Synthesis, biological evaluation and structure-activity relationship studies of hederacolchiside E and its derivatives as potential anti-Alzheimer agents

Biological and Pharmacological Effects of Synthetic Saponins

“…Oleanane-, ursane-, furostane-saponins were able to inhibit α-glucosidase with IC 50 = 9.2, 448, 96 µM, respectively, and the positive control, acarbose, was found to inhibit α-glucosidase in the 500-1000 µM range [41,51,69]. Cytoprotective effects were found in oleanane-saponins for the protection of neuron cells from H 2 O 2 -and Aβ 1-42 -induced injury [38]; dammarane-saponins for the protection of HaCaT cells from sunlight by increased sun protection factor (SPF) rating [61] and prevention of 2, 2 -azobis(2-methylpropionamidine) dihydrochloride (AAPH)-induced hemolysis in rabbit erythrocytes [59].…”

“…Synthetic oleanolic saponins (Figure 2) have been evaluated on their antitumor [14,18,21,[29][30][31][32][33][34][35][36][37], anti-Alzheimer [38], antiviral [39,40], antiglucosidase [41], immunomodulating [42], and detoxification [43] activities (Table 1). Yang and co-workers reported a series of structures derivatized from potent antitumor Pulsatilla saponins, hederacolchiside A and D, elucidating the selectivity between the antitumor activity and hemolytic toxicity of compounds.…”

“…Evaluation of the neuroprotective effect of hederacolchiside E derivatives bearing various sugar chains was performed by Cheng and co-workers; compound 10 was found to prevent cell death by reducing the release of lactate dehydrogenase, level of intracellular ROS, and malondialdehyde resulting from Aβ 1-42 treatment in PC12 cells [38]. Song and co-workers generated a series of 3-O-β-chacotriosyl oleanolic saponins serving as entry inhibitors of H5N1, revealing that a disubstituted amide modification at 28-COOH (11), alteration of C-3 configuration from β to α (12), and introduction of an oxo group to C-11 of oleanolic acid (13) can enhance the selectivity index between antiviral and toxicity [39,40].…”

“…Applying oxyamine neoglycosylation to construct a series of 6-deoxy and 2,6-dideoxy-d-glucose derivatives of digoxin revealed that the induction of Nur77 protein expression was strong in some compounds but lacked sufficient cytotoxicity against cancer cells [135]. To further improve the cytotoxicity against NIH-H460 cancer cells, digoxigenin derivatives containing different carbohydrates at 3-OH were synthesized, and the O-linked saponins bearing D -ribose and L -rhamnose (38,39) exhibited nanomolar range cytotoxicity which was better than digoxin. However, the inductions of the Nur77 protein only showed a low correlation to cytotoxic effects [70].…”

Antioxidant effects of bioactive compounds isolated from cordyceps and their protective effects against UVB‐irradiated HaCaT cells

“…Therefore, it is of particularly importance to develop high‐efficiency antioxidant ingredients in cosmetics industry. Man‐made antioxidants often have certain toxic and side effects, which make their application under strict control compared with natural substances . Cordyceps, the complex of a fungal fruiting body on a caterpillar body, is a rare and expensive Chinese medicine.…”