Converting maslinic acid into an effective inhibitor of acylcholinesterases
作者:Stefan Schwarz、Anne Loesche、Susana Dias Lucas、Sven Sommerwerk、Immo Serbian、Bianka Siewert、Elke Pianowski、René Csuk
DOI:10.1016/j.ejmech.2015.09.007
日期:2015.10
to act as inhibitors of cholinesterases, up to now maslinic acid has not been part of such studies. For this reason, three series of maslinic acid derivatives possessing modifications at different centers were synthesized and subjected to Ellman's assay to determine their inhibitory strength and type of inhibitory action. While parent compound maslinic acid was no inhibitor in these assays, some of
Abstract Augustic acid, a new oleanane derivative, and a stigmasterol glycoside were isolated from the roots of Ambromaaugusta. Their structures were established as olean-12-en-2β,3β-diol-28-oic acid and stigmast-5,22-dien -3-O-α- d -glucopyranoside respectively, on the basis of full spectral analyses and chemical methods.
2,3-Di-O-acetyl-maslinic acid benzylamide (5) has previously been shown to possess high cytotoxicity for a variety of human tumor cell lines while being of low cytotoxicity to non-malignant cells. Structural modifications performed on 5 revealed that the presence of these acetyl groups in 5 and the presence of (2 beta,3 beta)-configurated centers seems necessary for obtaining high cytotoxicity combined with best selectivity between malignant cells and non-malignant mouse fibroblasts. Compounds carrying an ursane skeleton showed weaker cytotoxicity than their oleanane derived analogs. In addition, the benzylamide function in compound 5 should be replaced by a phenylurea moiety to gain better cytotoxicity while retaining and improving the selectivity. Thus, maslinic acid derived N-[2 beta,3 beta-di-O-acetyl-17 beta-amino-28-norolean-12-en-17-yliphenylurea (45) gave best results showing EC50 = 0.9 mu M (for A2780 ovarian cancer cells) with EC50 > 120 mu M for fibroblasts (NIH 3T3) and triggered apoptosis while caspase-3 was not activated by this compound. (C) 2016 Elsevier Masson SAS. All rights reserved.
Selective killing of cancer cells with triterpenoic acid amides - The substantial role of an aromatic moiety alignment
2,3-Di-O-acetyl-triterpenoic acid derived amides possessing a (2β, 3β) configuration in ring A and two acetyl groups were previously shown to possess high cytotoxicity for human tumor cell lines but to exhibit low cytotoxicity for non-malignant mouse fibroblasts. In this study, augustic acid (1) and 2-epi-corosolic acid (2) were chosen as starting points for the synthesis of analogs. While augustic