trichorabdal-type, of diterpenoidsfromRabdosiatrichocarpa, the latter showed the highest antitumor activity against Ehrlich ascites carcinoma in mice. Their potent activities were attributed to synergistic increase arising from the presence of two active sites in one molecule. In vitro activity against HeLa cells and in vivo activity against P 388 lymphocytic leukemia of diterpenoids and related compounds
Motivated by our interest in hydrogen sulfide bio-chemistry and ent-kaurane diterpenoid chemistry, 14 hydrogen sulfide donating derivatives (9, 11a-c, 12a-c, 13, 14, 16a-c and 17a-b) of ent-kaurane and spirolactone-type 6,7-seco-ent-kaurane were designed and synthesized. Four human cancer cell lines (K562, Bel-7402, SGC-7901 and A549) and two normal cell lines (L-02 and PBMC) were selected for antiproliferative assay. Most derivatives showed more potent activities than the lead ent-kaurane oridonin. Among them, compound 12b exhibited the most potent antiproliferative activities, with 1050 values of 1.01, 0.88, 4.36 and 5.21 mu M against above human cancer cell lines, respectively. Further apoptosis-related mechanism study indicated that 12b could arrest Bel-7402 cell cycle at G1 phase and induce apoptosis through mitochondria related pathway. Through Western blot assay,12b was shown to influence the intrinsic pathway by increasing the expression of Bax, cleaved caspase-3, cytochrome c and cleaved PARP, meanwhile suppressing procaspase-3, Bcl-2, Bcl-xL and PARP. (C) 2019 Elsevier Masson SAS. All rights reserved.
Synthesis of spirolactone-type diterpenoid derivatives from kaurene-type oridonin with improved antiproliferative effects and their apoptosis-inducing activity in human hepatoma Bel-7402 cells
A series of novel spirolactone-type diterpenoid derivatives of oridonin (12a-j) were designed and synthesized. All the target compounds showed improved anti-proliferative activity against a panel of human cancer cell lines and the most effective compound 12j was more potent than positive control Taxol in 1062 and Bel-7402 cells with IC50 values of 0.39 mu M and 1.39 mu M, respectively. The cellular mechanisms showed that compound 12j induced apoptosis at low micromolar concentrations in human hepatoma Bel-7402 cells. These results demonstrate that the spirolactone-type diterpenoid derivatives of oridonin have optimized growth inhibitory activity against cancer cells and interesting apoptosis-inducing ability. (C) 2012 Elsevier Masson SAS. All rights reserved.