GLUCOSIDES OF THE PHOSPHOLIPINS 117 



In the tissues of the liver we find considerable quantities of a water- 

 soluble phospholipin, Jecorin, which yields glucose, fatty acids, glycero- 

 phosphoric acid, choline and hydrogen sulphide on hydrolysis by alka- 

 lies. Early observers were inclined to regard jecorin simply as lecithin 

 glucoside, but the sulphur-content of jecorin precludes the adoption 

 of this simple interpretation. Jecorin, like other phospholipins, is 

 exceedingly hygroscopic and susceptible to oxidation. It is soluble 

 in alcohol containing w^ater and in ether, but is insoluble or but spar- 

 ingly soluble in absolute alcohol. With silver nitrate an aqueous 

 solution of jecorin yields a precipitate which dissolves in excess of the 

 jecorin solution; on the addition of ammonia this mixture turns dark 

 red. It appears highly probable from the variability of the analytical 

 data obtained with jecorins from different sources that a variety of 

 substances of this general type exist in the tissues; more especially 

 is this indicated by the variable ratio of phosphorus to nitrogen which 

 in some preparations approximates to the value P : N = 1 : 2, while 

 in others P : N = 1 : 4. In any case it is probable that the phospho- 

 lipin portion of the molecule is not simply lecithin. All preparations 

 contain sodium, which appears to be present in chemical combination. 



In the anterior lobe of the pituitary gland is found another water- 

 soluble phospholipin which, however, instead of yielding glucose on 

 hydrolysis, yields the cyclose Inosite. This substance, Tethelin, is 

 soluble in water, alcohol or ether, but is insoluble in a mixture of 

 Alcohol and ether in the proportion of one part by volume of alcohol 

 to one and one-half parts by volume of ether. It contains phosphorus 

 and nitrogen in the proportion of 1 : 4 and one-half of the nitrogen 

 is present in the molecule in the form of amino-groups. On hydrolysis 

 the yield of amino-nitrogen increases to three -fourths of the total 

 nitrogen, indicating, probably, that one of the nitrogen atoms is 

 present in the form of an imino-group (= NH). 



Tethelin is exceedingly hygroscopic and susceptible to oxidation 

 which is accelerated by traces of moisture. Oxidation is accompanied 

 by progressive darkening of the originally cream-colored powder, so 

 that it ultimately becomes dark brown or almost black; at the same 

 time the iodine absorption number decreases. With a 2 per cent, 

 solution of p-dimethylamino-benzaldehyde in hydrochloric acid cf 

 sp. gr. 1.09, aqueous solutions of tethelin yield a pink coloration 

 (Ehrlich's Reaction, indicating an acetylated oxyamino-acid radical). 

 The nitrogenous base has not as yet been identified, but it probably 

 contains an Iminazolyl radical: 



This is of great significance in view of the fact that the active prin- 

 ciple of the Posterior Lobe of the Pituitary Body is also an iminazolyl 

 derivative and the possibility is indicated, 'which the anatomical 



