ABSTRACT
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 7.7 microg/ml.
Subject(s)
Saponins/isolation & purification , Solanaceae/chemistry , Steroids/chemistry , Carbohydrate Conformation , Carbohydrate Sequence , Plant Leaves/chemistry , Saponins/chemistry , Spectrum AnalysisABSTRACT
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.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Diterpenes/pharmacology , Plants/chemistry , Spiro Compounds/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/isolation & purification , Diterpenes/chemistry , Diterpenes/isolation & purification , Mice , Molecular Structure , Phospholipases A/antagonists & inhibitors , Phospholipases A2 , Spiro Compounds/chemistry , Spiro Compounds/isolation & purificationABSTRACT
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.
Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Diterpenes/chemistry , Plants, Medicinal/analysis , Animals , Cell Line , Diterpenes/pharmacology , Structure-Activity RelationshipABSTRACT
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.
Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Diterpenes/isolation & purification , Plants, Medicinal/analysis , Animals , Cricetinae , Diterpenes/pharmacology , Male , Mice , Mice, Inbred ICR , Sarcoma 180/drug therapy , Tumor Cells, Cultured/drug effectsABSTRACT
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.
Subject(s)
Diterpenes/toxicity , Plants, Medicinal/analysis , Animals , Brazil , Cell Survival/drug effects , Cells, Cultured , CricetinaeABSTRACT
Ellipticine (EPC), a natural alkaloid extracted from Aspidosperma williansii (Apocynaceae), is known to have antitumor and cytotoxic activities on various types of tumors. This drug showed a strong clastogenic effect on bone marrow cells of Wistar rats treated in vivo (7.75-31.00 mg/kg body weight). EPC was also tested in vitro using the human peripheral blood lymphocyte system, at concentrations 100 times lower than those used in the in vivo test on rats, since the cytotoxic effect on lymphocytes was very strong. At the 2 highest concentrations used (7.75 X 10(-1) and 1.55 X 10(-1) micrograms/ml culture medium), EPC induced a statistically significant increase in the frequency of chromosome aberrations and sister-chromatid exchanges in lymphocytes. Based on data reported in the literature, we have tried to establish relationships between the clastogenic effect observed and the process of EPC intercalation into DNA and the formation of protein-associated DNA-strand breaks probably promoted by topoisomerase enzymes.
