Studies on kitol 1.
Preparation of Kitol from \Vhale liver Oil
Tadashi Tawara and Ryusuke Fukazawa
Willstaedt & Jensenl) and Nakamiya2l pointed out the presence of aVitamin. A-like substance, differing from the ordinary Vitamin A in its
properties, in whale liver oil. Recently, Baxter, et al.3l isolated kitol.
The presence of a foreign substance in whale liver oil had long been
predicted by the difference of. their spectrum analysis and the Carr-Pricereaction from ordinary fish liver oil. The maximum of the absorption
spectrum of the unsaponifiable matter of ordinary fish liver oil is in theneighborhood of 328 mp, but that of whale liver oil is at 290-325 mp, andthe Carr-Price reaction of whale liver oil is blu1sh-purple whereas that offish liver oil colors· blue. From the proximity of the figures of extinctionof 265 mµ and 328 in,u in the absorption spectrum of the.
coefficient,unsaponifiable matter of whale liver oil, it had been believed that theabsorption curves would lie close together and overlap each other and an
apparent maximum would lie in intermediate point.2)

i!·The authors also determined Fig. 1 Unsaponifiable matter of fin whale liver oilE rt
the extinction coefficient E 11.%
cmof the unsaponifiable matter offin. whale liver oil (Fig. 1)* by
the spectrophotometer and wereable to prove this point.
This absorption curve apparently differs from that .of
tunny liver oil (Fig~ 2). The
greatest difference exists in theposition of the absorption maximum and the width of the curve. The Carr-Price reaction of
220 2~0 240 250 260 ~70 280
this unsaponifiable matter of .,.

* The reason that the curve is so wide is because the· absorption is so indistinct that the valueof extinction coefficient, E1 % , does not come out clearly.
1cm

Tadashi Tawara and Ryusuke Fukazawa
Fig. 2 Unsaponifiable matter of tunny liver oil

fin whale liver oil gives bluishpurple color while that of tunny
liver oil, blue.
The oxidation product of
H-+---l---+--+---1-+---'---1---i--+--'-l-+--i600
Vitamin A gives red or reddish
H-+--+--+--+--1--1---'---+--+--+---'-lr--+-15° 0
brown coloring by this reaction.
According to the authors' experiments, majority of this oxidation product transists into saponifiable matter during saponification so that it does notseem to constitute a reason for.__...__.....__,_---'-__,_.1---'---'--'---'-,..-'"''"=-=~100
bluish purple coloration. Naka220 2,0 240 250 260 210 280 290 ,co ,10· 520 ,,a >40 550mµmiya and others harbored adoubt that it might be due to the large amount of cholesterol present but
the authors take the view that this is due to the presence of kitol.
Kitol as isolated by Baxter, et al.,· were colorless, elongated prismatic
crystals of Fp. 88-90°, with a molecular formula corresponding to CoH5s(OH)2, possessing 8 double bonds. It gives an absorption maximum at
290 mµ, and E 1% 290 mµ=707.
1cm
The fact that kitol possessed twice the molecular weight of Vitamin Awas utilized in separating the two by the difference of solubility. The
unsaponifiable matter of fin Fig; 3 Unsaponifiable matter of fin whale liver oil-Fraction Awhale liver oil was dissolved in. petroleum ether and this wasextracted with 90% methanol
into which Vitamin A was transited. The substance which remained in the petroleum ether
solution to the last was examined by the spectrophotometerand the. value of E 1.%. at each.
1cmwave length was shown by acurve (Fig. 3). This substanceshowed an absorption maximum .
2}0 240 250 260 270 280 290
at 290 mµ, and the Carr-Price 220mµ~~__,.-.~----~-~~~__,,._~~c..__,__,__,100)}0)40 )50

