40613-68-1Relevant articles and documents
Design, synthesis and biological evaluation of novel l-ascorbic acid-conjugated pentacyclic triterpene derivatives as potential influenza virus entry inhibitors
Wang, Han,Xu, Renyang,Shi, Yongying,Si, Longlong,Jiao, Pingxuan,Fan, Zibo,Han, Xu,Wu, Xingyu,Zhou, Xiaoshu,Yu, Fei,Zhang, Yongmin,Zhang, Liangren,Zhang, Lihe,Zhou, Demin,Xiao, Sulong
supporting information, p. 376 - 388 (2016/02/18)
Since the influenza viruses can rapidly evolve, it is urgently required to develop novel anti-influenza agents possessing a novel mechanism of action. In our previous study, two pentacyclic triterpene derivatives (Q8 and Y3) have been found to have anti-influenza virus entry activities. Keeping the potential synergy of biological activity of pentacyclic triterpenes and l-ascorbic acid in mind, we synthesized a series of novel l-ascorbic acid-conjugated pentacyclic triterpene derivatives (18-26, 29-31, 35-40 and 42-43). Moreover, we evaluated these novel compounds for their anti-influenza activities against A/WSN/33 virus in MDCK cells. Among all evaluated compounds, the 2,3-O,O-dibenzyl-6-deoxy-l-ascorbic acid-betulinic acid conjugate (30) showed the most significant anti-influenza activity with an EC50 of 8.7 μM, and no cytotoxic effects on MDCK cells were observed. Time-of-addition assay indicated that compound 30 acted at an early stage of the influenza life cycle. Further analyses revealed that influenza virus-induced hemagglutination of chicken red blood cells was inhibited by treatment of compound 30, and the interaction between the influenza hemagglutinin (HA) and compound 30 was determined by surface plasmon resonance (SPR) with a dissociation constant of KD = 3.76 μM. Finally, silico docking studies indicated that compound 30 and its derivative 31 were able to occupy the binding pocket of HA for sialic acid receptor. Collectively, these results suggested that l-ascorbic acid-conjugated pentacyclic triterpenes were promising anti-influenza entry inhibitors, and HA protein associated with viral entry was a promising drug target.
Novel 6-O-acylated vitamin C derivatives as hyaluronidase inhibitors with selectivity for bacterial lyases
Spickenreither, Martin,Braun, Stephan,Bernhardt, Guenther,Dove, Stefan,Buschauer, Armin
, p. 5313 - 5316 (2007/10/03)
Previously, we identified ascorbic acid 6-O-hexadecanoate as an up to 1500 times more potent inhibitor of bacterial and bovine hyaluronidases than the parent compound, vitamin C, and determined a crystal structure of hyaluronidase from Streptococcus pneumoniae in complex with the inhibitor. As the alkanoyl chain interacts with a hydrophobic patch of the enzyme we synthesized other 6-O-acylated vitamin C derivatives bearing various lipophilic residues and investigated the inhibition of Streptococcus agalactiae strain 4755 hyaluronidase (SagHyal4755) and of bovine testicular hyaluronidases (BTH) in a turbidimetric assay. All compounds showed selectivity for the bacterial enzyme. Whereas vitamin C 6-O-hexanoate only weakly inhibited SagHyal4755, the inhibition of both enzymes increased with the length of the aliphatic chain. In the case of the 6-O-octadecanoate, IC50 values of 0.9 and 39 μM for SagHyal4755 and BTH, respectively, were determined. Partial replacement of the aliphatic chain with a phenyl, p-phenylene or p-biphenylyl group resulted in inhibitors with activity in the lower micromolar range, too. The title compounds are among the most potent inhibitors of both enzymes known to date.
Simple and Efficient Stereoselective Synthesis of (Z)- and (E)-Alkylidene 2,3-Dimethoxybutenolides from L-Ascorbic Acid and D-Isoascorbic Acid
Khan, M. Akram,Adams, Harry
, p. 687 - 692 (2007/10/02)
Reactions of 2,3-di-O-methyl-5,6-di-O-tosyl-L-ascorbic acid (5b) and 2,3-di-O-methyl-5,6-di-O-tosyl-D-isoascorbic acid (11) with excess of carbon, oxygen and nitrogen nucleophiles produced γ-(Z)-and (E)-alkylidene-2,3-dimethoxybutenolides 6a-e and 12a-d, respectively, in good yields.The formation of the reaction products 6a-e and 12a-d has been rationalised through the involvement of two reaction processes.The ditosylates undergo a stereoselective antiperiplanar E2 reaction first with the nucleophiles to yield exocyclic allylic tosylates of the type 6 or 12 which in a subsequent SN2 reaction give rise to the observed products 6a-e and 12a-d.
FUNCTIONALLY SUBSTITUTED VINYL CARBANIONS VERSATILE INTERMEDIATES IN HETEROCYCLIC SYNTHESIS
Schmidt, Richard R.
, p. 825 - 836 (2007/10/02)
Direct C-lithiation of functionally substituted acrylates yields versatile intermediates for syntheses of butenolides, tetronates, α-hydroxytetronates, pyrrolenines, cyclopentenones, oxalacetates and maleic acid derivatives.A wide variety of substituents are compatible with this lithiation: alkyl, aryl, electron-donating and electron-withdrawing substituents in α- or β-position conducting to interesting regio- and stereoselectivities.The compounds obtained are portions of many natural products.Approaches to the synthesis of aspertetronins, gregatins, ascorbic acids, chlorotricolide, and KDO will be outlined.
Total Synthesis of (R)-Glycerol Acetonide and the Antiepileptic and Hypotensive Drug (-)-γ-Amino-β-hydroxybutyric Acid (GABOB): Use of Vitamin C as a Chiral Starting Material
Jung, Michael E.,Shaw, Teresa J.
, p. 6304 - 6311 (2007/10/02)
Ascorbic acid (Vitamin C) (9) is shown to be a useful, inexpensive chiral starting material for natural products synthesis.It is converted in high yield via two synthetic operations into (R)-glycerol acetonide (7), the more inaccessible enantiomer of glycerol acetonide.Since D-(R)-glyceraldehyde acetonide (4) and the corresponding alcohol 1 have been used in many total syntheses of a wide variety of compounds, the ready availability of the opposite enantiomers L-(S)-glyceraldehyde acetonide (6) and glycerol (7) should be of greate value.As one indication of this potential synthetic utility, the hypotensive, antiepileptic compound (R)-(-)-γ-amino-β-hydroxybutyric acid (GABOB) (8) has been synthesized from ascorbic acid (9) via nine steps in 10percent overall yield.As further evidence of the importance of these synthesis, several useful intermediates for the preparation of the highly active hypotensive agents, the aryloxypropanolamines (5), were prepared from Vitamin C.