friedelane and Neoplasms

Natural pentacyclic triterpenoids (PTs) have been often reported to exhibit a wide range of biological activities. Among them, the anticancer and anti-inflammatory activities are the most studied. Over the last two decades, the number of publications reporting the anticancer effects of PTs has risen exponentially, reflecting the increasing interest in these natural products for the development of new antineoplastic drugs. Among of the most investigated PTs regarding their anticancer properties are oleanane-, ursane and friedelane-types, including oleanolic, glycyrrhetinic, ursolic and asiatic acids, and celastrol, among others. The extensive research in this field shows that the anticancer effects of PTs are mediated by several mechanisms, as they modulate a diverse range of molecular targets and signaling pathways, involved in cancer cell proliferation and survival. Considering the anticancer potential of this class of compounds, a number of semisynthetic derivatives has been synthetized aiming to improve their therapeutic activity and pharmacokinetic properties, and decrease their toxicity. Some of these new semisynthetic derivatives have shown improved anticancer activity in various cancer cell lines and animal models compared with the parent compound. Moreover, some of these compounds have been assessed in clinical trials, proving to be safe for human use. This review updates the most recent findings on the semisynthetic derivatives of oleanane-, ursane- and quinone methide friedelane-type PTs with anticancer activity. A brief introduction concerning the PTs and their anticancer activity is given, and the main semisynthetic modifications that have been performed between 2012 and early 2017 are reviewed and discussed.

Topics: Animals; Antineoplastic Agents; Chemistry Techniques, Synthetic; Humans; Indolequinones; Neoplasms; Oleanolic Acid; Structure-Activity Relationship; Triterpenes

Two new triterpenoids, 30-hydroxylup-20(29)-ene 3β-caffeate (1) and 24-nor-friedelan-6α,10-dihydroxy-1,2-dioxo-4,7-dien-29-oic acid (2), together with eight known compounds 3-10, were isolated from the roots of Celastrus stylosus. The structures of these compounds were elucidated on the basis of spectroscopic analyses. To the best of our knowledge, this represents the first study on the chemical constituents of C. stylosus. The antiproliferative activities of the triterpenoids against six human cancer cell lines (PANC-1, A549, PC-3, HepG2, SGC-7901, and HCCLM3) were evaluated. Compounds 3, 4, and 10 exhibited comparable activities against PC-3 and HCCLM3 cell lines as the positive control taxol.

Topics: Antineoplastic Agents, Phytogenic; Celastrus; Cell Line, Tumor; Cell Proliferation; Humans; Neoplasms; Triterpenes