Studies on Kitol. I. Preparation of Kitol from Whale liver Oilreaction gives a red coloration.
Apparently, it contained a verysmall amount of Vitamin A.
On the other hand the E 1%
1cmvalue of the substance that tra-87Fig. 4 Unsaponifiable matter of liver oil fin whale-Fraction B

nsite9 to 90% methanol (curvein Fig. 4) gave a maximum
absorption at around 328 mµ, **which is very similar to thecurve of tunny liver oil· (Fig. 2).
It does not give the indistinct
curve as in Fig. 1, any more.
The Carr-Price reaction is blue,
so that this substance must be
nothing but Vitamin A.
From these facts, it can, be assumed that the substance that reamainedin petroleum ether to the last is clearly kitol.
EXPERIMENTAL
250 g. fin whale liver oil was warmed with 500 cc of 20% methanolic
potash for 1 hour in a water bath. After saponification, this was extractedwith ether and the ethereal layer was washed several times with waterand dried with anh~drous Glauber's salt. After distilling off ether, 54 g. of
unsaponifiable matter was obtained. This substance gives bluish purple
coloration by Carr-Price reaction and, according to E 11cm.% curve (Fig. 1) byspctrophotometer* **, ,Possesses an absorption maximum 303 mµ although
the absorption area is so indistinct that it is hard to obtain a correct valueof: E11.l.%.
Accordingly, the curve became one of a wide bartd. This is appa~cm

rently due to the fact that two or more substances are mixed in it andgives a complex absorption so that this must be taken as the apparent
absorption maximum.
The .total amount (54 g) of this unsuponifiable matter was· dissolved in1000 cc. of petroleum ether (Bp. 30-60°), placed in a separating funnel** According to this experiment, the absor13tion maximum of Vitamin A-like substance isolated
from the unsaponifiable matter of tunny liver and whale liver oil is more nearer 325 m11 than328m,11.
*** Spectrophotometer by Carl Zeiss was used. The solvent was absolute alcohol.

'88

Tadashi Tawara and Ryusuke Fukazawaand extracted 38 times with 500 cc each 90% methanol. The petroleum
ether layer was then washed several times with water, dried with anydrous
Glauber's salt and distilled under reduced pressure. A reddish yellow,
syrupy matter was obtained to the amount of 14 g. 90% Metanol solution
was distilled under reduced pressure in carbon dioxide stream and the'residue, composed mostly of water and a small amount of oil drops floating
on it, was placed in a separating funnel. This was extracted with ether
and the ethereal layer was· distilled off after dry in with anhydrous Na2S04.
The residual matter, reddish yellow syrup obtained was ea. 39 g. About
1 g unsuponifiable matter was lost during this separating process.
The substance which transited to 90% methanol (hereafter designatedas fraction B) gives a blue coloration to Carr-Price reaction, extinction
coefficient curve as shown in Fig. 4 which approximately coincides withthat (Fig. 2) of the unsuponifiable matter from tunny liver oil, i. e. itshows an absorption maximum at around 328 mµ and does not give theindistinct absorption as before separation. The Carr-Price reaction is notlonger bluish purple but blue so that this is a substance devoid of foreign
matter, i. e. Vitamin A alone.
The residual matter in petroleum ether "(hereafter designated fractionA) gives a red · coloratin to Carr-Price reaction and extinction coeffcientcurve (Fig. 3) ·is clearly different from that of fraction B (Fig. 4) andpossesf]es an absorption maximum at 290 mµ, Eir~ 290 mµ=500.**** It isapparent that fraction A is kitol.
No presence. of kitol were discovered. in the oil obtained from theeyeball of sperm and sei whales ..
The authors' deepest gratitude is due Dr. Tsutomu Maruyama, Directorof the institute, who gave them kind ·instructions, and to Mr. Tadashi
Nakai of this institute and to Dr. Seiichi Ishikaw~ of the University ofLiterature and Science for their unfailing assistance and advice.
References
1) . H. Willstaedt and H. B. Jensen: Nature, 143, 474 (1939).
2) J. Nakamiya,_ K. Koizumi and I. Kawakami: Riken Iho (Report of the Institute for Physicaland Chemical Research), 20, 576 (1941).
3) F. B. Clough, H. M. Kascher, C. D. Rob_eson and J. G. Baxter: Science, 105, 436 (1947); M.
H. Stern, C. D. Robeson, L. Weisler and J. G. Baxter: J. Am. Chem. Soc., 69, 869 (1947).
4) Embree: J. Am. Chem. Soc., 65, 910 (1943).

**** Extinction coefficient of pure kitol at 290 m,u is 7073) but that of kitol separated by "Embree, etal.4J at first was 580 at 290 mµ, which apparently was still quite impure.
obtained by the author theoretically contains 70% kitol.

Frantion A