Arnaldo F. Imbiriba da Rocha

The neolignans of Licaria canella

Abstract The trunk wood of Licaria canella contains, besides dillapiol and elemicin, the neolignans canellin-A, -B and -C, for which the respective structures of 1-allyl-4,8-dihydroxy-3,5-dimethoxy-7-methyl-6-piperonylbicyclo-[3,2,1]octane; 3a-allyl-4,5-dimethoxy-3-methyl-2-piperonyl-2,3,3a,6,7,7a-hexahydro-6-oxobenzofuran and 1-allyl-4,8-dihydroxy-5-methoxy-7-methyl-6-piperonyl-3-oxobicyclo-[3,2,1] octane are proposed.

Indole alkaloids as systematic markers of the Apocynaceae

Abstract Indole alkaloids can be characterized by skeletal specialization (S), determined upon consideration of their relative position on a biogenetic map and the number of their naturally occurring substitutional derivatives, as well as by oxidation level (O). The mean (S) and (O) for contained alkaloids of a given plant taxon are taken to represent evolutionary advancement parameters, respectively EAs and EAo.A correlation of these EAs/EAo values for tribes of the Apocynaceae-Plumerioideae reveals a chemical gradient, given by gradually increasing EAs and EAo values, to link Carisseae-Alstonieae-Rauvolfieae-Tabernaemontaneae.

An indolinic cryptoalkaloid from Strychnos mattogrossensis

A new indolinic cryptoalkaloid, mattogrossine, has een isolated from the roots and branches of Strychnos mattogrossensis collected near Manaus. Elucidation of its structure is based mainly on 2D NMR studies. Two other indolinic alkaloids were also obtained: strychnobrasiline and 12-hydroxy-11-methoxystrychnobrasiline, and their 13C NMR data are provided.

CONSTITUINTES QUÍMICOS DE GUSTAVIA AUGUSTA L. (LECYTHIDACEAE)

Gustavia augusta is used in the folk medicine against leishmaniosis and showed anti-inflammatory action. The phytochemical studies of the plant stem bark have led to the isolation of (22E)-stigmasta-7,22-dien-3b-ol, 24a(S)-ethyl-5a-colesta-7,trans-22-dien-3-one, D-friedoolean-14-en-3b-ol, D-friedoolean-14-en-3-one and D-friedoolean-14-en-3a-ol along with stigmasterol, a-amyrin, b-amyrin, lupeol, 3a-hidroxi-lupeol and betulinic acid. The structures of these compounds were identified by IR, GC/MS, 1H and 13C NMR spectral analysis and comparison with literature data.

Essential Oil of Croton lanjouwensis Jablonski from Brazilian Amazonian Region

Abstract The essential oil from inflorescence, fruit, bark and leaves of Croton lanjouwensis Jablonski was analyzed by GC/MS. The major constituents found in the leaf oil α-pinene (26.6%) and α-phellandrene (8.5%); in the fruit oil linalool (14.5%) and β-caryophyllene (190%); in the inflorescence oil α-pinene (28.4%) and linalool (26.7%) and in the bark oil α-pinene (72.2%).

9-Methoxygeissoschizol, an alkaloid from bark of strychnos guianensis

The isolation and structural determination of 9-methoxygeissoschizol from the stem bark of Strychnos guianensis is described. Elucidation of its structure is mainly based on NMR studies.

Chemosystematics of Rhabdodendron

Abstract Analysis of Rhabdodendron amazonicum gave two new compounds, 5′-methoxy-3,4,5,3′-tetra- O -methylflavellagic acid and 3,3′-didehydroxy-5- O -methylflavellagic acid, and confirmed the triterpenoid and O -methylflavellagic acid based composition of the Rhabdodendraceae. Chemically this family fits into the Rosiflorae or even better into the Myrtiflorae.

ALCALÓIDES DE TABERNAEMONTANA HETEROPHYLLA VAHL. (APOCYNACEAE)

Dos extratos metanolicos da casca e do lenho da raiz da Tabernaemontana heterophylla Vahl. (Apocynaceae) foram isolados, alem de sitosterol, lupeol e 3—O—acetil—lupeol, seis alcaloides indolicos: coronaridina, vobasina, affinisina, olivacina, voacangina e epiheyneanina.

Lignanas de Strychnos guianensis (Aublet) Mart.

The present communication reports the isolation and identification of three lignans from metanolic root extracts of Strychnos guianensis (Aublet) Mart.: olivil (1), cycloolivil (2) and the unknown derivative cycloolivil carbonate (3). From hexane extracts was identified a long chain fatty acid mixture and the triterpene lupeol. The analyses were based on chromatographic and spectroscopy techniques (IR, MS, GC/MS, 1H-NMR and 13C-NMR, 1D (BB, DEPT 135) and 2D (1H, 1 H-COSY, 1H, 13C-COSY, 1H, 13C-COSY-LR, HMQC, HMBC and NOESY) and comparison with literature data.

A new strychnobrasiline base of Strychnos mattogrossensis.

A new strychnobrasiline derivative, 12-hydroxy-10,11-dimethoxystrychnobrasiline 1 , has been isolated from the stem barks of Strychnos mattogrossensis . Its structure was established by spectroscopy analysis (1D and 2D NMR, MS, IR, UV) and literature data comparison. Two other known indoline alkaloids were also obtained from the heartwood, 12-hydroxy-11-methoxystrychnobrasiline 2 and strychnobrasiline 3 .