中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | methyl 3-O-benzyl-4,6-O-benzylidene-2-deoxy-2-C-(2-methoxycarbonylethyl)-α-D-altroside | 131529-42-5 | C25H30O7 | 442.509 |
—— | methyl 3-O-benzyl-4,6-O-benzylidene-2-deoxy-2-C-(prop-2-enyl)-α-D-altropyranoside | 131529-43-6 | C24H28O5 | 396.483 |
—— | methyl 4,6-O-benzylidene-2-deoxy-2-(2-propenyl)-α-D-allohexopyranoside | 126108-10-9 | C17H22O5 | 306.359 |
—— | methyl 2,3-anhydro-4,6-benzylidene-α-D-allopyranoside | 66537-92-6 | C14H16O5 | 264.278 |
Treatment of methyl 2,3-anhydro-4,6-O-benzylidene-α-D-alloside with the anion derived from trimethyl(prop-1-ynyl)silane, allylmagnesium chloride or isobutenylmagnesium chloride introduces a three- or four- carbon substituent at C2 of the sugar. In each case, a hydroboration-oxidation sequence helps convert the centre of unsaturation in the new substituent into a carboxylic acid residue. Subsequent manipulations allow the introduction ofanother carbon at C6 of the sugar to give a highly functionalized precursor to the C1-C9 fragment of tylonolide, the aglycon of the antibiotic tylosin. Attempts at the introduction of an axial methyl group at C4 of the extended sugar also described.