109742-46-3Relevant academic research and scientific papers
Non-Enzymatic Oxidation of a Pentagalloylglucose Analogue into Members of the Ellagitannin Family
Ashibe, Seiya,Ikeuchi, Kazutada,Kume, Yuji,Wakamori, Shinnosuke,Ueno, Yuri,Iwashita, Takashi,Yamada, Hidetoshi
supporting information, p. 15402 - 15406 (2017/11/10)
The occurrence of more than 1000 structurally diverse ellagitannins has been hypothesized to begin with the oxidation of penta-O-galloyl-β-d-glucose (β-PGG) for the coupling of the galloyl groups. However, the non-enzymatic behavior of β-PGG in the oxidation is unknown. Disclosed herein is which galloyl groups tended to couple and which axial chirality was predominant in the derived hexahydroxydiphenoyl groups when an analogue of β-PGG was subjected to oxidation. The galloyl groups coupled in the following order: at the 4,6-, 1,6-, 1,2-, 2,3-, and 3,6-positions with respective S-, S-, R-, S-, and R-axial chirality. Among them, the most preferred 4,6-coupling reflected the what was observed for natural ellagitannins. A new finding was that the second best coupling occured at the 1,6-positions. With the detection of a 3,6-coupled product, this work demonstrated that even ellagitannin skeletons with an axial-rich glucose core may be generated non-enzymatically.
Roxbin B is cuspinin: Structural revision and total synthesis
Yamaguchi, Sayuri,Hirokane, Tsukasa,Yoshida, Takashi,Tanaka, Takashi,Hatano, Tsutomu,Ito, Hideyuki,Nonaka, Gen-Ichiro,Yamada, Hidetoshi
, p. 5410 - 5417 (2013/07/26)
Prompted by the outcome that the synthesized roxbin B was not identical to the natural roxbin B, the structural determination process and spectral data were re-examined, with the finding that roxbin B was very likely to be 1-O-galloyl-2,3-(R);4,6-(S)-bis-
Total synthesis of the proposed structure of roxbin B; The nonidentical outcome
Yamaguchi, Sayuri,Ashikaga, Yoshiki,Nishii, Kentaro,Yamada, Hidetoshi
supporting information, p. 5928 - 5931 (2013/02/23)
A proposed structure of roxbin B was synthesized. For the synthesis, a new synthetic method for the preparation of the hexahydroxydiphenoyl (HHDP) bridge was developed that involved the stepwise esterification of axially chiral HHDP acid anhydride. The sy
