essential oil and ascaridole also exhibited potent anticancer activity. The phytochemical investigation of hexane and ethanol extracts from leaves and branch of C. regelianus conducted to the isolation and characterization of ten substances. From the hexane extract of the leaves were isolated triacontanol, phytol, b-sitosterol and (3R, 4R, 6S)-3,6-dihydroxy-1-menthene, while from ethanol extract were isolated the b-sitosterol glycoside. From the hexane extract of branch were isolated the steroidal mixture 6b-hydroxy-campest-4-en-3-one and 6b-hydroxyestigmast-4-en-3-one, and the (4aS,8aS,)-4,4a,8a,9,10,10a-hexahydro-8a-hydroxy-1,1,4a,7-tetramethylphenanthrene-2,6(1H,3H,)-dione. From the ethanol extract was obtained the sesquiterpene 1a-hydroxymethyl-6b-hydroxy-4a-methyl-7b-(1-methylethyl)-4b,11b-epoxy-decahydroazulene and the coumarin cleomiscosine A. The structure of all compounds were elucidated by spectroscopic methods, such as IR, LREIMS, HRESIMS, 1H and 13C NMR, and by comparison with published data for closely related compounds. Even though the cytotoxic properties of all compounds have been tested no one showed any activity.