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A investigacao fitoquimica dos frutos maduros de Solanum caavurana Vell. (Solanaceae) forneceu um novo alcaloide esteroidal do tipo espirosolano, caavuranamida, juntamente com os alcaloides 4-tomatiden-3-ona e 5α-tomatidan-3-ona. Suas estruturas foram elucidadas atraves de metodos espectroscopicos. As atividades antiproliferativa e antimicrobiana para o extrato etanolico e subfracoes provenientes de particao e de extracao acido-base foram investigadas. A caavuranamida apresentou atividade antibacteriana similar ao controle positivo cloranfenicol contra Rhodococcus equi. Phytochemical investigation of the ripe fruits of Solanum caavurana Vell. (Solanaceae) afforded a novel steroidal alkaloid with spirosolane-type skeleton, named as caavuranamide, together with the alkaloids 4-tomatiden-3-one and 5α-tomatidan-3-one. Their structures were elucidated on the basis of spectroscopic methods. The antiproliferative and antimicrobial activities for the ethanolic extract, sub-fractions obtained from partition and acid-base treatment were also evaluated. Caavuranamide showed antibacterial activity similar to the chloramphenicol positive control against Rhodococcus equi.

Phytochemical study of the bark of Guatteria blepharophylla (Mart.) Mart. afforded twelve compounds, namely two sesquiterpenes, caryophyllene oxide (1) and spathulenol (3), one xanthone, lichexanthone (2), a mixture of steroids, β-sitosterol (4), and stigmasterol (5), and seven isoquinoline alkaloids, O-methylmoschatoline (6), lysicamine (7), nornuciferine (8), liriodenine (9), isocoreximine (10), subsessiline (11), and isomoschatoline (12). Their structures were established on the basis of spectroscopic methods. Compounds 1-6, 11 and 12 were reported for the first time in this species. The 13C NMR (nuclear magnetic resonance) data for the compounds 11 and 12 are described for the first time in the literature. The antiproliferative activity against human tumour cell lines and antimicrobial activities were investigated for the major compounds. Compound 9 showed significant activity against cell lines of breast (MCF-7, Michigan Cancer Foundation-7), superior to the positive control doxorubicin. Compound 12 presented antifungal activity similar to the positive control nystatin against Candida albicans.

This report deals with the formal synthesis of deoxynojirimycin using D-glucitol as an inexpensive starting material. Through a sequence of several selective protection/deprotection and nucleophilic substitution reactions, many isopropylidene derivatives were obtained. Formation of an epoxide intermediate and its subsequent ring opening, via intramolecular nucleophilic substitution, leads to the synthesis of heterocyclic 1,5-dideoxy-1,5-diamine-2,3-O-isopropylidene-6-silyl-D-glucitol, which is a precursor of deoxynojirimycin (DNJ). Descrevemos a síntese formal da desoxinojirimicina usando D-glucitol como material de partida economicamente atraente. Através de uma seqüência de reações de proteção e desproteção seletivas e reações de substituição nucleofílica obtivemos diversos intermediários isopropilidênicos. A formação de um epóxido intermediário e sua subseqüente abertura, através de uma reação nucleofílica intramolecular, levou à obtenção do heterociclo 1,5-didesoxi-1,5-diamino-2,3-O-isopropilideno-6 -silila-D-glucitol, que é um precursor da desoxinojirimicina (DNJ).

Four indole alkaloids, 12-methoxy-Na-methyl-vellosimine, demethoxypurpeline, 12-methoxyaffinisine, and 12-methoxy-vellosimine, in addition to picrinine, vinorine, raucaffrinoline, normacusine B, norseredamine, seredamine, 10-methoxynormacusine B, norpurpeline and purpeline, were isolated from the bark or leaf extracts of Rauvolfia bahiensis. # 2002 Published by Elsevier Science Ltd.

First report of alkaloids in the genus Guatteriopsis (Annonaceae) Emmanoel V. Costa , Maria Lucia B. Pinheiro , Francisco A. Marques , Raquel M. Braga , Beatriz Helena L.N. Sales Maia a,* Departamento de Quimica, Universidade Federal do Parana, Centro Politecnico, Jardim das Americas, PO Box 19081, Curitiba, PR 81531-990, Brazil Departamento de Quimica, Universidade Federal do Amazonas, Av. General Rodrigo Otavio Jordao Ramos, 3000, Coroado, Manaus, AM 69077-000, Brazil c Instituto de Quimica, Universidade Estadual de Campinas, PO Box 6154, Campinas, SP 13083-970, Brazil

Transformation of D-glucitol into its 1,6-diazido deriva- tive allowed its conversion into the polyhydroxylated amino- azepane ring in a one-pot reaction using Ph3P and H2O.

Zusammenfassung Les desaminogirollines syn 2′S,3′S et 2′R,3′R ont ete preparees par dedoublement de leurs derives diastereoisomeres. La synthese stereoselective de l'enantiomere naturel de la girolline a ete realisee a partir du D(-)arabinose : la condensation de cet ose avec l'acetate de formamidine fournit le 4(5)-[1′,2′,3′-trihydroxypropyl]-imidazole ; la chaine laterale est chloree puis aminee via l'azide terminal ; le noyau imidazole est amine ensuite en 2 par diazotation suivie de reduction en presence de rhodium.

Phytochemical investigation of a methanolic extract of the stem of Guatteriopsis friesiana afforded two new 7,7-dimethylaporphine alkaloids, 6,6a-dihydrodemethoxyguadiscine (1) and guatteriopsiscine (3), together with demethoxyguadiscine (2), liriodenine (4), corypalmine (5), and coreximine (6). Their structures were elucidated on the basis of spectroscopic methods (UV, IR, EIMS, HRESIMS, 1D/2D NMR). The absolute configurations of 1 and 3 were determined from the circular dichroism curves. The presence of 7,7-dimethylaporphine alkaloids in this species is important for the chemotaxonomy of Guatteriopsis. Antimicrobial activity of compounds 1-5 was investigated, and 4 showed activity against Rhodococcus equi, with a MIC value of 10 microg x mL(-1).

A series of acetonides was obtained during the formal synthesis of deoxynojirimycin. The 1H NMR spectra of these derivatives contain strongly coupled multiplets covering a chemical shift range of about 1 ppm. The spectra are severely complicated by second-order effects and were assigned by 2D NMR and 13C NMR experiments. Copyright © 1999 John Wiley & Sons, Ltd.

From an ethanolic extract of Peschiera fuchsiaefolia three quaternary alkaloids have been isolated and their structures determined from their spectral data as 12-methoxy-4-methylvoachalotine, 12-methoxy-4-methylvoachalotine ethyl ester and fuchsiaefoline. Analyses of the 13 C NMR spectra of some sarpagine alkaloids were carried out to confirm the structures of these compounds.

Fractionation of an ethereal extract of Peschiera fuchsiaefolia resulted in the isolation of decarbomethoxyvoacamine, demethylvoacamine, voacamidine, perivine, 16-epiaffinine and voacanginehydroxyindolenine, together with the previously reported alkaloids voacamine, voacangine, voachalotine and affinisine. Analysis of the 13 C NMR spectra of the bisindole alkaloids and of 16-epiaffinine is reported.

Orientador : Francisco de Assis Machado Reis Dissertação (mestrado) - Universidade Estadual de Campinas. Instituto de Quimica Mestrado

Orientador : Francisco A. M. Reis Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica Doutorado