Synthesis of Okicamelliaside, a Glucoside of Ellagic Acid with Potent Anti-Degranulation Activity

Abstract

Okicamelliaside, a glucoside of ellagic acid with potent anti-degranulation activity, was synthesized from ellagic acid. The regioselectivity, solubility, and high reactivity of the intermediates throughout the synthesis were obtained by the complementary use of triisopropylsilyl (TIPS) and methoxyethoxymethyl (MEM) protective groups on the aglycone skeleton.

Synthetic Ellagic Acid Glycosides Inhibit Early Stage Adhesion of Streptococcus agalactiae Biofilms as Observed by Scanning Electron Microscopy

“…Critically important, this compound is soluble in organic solvents conventional for glycosylation chemistry. To generate the EA glycosyl acceptor, TBAF‐mediated desymmetrization gave the C‐3 phenol 8 in 85–90 % yield . This has been previously confirmed to occur at the C‐3 position selectively, likely due to inductive effects of the endocyclic lactone.…”

Computational studies on searching potential phytochemicals against DNA polymerase activity of the monkeypox virus

“… 4 Ellagic acid glucoside −9.8 Potent anti-degranulation activity. 55 Site 1: Conventional hydrogen bond: SER333, PHE494, LYS337, TYR496, ALA498, SER305, GLN304, MET313, Unfavorable bond: GLY312, Van der Waal: GLN336, ARG302, HIS319, VAL493, ILE501, ARG497, SER306, ASN303, ASN315, HIS307, CYS311. 5 6-Hydroxyluteolin 7-O-rhamnoside −9.7 antioxidant and anti-inflammatory agent.…”

Identification of Ellagic Acid Rhamnoside as a Bioactive Component of a Complex Botanical Extract with Anti-biofilm Activity

“…To control the regioselectivity of the glycosylation, EA was first protected as the per- O - t -butyldimethylsilyl ether (per- O -TBS ether) 16 ( Figure 2 ) (Kobayashi et al, 2013). A previously published X-ray crystal structure indicates that tetrabutylammonium fluoride (TBAF)-mediated deprotection of a per- O -silyl EA derivative occurs preferentially at the 3- and 3′-silyl ethers to afford the 3,3′-diphenolate in situ , presumably due to inductive effects of the proximal endocyclic lactone oxygen (Kobayashi et al, 2013). …”

“…The compound was synthesized in analogy to a published procedure with some modifications (Kobayashi et al, 2013). EA (2 g, 6.62 mmol), 4-(dimethylamino)pyridine (DMAP) (18.5 mg, 0.199 mmol), and imidazole (2.25 g, 33.1 mmol) were suspended in CH 2 Cl 2 /dimethylformamide (DMF) (30 mL/10 mL).…”