PDF/A is an ISO-standardized version of the Portable Document Format (PDF) specialized for the digital preservation of electronic documents. The extension in the file name is pdf. PDF/A differs from "normal" PDF in that features ill-suited for long-term archiving are omitted. PDF/A embeds all fonts used in the document within the PDF file, so that the user of your file will not have to have the same fonts that you used to create the file installed on their computer in order to read it. Recommended versions are PDF/A-1a, -1b, -2a or -2b.PDF/A conversion -how to convert files to the PDF/A -format using different tools Microsoft Word (Office) and PDF-Xchange pro/Editor are installed on all Windows workstations managed by Aalto IT.
Plant‐derived carbohydrates are an abundant renewable resource. Transformation of carbohydrates into new products, including amine‐functionalized building blocks for biomaterials applications, can lower reliance on fossil resources. Herein, biocatalytic production routes to amino carbohydrates, including oligosaccharides, are demonstrated. In each case, two‐step biocatalysis was performed to functionalize d‐galactose‐containing carbohydrates by employing the galactose oxidase from Fusarium graminearum or a pyranose dehydrogenase from Agaricus bisporus followed by the ω‐transaminase from Chromobacterium violaceum (Cvi‐ω‐TA). Formation of 6‐amino‐6‐deoxy‐d‐galactose, 2‐amino‐2‐deoxy‐d‐galactose, and 2‐amino‐2‐deoxy‐6‐aldo‐d‐galactose was confirmed by mass spectrometry. The activity of Cvi‐ω‐TA was highest towards 6‐aldo‐d‐galactose, for which the highest yield of 6‐amino‐6‐deoxy‐d‐galactose (67 %) was achieved in reactions permitting simultaneous oxidation of d‐galactose and transamination of the resulting 6‐aldo‐d‐galactose.
Chloroperoxidase from Caldariomyces fumago catalyzes the selective oxidation of furfuryl alcohols in an Achmatowicz‐type ring expansion. In combination with glucose oxidase as oxygen‐activating biocatalyst, a purely enzymatic, aerobic protocol for the synthesis of 6‐hydroxypyranone building blocks is obtained. Thanks to an only modest stereochemical bias of the oxygenating heme protein, optically active alcohols of either configuration are converted without a significant mismatch opening up opportunities for enantioselective multienzymatic cascades. Balancing the oxidase‐driven aerobic activation, extended enzyme half‐lives and productive conversion of poorly soluble and slowly reacting substrates can be achieved with high yields of the six‐membered O‐heterocycles.
Starting from biogenic furfurals, an operationally simple and scalable condensation-umpolung-alkylation protocol was employed in the synthesis of racemic furfurylamines. Subsequent enzymatic kinetic resolution by ω-transaminase or lipase biocatalysts allows for the preparation of functionalized heterocyclic building blocks from biogenic base chemicals in optically pure form.
Lipase B from Candida antarctica catalyzes the oxidative ring expansion of furfuryl alcohols using aqueous hydrogen peroxide to yield functionalized pyranones under mild conditions. The method further allows for the preparation of corresponding piperidinone derivatives by enzymatic rearrangement of N-protected furfurylamines.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.