A short access to the macrocyclic core of cycloviracin and glucolipsin

Macrolactonizations in the Total Synthesis of Natural Products

“…DMC ( 30 ) has found application in the selective dimerization of seco-acids in the synthesis of cyclic glycolipids such as cycloviracins, fattivaricins, glucolipsins, and macroviracins. − The use of an added metal cation (potassium − or sodium 471 ) is crucial for the selectivity, and in this case the macrodilactonization is believed to proceed in a template-directed manner (Scheme ).

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Secondary decomposition of levoglucosan in pyrolytic production from cellulosic biomass

“…Notably, the rigid conformation and the sterically hindered b-D-face of the molecule are advantageous for regioselective protection of the OH groups [2] and stereoselective functionalization [3]. Preparation of various biologically active compounds such as antibiotic macrolides [4][5][6][7][8] has been approached starting from levoglucosan [4][5][6][7][8][9][10][11]. Saccharification through rapid or vacuum pyrolysis of cellulosic biomass has also been proposed as a pretreatment method for ethanol fermentation [12][13][14].…”

Making natural products from renewable feedstocks: back to the roots?

“…Macrolide precursor for glucolipsin synthesis. In 2003, Cleophax and coworkers utilized cellulose-derived 114 and dimethyl malate for the synthesis of the macrocyclic moiety 393 542 which could be converted into the antibiotic glucolipsins (394a-b, Scheme 62) 543 and cycloviracins (not shown). [544][545][546][547] Although a number of total and formal syntheses which also use bio-based starting materials in the form of e.g.…”