ABSTRACT
Beta-boswellic acids are considered the main bioactive components of frankincense. Their potential to act as cytotoxic agents, as well as that of their derivatives remained unexploited so far. In this study we were able to prepare derivatives of 11-keto-ß-boswellic acid (KBA) that showed lower IC50 values as determined by a sulphorhodamine B (SRB) assay using several different human tumour cell lines. Monodesmosidic saponins of KBA are as cytotoxic as 3-acetyl-KBA. The presence of a free hydroxyl group at position C-3 seems to lower cytotoxicity while the presence of an amide function at C-24 improves cytotoxicity. The most active compound of this series gave IC50 values as low as 4.5 µM. Cell death proceeded mainly via apoptosis.
Subject(s)
Amides/pharmacology , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Breast Neoplasms/pathology , Saponins/pharmacology , Triterpenes/pharmacology , Uterine Cervical Neoplasms/pathology , Amides/chemical synthesis , Amides/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Breast Neoplasms/drug therapy , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Female , Humans , Molecular Structure , Saponins/chemical synthesis , Saponins/chemistry , Structure-Activity Relationship , Triterpenes/chemistry , Uterine Cervical Neoplasms/drug therapyABSTRACT
A series of triterpene endoperoxides was synthesized and screened for antitumor activity in a panel of 15 human cancer cell lines by a sulforhodamine-B (SRB) assay. The compounds induce apoptosis and show excellent antitumor activity.
Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Peroxides/pharmacology , Triterpenes/pharmacology , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Cell Survival/drug effects , Dose-Response Relationship, Drug , Humans , Inhibitory Concentration 50 , Molecular Structure , Peroxides/chemical synthesis , Structure-Activity Relationship , Triterpenes/chemical synthesisABSTRACT
Defensive secretions of adult and larval Suocerathrips linguis (Phlaeothripidae, Thysanoptera) were found to contain a long-chained acetate, (11Z)-11,19-eicosadienyl acetate, that was not previously known to occur naturally. This substance occurred together with octadecyl acetate and other long-chained acetates. The eicosadienyl acetate repels ants and spreads on the surface of such potential predators. The mixture can provide a long-lasting surface coating.
