- Syntheses of glycyrrhetic acid α-diglycosides and enol α-glycosides
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Glycyrrhetinate α-monoglycoside derivatives 8, 10 and 12, all having a trichloroacetyl group at the C-2 position of the pyranose ring, were treated with NH3-saturated ether at 0°C to give the corresponding alcohols 13, 15 and 17, accompanied by 2'-chloroderivatives, 14, 16 and 18, respectively. Glycosylations of the alcohols 13, 15 and 17 with methyl 2,3,4-tri-O-acetyl- α-D-glucuronatopyranosyl bromide 19 in the presence of AgOTf in dry CH2Cl2 gave the corresponding α-diglycosides 20, 22 and 24 together with the enol α-glycosides 21, 23 and 25, respectively. Glycosylations of the diglycoside derivatives 20, 22 and 35 having no reactive OH group in the molecules with 19 for longer reaction times gave quantitatively the enol α-glycoside derivatives 21, 23 and 36, respectively. Glycosylation of the monoglycoside derivative 37, which has a poorly reactive OH group at the C-4 position on the pyranose ring, with 19 gave an enol α-glycoside 38. The mechanism of the formation of enol α-glycosides was investigated. Removal of the protecting groups of 20, 22 and 24 by successive treatment with 1.5N NaOMe in MeOH and 5% KOH in EtOH-H2O (1:1) gave the free α-diglycosides 26-28, and removal of those of 31, 21, 23, 25 and 36 by treatment with 5% KOH in EtOH-H2O (1:1) under reflux gave the free enol α-glycosides 41-45, respectively.
- Saito,Sumita,Kanda,Sasaki
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- A method for the preparation of trans-glycyrrhizic acid
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The invention takes the market glycyrrhizinate binds the raw material, the acid out-in and get the glycyrrhizic acid, glycyrrhetic acid according to the cis and trans glycyrrhizic acid in different solubility in a solvent, acetone or butanone recrystallization, cis glycyrrhizic acid remaining in the mother liquor, trans glycyrrhizic acid in the solvent precipitation, filtration can make the high purity of trans-glycyrrhizic acid, the invention solves the glycyrrhizic acid stereoisomers not easy to separate the key technical, with technological repeatability, the operation is simple, environmental protection, and the product obtained by the characteristic of high purity, is suitable for industrial production.
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Paragraph 0018; 0021; 0024
(2019/07/04)
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- METHOD FOR PRODUCING GLYCYRRHIZINIC ACID AND GALACTURO GLYCYRRHIZINIC ACID, AND INTERMEDIATE USED FOR THE PRODUCTION METHOD
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PROBLEM TO BE SOLVED: To provide a synthesis method that makes it possible to produce high-purity glycyrrhizinic acid or galacturo glycyrrhizinic acid, simply and in high yields. SOLUTION: A production method includes performing glycosylation of position-3 hydroxy group of glycyrrhetinic acid, then performing selective galactosylation or glycosylation at position-2', and through deprotection, performing selective oxidation of a primary hydroxy group. SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
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Paragraph 0039; 0045
(2018/07/28)
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- Methyl isoglycyrrhizinate refining method
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According to the present invention, a methyl isoglycyrrhizinate crude product is used as a raw material and is refined to obtain the methyl isoglycyrrhizinate fine product, wherein the impurity A content can be controlled at less than 0.3%, and the single impurity content in the magnesium isoglycyrrhizinate can be controlled at less than 0.1%; and the preparation method has advantages of simpleness, good process reproducibility, simple operation, high yield and high product purity, and is suitable for industrial large-scale production.
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Paragraph 0016
(2018/04/02)
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- Acyclovir transdermal delivery system
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A transdermal formulation for providing antiviral effect in dermis or epidermis, wherein comprising (a) 0.01 to 30 weight percent of antiviral drug; (b) 0.05 to 20 weight percent of a Chinese medicine enhancer; and (c) a pharmaceutical acceptable vehicles. The antiviral drug is selected from the group consisting of ACV(Acyclovir), Carbovir, DDA(2',3'-Dideoxyadnosine), HPMPA(1-(3-Hydroxy-2-phosphonylmethoxylpropyl)-adenosine), DHPG(Ganciclovir), Desciclovir, IDC (5-Iodo-2'-deoxy-cytidine), Vidarabine(Ara-A), DDI(2',3'-Dideoxyinosine), Cordycepin, Cytarabine, Deoxyguanosine, d4T(2',3'-Didehydro-3'-deoxythymidine), FIAC(2'-Fluoro-5-iodoaracytosine), AZT(ZDV, Zidovudine), Ara-T(1- beta -D-Ara-binofuranosylthymine), Deoxythymidine, Ribavirin, EDU(5-Ethyl-2'-deoxy-uridine), Enviroxime, Amantadine, Arildone, HPMPC(9-(3-Hydroxy-2-phosphonyl-methoxyl-propyl)cytidine), Riboxamide, Rimantidine, Tromantadine, Foscamet sodium, Moroxydine, F3T(5-Trifluoro-methyl-2'-deoxy-uridine), BVDU (Bromovinyldeoxyuridine). Preferably, the Chinese medicine enhancer is oleanolic acid, and the pharmaceutical acceptable vehicles is polyethylene glycols.
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- Transdermal preparations of oxicams
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The present invention is related to a transdermal preparation of oxicams. The preparation comprises 0.1% to 50% of an oxicam, 0.1% to 70% of pure compositions from Chinese herbal enhancers as enhancers, as well as other necessary excipients for transdermal delivery of an active ingredient. This transdermal preparation is intended to be used for anti-inflammatory cases, but with few gastrointestinal side effects.
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- TRANSFORMATIONS OF GLYCYRRHIZIC ACID. III.* SYNTHESIS OF NEW GLYCOPEPTIDES CONTAINING METHYL ESTERS OF AMINO ACIDS
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A new selective method has been proposed for the preparation of glycopeptides of β-glycyrrhizic acid (I) containing fragments of methyl esters of amino acids by reacting tris-N-hydroxysuccinimidic ester of a glycoside, obtained in situ using N,N'-dicyclohexylcarbodiimide, with hydrochlorides of methyl esters of amino acids or dipeptides in the presence of triethylamine.
- Baltina, L. A.,Tolstikov, G. A.
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p. 1115 - 1120
(2007/10/02)
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- Compositions containing glycyrrhizin
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There are provided compositions for the prevention and for the treatment of oral diseases based on glycyrrhizin, and a drug, and for the treatment of oral, nasal and genital lesions due to Herpes simplex, based on glycyrrhizin in combination with an antiviral agent such as idoxuridine.
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