One of two alcohol groups of kitol was oxidized by Oppenauer oxidation. A study of a carbonyl group of this oxidized kitol (F-Ⅰ) has been made by NMR spectrum (Fig.11). It was found that the carbonyl group is ketonic one indicating the presence of secondary alcohol group in kitol. The IR and NMR spectra of the oxidized kitol suggest that this ketone group is located in a five-membered ring, and that there exists an active methylene adjacent to the ketone group (Fig.11). It was also demonstrated that the oxidized kitol is almost quantitatively reduced to kitol with LiAlH_4.