24198-97-8Relevant articles and documents
Total Synthesis of the Natural Products Ulmoside A and (2 R,3 R)-Taxifolin-6- C -β- d -glucopyranoside
Batchu, Venkateswara Rao,Dorigundla, Aravind Reddy,Gurrapu, Raju,Macha, Lingamurthy,Vanka, Umamaheswara Sarma
, p. 1097 - 1101 (2020/07/03)
An efficient first total synthesis of highly polar ulmoside A and (2 R,3 R)-taxifolin-6- C -β- d -glucopyranoside, useful for the prevention of metabolic disorders, has been described. Key elements of the synthesis include a Sc(OTf) 3-catalyzed regio- and stereoselective C -glycosidation on taxifolin in 35percent yield with d -glucose and chiral semipreparative reverse-phase high-performance liquid chromatography (HPLC) for the separation of both taxifolins and the diastereomeric mixture of taxifolin-6- C -β- d -glucopyranosides. Correlation of the analytical data of synthetic ulmoside A and its diastereomer with a natural ulmoside A sample confirmed the assigned absolute stereochemistry of the natural products.
Stereospecific inhibition of nitric oxide production in macrophage cells by flavanonols: Synthesis and the structure-activity relationship
Jiang, Wen-Jun,Ishiuchi, Kan'Ichiro,Furukawa, Megumi,Takamiya, Tomoko,Kitanaka, Susumu,Iijima, Hiroshi
, p. 6922 - 6929 (2015/11/11)
To explore the structure-activity relationships on the inhibitory activity of flavanonols against nitric oxide (NO) production in inflammatory cells, we synthesized 19 flavanonols which shared a common 3,5,7-trihydroxychroman scaffold. A range of substitutions was included in the B ring in order to investigate the structure-activity relationship. We also succeeded in isolating stereoisomers from 16 of the flavanonols using chiral column chromatography. The inhibitory effects of these compounds on NO production were examined in RAW 264.7 cells (a murine macrophage-like cell line), which were activated by lipopolysaccharide (LPS). We only observed inhibitory activity against NO production in (2R,3R) stereoisomers, while the inhibitory activities of (2S,3S) stereoisomers were significantly weaker. We also evaluated the free radical scavenging potential of the flavanonols using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Each stereoisomer indicated the equivalent DPPH scavenging potential as expected. The radical scavenging activity was not correlated with the inhibitory activity against NO. The inhibition of NO production by flavanonols is stereospecific and cannot simply be explained by their radical scavenging activity. We propose the possible existence of a 'target' molecule for flavanonols which is involved in the production and/or regulation of NO in RAW 264.7 cells.
Design, synthesis, and examination of neuron protective properties of alkenylated and amidated dehydro-silybin derivatives
Yang, Lei Xiang,Huang, Ke Xin,Li, Hai Bo,Gong, Jing Xu,Wang, Feng,Feng, Yu Bing,Tao, Qiao Feng,Wu, Yi Hang,Li, Xiao Kun,Wu, Xiu Mei,Zeng, Su,Spencer, Shawn,Zhao, Yu,Qu, Jia
supporting information; experimental part, p. 7732 - 7752 (2010/08/06)
A series of C7-O- and C20-O-amidated 2,3-dehydrosilybin (DHS) derivatives ((±)-1a-f and (±)-2), as well as a set of alkenylated DHS analogues ((±)-4a-f), were designed and de novo synthesized. A diesteric derivative ofDHS((±)-3) and two C23 esterifiedDHSanalogues ((±)-5a and (±)-5b) were also prepared for comparison. The cell viability of PC12 cells, Fe2+ helation, lipid peroxidation (LPO), free radical scavenging, and xanthine oxidase inhibition models were utilized to evaluate their antioxidative and neuron protective properties. The study revealed that the diether atC7-OHand C20-OHas well as the monoether at C7-OH, which possess aliphatic substituted acetamides, demonstrated more potent LPO inhibition and Fe2+chelation compared to DHS and quercetin. Conversely, the diallyl ether at C7-OH and C20-OH was more potent in protection of PC12 cells against H2O2-induced injury than DHS and quercetin. Overall, the more lipophilic alkenylated DHS analogues were better performing neuroprotective agents than the acetamidated derivatives. The results in this study would be beneficial for optimizing the therapeutic potential of lignoflavonoids, especially in neurodegenerative disorders such as Alzheimer's and Parkinson's disease.
