The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 01, 1993
Filed:
May. 03, 1991
Takashi Ebata, Kanagawa, JP;
Hajime Matsushita, Kanagawa, JP;
Hiroshi Kawakami, Kanagawa, JP;
Koshi Koseki, Kanagawa, JP;
Japan Tobacco Inc., Tokyo, JP;
Abstract
First, levoglucosenone is made to react with methyl lithium in the presence of copper iodide in order to introduce a methyl group into an enone group of levoglucosenone, and to obtain 1,6-anhydro-3,4-dideoxy-4-C-methyl-.beta.-D-erythro-hexopyranose-2-ulose. This methyl compound is oxidized in acetic acid for lactone formation, and (3S,4S)-5-hydroxy-3-methylpentan-4-olide is thus obtained. Further, this lactone is made to react with tosyl chloride in anhydrous pyridine to obtain (3S,4S)-3-methyl-5-tosyloxypentan-4-olide (tosylate). The obtained tosylate is alkylated with n-propyl lithium in the presence of copper iodide to obtain (3S,4R)-3-methyl-4-octanolide. Here, the (3S,4S)-3-methyl-5-tosyloxypentan-4-olide may be treated with potassium carbonate to cleave lactone ring once, thereby obtaining epoxide. After that, the obtained epoxide is alkylated to form lactone ring again to obtain (3S,4R)-3-methyl-4-octanolide.