Kitol was isolated from unsaponifiable matter of whale liver oil by Tawara and Fukazawa's method(1951) utilizing a difference in the distribution coefficient between n-hexane and 90% methanol, and by further purification on aluminum oxide columns. UV and IR absorption spectra of the isolated kitol were identical with those of pure kitol reported in literatures. In the mass spectrum of perhydrokitol diacetate, the peaks of m/e 478, 449 and 458 were noted as reported by Giannotti et al. (1966a). The presence of these fragments suggests that kitol is composed of two molecules of vitamin A binding between C-11 and C-13'(Fig.4). The splitting out of 55, 68 and 82 from main peaks(m/e 552, 358, 329) also indicates the presence of another bond between C-12 and C-15'. These results suggest that kitol must be of "cyclopentane ring" structure (Fig.1-Ⅳ). The NMR spectrum of kitol showed that kitol possesses five methyl groups(τ8.99) attached to saturated carbons in addition to five methyl groups(τ8.34, 8.20, 8.04) attached to unsaturated ones. Although Omote(1959) has determined the grade of alcohol groups of kitol by Murahashi's method(1936), it was found that kitol (or perhydrokitol) partially decomposes under the condition of the esterification, namely 156℃ for 1 hour. The value for the esterification rate of kitol at 100℃ for 4 hours was found to be median between those of primary and secondary alcohols(Table 3). This result suggests that one of two alcohol groups in kitol is a primary alcohol and the other, a secondary one.
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