FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este trabalho descreve a investigaÃÃo fitoquÃmica das raÃzes, folhas e talos de Lippia affinis gracillis H.B.K. (Verbenaceae), popularmente conhecida no Nordeste do Brasil como âalecrim de vaqueiroâ. A anÃlise cromatogrÃfica dos extratos hexÃnico e etanÃlico das raÃzes e folhas de Lippia aff. gracillis permitiu o isolamento e caracterizaÃÃo do lapachenol (1), dos triterpenos friedelinona (2), acetato de epifriedelanil (3), Ãcido 3-acetil oleanÃlico (6) e lantandeno-A (7), das mistura dos esterÃides -sitosterol e estigmasterol (4) e seus glicosÃdeos (5), do Ãcido graxo Ãcido tetraeicosanÃico (8), das quinonas tecomaquinona (9), microfila quinona (10) e 5-hidroxinafto[2,3b]furan-4,9-quinona (11), dos flavonÃides quercetina (12), hispidulina (13) e da 3-metilquercetina (14). O estudo da composiÃÃo quÃmica dos Ãleos essenciais das folhas e talos de Lippia aff. Gracillis por CGL/EM, apresentou pouca similaridade, sendo os constituintes majoritÃrios das folhas o carvacrol (54,4%) (59) e o p-cimeno (10,7%) (53), enquanto que nos talos foram o carvacrol (30,2%) (59) e o biciclogermacreno (16,7%) (63). Com os Ãleos das folhas e talos, o carvacrol e seus derivados metilado e acetilado foram realizados teste para determinaÃÃo das atividades: Larvicida (Aedes aegypti), moluscicida (Biomphalaria glabrata), antimicrobiana e antioxidante. Na determinaÃÃo estrutural dos metabÃlitos secundÃrios isolados, utilizou-se de tÃcnicas espectroscÃpicas como infravermelho e ressonÃncia magnÃtica nuclear de hidrogÃnio e carbono-13, incluindo tÃcnicas bidimensionais (COSY, HMQC e HMBC), e ainda comparaÃÃo com dados espectroscÃpicos de compostos autÃnticos descritos na literatura. / This work describes the phytochemical studies of the roots, leaves and stalks of Lippia affinis gracillis (Verbenaceae), popularly known in the Brazilian northeast as âalecrim de vaqueiroâ. Chromatographic analysis of hexanic and ethanol extracts of the roots and leaves of Lippia aff. gracillis allowed the isolation and characterization of lapachenol (1), of triterpenes friedelinone (2), epifriedelanyl acetate (3), oleanÃlic acid 3-acethyl (6) and lantandene-A (7), of the mixture steroids -sitosterol and stigmasterol (4) and their glycosides (5), of the fatty acid tetraeicosanoic (8), of the quinone tecomaquinone (9), microphyllaquinone (10) and 5-hydroxynaphto[2,3b]furan-4,9-quinone (11) and flavonoids quercetine (12), hispiduline (13) and 3-methylquercetine (14). The chemical composition of essential oils Lippia aff. gracillis was identified by gas chromatography coupled to mass spectrometry (GCL/MS) study from the leaves and stalks presented similarity small, were major constituents from the leaves the carvacrol (54,4%) (59) of the pcymene (10,7%) (53), while that in the stalks were the carvacrol (30,2%) (59) and biciclogermacrene (16,7%) (63). With the essential oils from the leaves and stalks, the carvacrol and derivative methyled and acethyled from the carvacrol had been made the larvicidal activitys (Aedes aegypti), molluscicide (Biomphalaria glabrata), antibacterial and antioxidant. Structures determinations of all compounds had been established on the basis of spectroscopic techniques such as IR, 1D and 2D NMR (COSY, HMQC, HMBC), as well by comparison with the published data for structurally related compounds.