| 摘要 |
<p>PURPOSE:To obtain the titled substance which is an important compound having the antimicrobial activity industrially and advantageously, by alkylating a lactone containing an optical isomer or a racemate as a raw material, and removing the protecting group of the hydroxyl group. CONSTITUTION:A lactone of formula I (R<1> is alkyl; X is a protecting group of the hydroxyl group) is reacted with a strong base, e.g. lithium amide, to form an anion at the alpha-position to the carbonyl group. The resultant compound is then alkylated with an alkylating agent, e.g. methyl bromide, and the protecting group of the hydroxyl group is then removed to afford a compound of formula II (R<2> is alkyl). The compound of formula I is obtained by reducing a 2-hydroxy-2-alkyl-6-heptenal readily preparable from an aminal of 6-hepten-2-on-1-al as a raw material compound, protecting primary hydroxyl group of the resultant 2-alkyl-6-heptene-1-,2-diol, and cleaving the double bond of the resultant compound oxidatively.</p> |
