545-48-2Relevant articles and documents
Biocatalytic allylic hydroxylation of unsaturated triterpenes and steroids by Bacillus megaterium CGMCC 1.1741
Ge, Haixia,Li, Guolong,Shen, Pingping,Wang, Wei,Wang, Weiwei,Xu, Shaohua,Yu, Boyang,Zhang, Jian
, (2020/04/20)
In this study, we described the microbial catalyzed allylic oxidation by Bacillus megaterium CGMCC 1.1741 of three Δ12-pentacyclic triterpenes, erythrodiol (1), uvaol (2), hederagenin (3) and of four steroids including Δ5-steroids, diosgenin (4), pennogenin (5), 25(R,S)-ruscogenin (6) and Δ4-steroid, diosgenone (7). As a result, fourteen metabolites were generated with allyl hydroxyl moiety. Ten (1a-c, 2a, 2c, 3a, 5a-b, and 6a-b) of them were new natural products and their structures were determined on the basis of 1D/2D NMR and HR-MS data. Biocatalytic allylic oxidation by B. megaterium CGMCC 1.1741 is thus a potential non-toxic and efficient alternative method toward metal-mediated oxidation procedures in the synthesis of natural products and medicines.
Synthesis of oleanolic acid analogues and their cytotoxic effects on 3T3 cell line
Tuncay, Salih,Senol, Halil,Guler, Eray Metin,Ocal, Nuket,Secen, Hasan,Kocyigit, Abdurrahim,Topcu, Gulacti
, p. 617 - 625 (2018/08/17)
Background: Oleanolic acid (OA) is a known natural compound with many important biological activities. Thirteen oleanolic acid derivatives linked at C-3 and C-28 were synthesized and their structures were confirmed by1H-and13C NMR and mass spectral analyses. Among them, compounds 4, 6, 8-10, 12, 13 were synthesized for the first time. They were evaluated for their cytotoxic activity. They showed proliferative effect at low concentrations while cytotoxic effect was observed at high concentrations in a dose dependent manner. Methods: We have first synthesized compounds 1 and 2 from the reaction of methyl iodide and OA. Compound 1 was reduced with LiAlH4 to give compound 3, and compound 2 gave compound 9 with MOMBr as a new compound. The compound 10 was then obtained from the reduction of compound 9 with LiAlH4 as a new oleanolic acid derivative. A diol derivative 11 was synthesized from OA and LiAlH4 at the room temperature. Compound 4 was obtained from the reaction of compound 3 with CBr4 as a new analogue of OA, and the reduction of compound 4 afforded compound 5 as a known product. In addition, we synthesized compounds 6-8 from compound 3 using MsCl, MeI and p-nitrobenzoyl chloride, respectively, in good yields. Compounds 6 and 8 are new analogues of OA. The new compounds 12 and 13 were also synthesized starting from OA using with MOMBr and TBDMSiCl as the reagents. The all synthesized compounds were purified by using column chromatography and/or crystallization. Results: In the present study, thirteen OA derivatives linked at C-28 and (or) C-3 were synthesized and evaluated for their cytotoxic activity on 3T3 cell lines which are the standard fibroblast cell lines, derived from Swiss albino mouse embryo tissue. 3T3 cell viability was observed at low concentrations of the tested triterpenoids while they displayed anti-proliferative effect at higher concentrations. Conclusion: Oleanolic acid 28-methyl ester (2) showed fairly different behavior from all the other compounds tested and found to be the least cytotoxic compound. However, at 200 μM concentration, it exhibited the same cytotoxicity with compounds 3, 9 and 10 around 58-59%. Among the tested 13 compounds, 7 exhibited the most drastic decline for the viability from 12,5 μM to 25 μM concentration. Compound 6 displayed the most cytotoxic effect, almost in all concentrations, particularly at 6.25 and 25 μM concentrations while the highest cytotoxic effect at 50 μM was observed for compound 11 among all the tested triterpenoids. As a result, all the tested OA derivatives showed proliferative effect at 1,56 μM although no proliferative effect was observed for OA. Moreover, OA exhibited higher cytotoxic effect than its derivatives, particularly at higher concentrations (50, 100, 200 μM) with an exception for compound 11. Because, the latter showed highest proliferative effect at lowest concentration, and highest anti-proliferative effect at highest concentration which surpassed all the OA derivatives.
Cytotoxic and NF-κB and mitochondrial transmembrane potential inhibitory pentacyclic triterpenoids from Syzygium corticosum and their semi-synthetic derivatives
Ren, Yulin,Anaya-Eugenio, Gerardo D.,Czarnecki, Austin A.,Ninh, Tran Ngoc,Yuan, Chunhua,Chai, Hee-Byung,Soejarto, Djaja D.,Burdette, Joanna E.,de Blanco, Esperanza J. Carcache,Kinghorn, A. Douglas
supporting information, p. 4452 - 4460 (2018/07/31)
Syzygium is a large genus of flowering plants, with several species, including the clove tree, used as important resources in the food and pharmaceutical industries. In our continuing search for anticancer agents from higher plants, a chloroform extract of the leaves and twigs of Syzygium corticosum collected in Vietnam was found to be active toward the HT-29 human colon cancer cell line. Separation of this extract guided by HT-29 cells and nuclear factor-kappa B (NF-κB) inhibition yielded 19 known natural products, including seven triterpenoids, three ellagic acid derivatives, two methylated flavonoids, a cyclohexanone, four megastigmanes, a small lactone, and an aromatic aldehyde. The full stereochemistry of (+)-fouquierol (2) was defined for the first time. Biological investigations showed that (+)-ursolic acid (1) is the major cytotoxic component of S. corticosum, which exhibited also potent activities in the NF-κB and mitochondrial transmembrane potential (MTP) inhibition assays conducted, with IC50 values of 31 nM and 3.5 μM, respectively. Several analogues of (+)-ursolic acid (1) were synthesized, and a preliminary structure-activity relationship (SAR) study indicated that the C-3 hydroxy and C-28 carboxylic acid groups and 19,20-dimethyl substitution are all essential in the mediation of the bioactivities observed for this triterpenoid.
