72165-31-2

Upstream product

• 735315-15-8 Kaempferol-3-O-(2,3,4-tri-O-acetyl-alpha-L-rhamnopyranoside) 
• 108-24-7 acetic anhydride 
• 482-39-3 kaempferol 3-rhamnoside 

Relevant academic research and scientific papers

Flavonol Glycosides from Jatropha variegata

Five flavonoids were isolated from stems of Jatropha variegata (Forsk.) Vahl, the structures of which were identified as kaempferol 3-O-α-L-rhamnopyranoside, 3-O-α-L-arabinopyranoside, 3-O-β-D-glucopyranoside, 3-O-β-D-galactopyranoside and kaempferol.

Structural basis for the activity of the RSK-specific inhibitor, SL0101

Inappropriate activity of p90 ribosomal S6 kinase (RSK) has been implicated in various human cancers as well as other pathologies. We previously reported the isolation, characterization, and synthesis of the natural product kaempferol 3-O-(3″,4″-di-O-acetyl-α-l-rhamnopyranoside), termed SL0101 [Smith, J. A.; Poteet-Smith, C. E.; Xu, Y.; Errington, T. M.; Hecht, S. M.; Lannigan, D. A. Cancer Res., 2005, 65, 1027-1034: Xu, Y.-M; Smith, J. A.; Lannigan, D. A.; Hecht, S. M. Bioorg. Med. Chem., 2006, 14, 3974-3977: Maloney, D. J.; Hecht, S. M. Org. Lett., 2005, 7, 1097-1099]. SL0101 is a potent and specific inhibitor of RSK; therefore, we performed an analysis of the structural basis for the inhibitory activity of this lead compound. In in vitro kinase assays we found that acylation of the rhamnose moiety and the 4′, 5, and 7-hydroxyl groups are responsible for maintaining a high affinity interaction of RSK with SL0101. It is likely that the hydroxyl groups facilitate RSK binding through their ability to form hydrogen bonds. To determine whether the SL0101 derivatives were specific for inhibition of RSK we analyzed their ability to preferentially inhibit the growth of the human breast cancer line, MCF-7, compared to the normal human breast line, MCF-10A. We have previously validated this differential growth assay as a convenient readout for analyzing the specificity of RSK inhibitors [Smith, J. A.; Maloney, D. J.; Clark, D. E.; Xu, Y.-M.; Hecht, S. M.; Lannigan, D. A. Bioorg. Med. Chem., 2006, 14, 6034-6042]. We found that acylation of the rhamnose moiety was essential for maintaining the selectivity for RSK inhibition in intact cells. Further, the efficacy of SL0101 in intact cells is limited by cellular uptake as well as possible hydrolysis of the acetyl groups on the rhamnose moiety by ubiquitous intracellular esterases. These studies should facilitate the development of a RSK inhibitor, based on the SL0101 pharmacophore, as an anti-cancer chemotherapeutic agent.

Terpenes and lignans from leaves of Chamaecyparis formosensis

84 chemical constituents were isolated from the leaves of Chamaecyparis formosensis. These components include 18 sesquiterpenes, 40 diterpenes, 8 flavones, 7 lignans and 11 miscellaneous compounds. Among them 3 sesquiterpenes, 7 diterpenes and one lignan