Os óleos essenciais obtidos das folhas e galhos finos de Piper amapense, Piper duckei e Piper bartlingianum foram analisados por GC/MS. Os óleos dessas espécies são constituídos na sua totalidade por sesquiterpenos. Os principais constituintes identificados no óleo de P. amapense foram trans-cariofileno (25,0%), óxido de cariofileno (17,0%) e β-selineno (15,0%). O óleo de P. duckei foi dominado por trans-cariofileno (23,5%), óxido de cariofileno (18,4%), β-eudesmol (9,4%) e ą-eudesmol (9,1%). Os mais importantes componentes encontrados em P. bartlingianum foram ą-cadinol (11,2%), β-elemene (10,5%), ą-muurolol (9,4%), (E)-nerolidol (9,0%).

The essential oils from leaves and thin branches of Piper amapense, Piper ducket and Piper bartlingianum were analysed by GC/MS and all volatile compounds were identified as sesquiterpenes. The main constitutents identified in the oil of P. amapense were trans-caryophyllene (25.0%), caryophyllene oxide (17.0%) and β-selinene (15.0%). The oil of P. duckei was dominated by trans-caryophyllene (23.5%), caryophyllene oxide (18.4%), β-eudesmol (9.4%) and a-eudesmol (9.1%). The major components found in the oil of P. bartlingianum were <x-cadinol (11.2%), p-elemene (10.5%), ą-muurolol (9.4%), (E)-nerolidol (9.0%).

O aroma dos frutos de Licania tomentosa foi obtido por hidrodestilação e extração com pentano, e seus constituintes voláteis identificados através de cromatografia de gás acoplada à espectrometria de massas (CG/EM). Os principais componentes identificados foram l-hexanol (11,1%), 4-heptanol (10,5%), butanoato de 3-metilbutila (7,4%), hexanal (7,1%) e mirceno (6,4%).

The aroma of Licania tomentosa was obtained by hydrodistillation and extraction with pentane and their volatiles constituents were identified by gas chromatography - mass spectrometry (GC/MS). The main components identified were 1-hexanol (11.1%), 4-heptanol (10.5%), 3-methylbutyl butanoate (7.4%), hexanal (7.1%) and myrcene (6.4%).

Piranojacareubina;l,5-diidroxi-6',6'-dimetil-2H-pirano(2',3':6,7)-6",6"-dimetil-2H,4H(2",3":2,3)xantona e uma xantona inédita l,6-diidroxi-5-metoxi-6',6'-dimetil-2H-pirano(2',3':3,2)-7-(3,3-dimetilprop-2-enil) xantona foram isoladas do extrato etéreo da casca da raiz de Rheedia acuminata além de friedelina e friedelanol.

Pyranojacareubin; 1,5-dihydroxy-6',6'-dimethyl-2H-pyran(2',3':6,7) -6",6"-dim-ethyI-2H,4H-pyran(2",3":2,3)xanthone and a new xanthone l,6-dihydroxy-5-methoxy-6',6'-dim-ethyl-2H-pyran(2',3':3,2)-7-(3,3-dimethylprop-2-enyl)xanthone were isolated from the ether extract of the root bark of Rheedia acuminata together with friedelin and friedelanol.