Harnessing the reactivity of poly(methylhydrosiloxane) for the reduction and cyclization of biomass to high-value products
作者:Nicholas M. Hein、Youngran Seo、Stephen J. Lee、Michel R. Gagné
DOI:10.1039/c9gc00705a
日期:——
Poly(methylhydrosiloxane) (PMHS) has been examined for its ability to reduce and subsequently cyclize carbohydrate substrates using catalytic tris(pentafluorophenyl)borane (BCF). The work herein is the first reported example of the direct conversion of monosaccharides to 1,4-anhydro and 2,5-anhydro products utilizing a hydrosiloxane reducing agent. PMHS is produced from waste products of the silicone
β‐Selective
<i>C</i>
‐Glycosylation and its Application in the Synthesis of Scleropentaside A
作者:G. Jacob Boehlich、Nina Schützenmeister
DOI:10.1002/anie.201900995
日期:2019.4
C‐Glycosides are carbohydrates that bear a C−C bond to an aglycon at the anomeric center. Due to their high stability towards chemical and enzymatic hydrolysis, these compounds are widely used as carbohydrate mimics in drug development. Herein, we report a general and exclusively β‐selective method for the synthesis of a naturally abundant acyl‐C‐glycosidic structural motif first found in the scleropentaside
A practical, facile method was developed for the preparation of 1,5-anhydroalditol via per-O-TMS-glycopyranosyl iodide with LiBH4. A series of 1,5-anhydroalditols were prepared in excellent yields (up to 92%) from unprotected carbohydrates within 2 days under mild conditions. In addition, multi-gram scale preparation of 1,5-anhydroglucitol (1,5-AG), a major polyol present in human serum, was developed
ides, designed as DNA-intercalating agents in structural correlation with antiviral tilorone and anticancer anthracyclines, have been prepared with yields in beta-anomers ranging between 25 and 63%. They have been screened for antiproliferative, immunostimulating and antiviral properties against HSV-1 and HSV-2 viruses. Compounds displaying significant antiviral activity against HSV-2 are acetylated
A newdammarane-type triterpene saponin was isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino. Its structural elucidation was accomplished mainly on the basis of the interpretation of spectroscopic data, such as IR, HR–TOF–MS and NMR. Its cytotoxic activity was evaluated against one human cancer cell line HL-60 using MTT assay.