ABSTRACT Banara parviflora (A. Gray) Benth. is a species that belongs to Salicaceae family and is native to Southern Brazil. Fractionation of the ethanolic extract from Banara parviflora leaves afforded, a new compound identified as N 1,N 8-dibenzoylspermidinyl-N 4-acetamide, a spermidine alkaloid. The structure was elucidated by spectroscopic methods (IR, MS, 1H, 13C and 2-D NMR).

In the last ten years, the interest in natural and semi-synthetic cucurbitacin derivatives has increased, primarily due their cytotoxic and anti-tumoral activities. However, the isolation of glycosylated cucurbitacins has been difficult due the presence of β-glucosidase enzyme. With the aim of obtaining new glycosylated derivatives, the glycosylation of dihydrocucurbitacin B under Köenigs-Knorr and imidate reaction conditions was studied. Novel glycoside derivatives 16-(1,2-orthoacetate-3,4,6-tri-O-acetyl-α-D-glucopyranosyl)-dihydrocucurbitacin B (2), 2-O-β-D-2,3,4,6-tetra-O-acetyl-galactopyranosyl dihydrocucurbitacin B (3) and 2-O-β-D-galactopyranosyl dihydrocucurbitacin B (4) were synthesized for the first time in 17% (2 and 3) and 48% (4) yields.

Das folhas de Lippia alba foram isoladas duas saponinas. As estruturas destas saponinas foram estabelecidas empregando métodos espectroscópicos, principalmente RMN mono e bi-dimensional e espectrometria de massas. Estes novos compostos foram caracterizados como ácido 3-O-β-D-glucopiranosil-28-O-(α-L-rhamnopiranosil-(1?3)-β-D-xilopiranosil-(1?4)-α-L-rhamnopiranosil-(1?2)-α-L-arabinopiranosil)-16α,23-di-hidróxi-olean-12-en-28-óico, designada Lippiasaponina I (2) e como ácido 3-O-β-D-glucopiranosil-28-O-(α-L-rhamnopiranosil-(1?3)-β-D-xilopiranosil-(1?4)-α-L-rhamnopiranosil-(1?3)-α-L-arabinopiranosil)-16α,23-di-hidróxi-olean-12-en-28-óico, designada Lippiasaponina II (3).

Two saponins were isolated from the leaves of Lippia alba. Their structures were established using one- and two-dimensional NMR spectroscopy and mass spectrometry. These new compounds were elucidated as 3-O-β-D-glucopyranosyl-28-O-(α-L-rhamnopyranosyl-(1?3)-β-D-xylopyranosyl-(1?4)-α-L-rhamnopyranosyl-(1?2)-α-L-arabinopyranosyl)-16α,23-dihydroxy-olean-12-en-28-oic acid, named as Lippiasaponin I (2) and as 3-O-β-D-glucopyranosyl-28-O-(α-L-rhamnopyranosyl-(1?3)-β-D-xylopyranosyl-(1?4)-α-L-rhamnopyranosyl-(1?3)-α-L-arabinopyranosyl)-16α,23-dihydroxy-olean-12-en-28-oic acid, named Lippiasaponin II (3).