Steroidal saponins from the leaves of Cestrum sendtenerianum.

Five steroidal saponins were isolated from the EtOH extract of Cestrium sendtenerianum (Solanaceae), as confirmed by detailed analysis of their 1H, 13C, and two-dimensional NMR spectral data, and by the results of hydrolytic cleavage. The saponins were revealed to contain three hydroxyl groups at the C-1beta, C-2alpha, and C-3beta positions in the spirostanol skeleton, and to bear a di- or triglycoside at C-3 as the common structural features. One of the compounds, a spirostanol triglycoside, showed weak cytotoxic activity on HL-60 human promyelocytic leukemia cells, with an IC50 value of 7.

Cajucarinolide and isocajucarinolide: anti-inflammatory diterpenes from Croton cajucara.

Cajucarinolide and isocajucarinolide, two new clerodane diterpenes, have been isolated from the cortices of Croton cajucara (Euphorbiaceae). These compounds possess anti-inflammatory activity and inhibit bee venom phospholipase A2 in vitro.

Structures and cytotoxic activity relationship of casearins, new clerodane diterpenes from Casearia sylvestris Sw.

Casearins G-R, new cytotoxic clerodane diterpenes have been isolated from the leaves of Casearia sylvestris Sw. (Flacourtiaceae). Their structures have been elucidated by spectroscopic methods and chemical conversions, and their structure-activity relationships have been discussed.

New antitumor principles, casearins A-F, for Casearia sylvestris Sw. (Flacourtiaceae).

New antitumor clerodane diterpenes, named casearins A-F, have been isolated from the leaves of Casearia sylvestris Sw. (Flacourtiaceae). These structures have been completely elucidated by two dimensional nuclear magnetic resonance, circular dichroism spectroscopy, X-ray analysis, and chemical evidences.

A New Indole Alkaloid Glycoside from the Leaves of Palicourea marcgravii.

A new indole alkaloid glucoside, named palicoside, has been isolated from the leaves of PALICOUREA MARCGRAVII (Rubiaceae) collected in Brazil. The structure was established by spectroscopic methods and its chemical conversion to strictosamide.