376 Report of the Department of Chemistry of the 



bluish-white amorphous precipitate was produced, which dissolved 

 completely on cooling. 



The aqueous solution of the substance was therefore treated with 

 lead acetate in excess. The resulting precipitate was filtered, washed, 

 and decomposed with hydrogen sulphide. These operations were 

 repeated several times until a perfectly white lead precipitate was 

 obtained. This was finally decomposed with hydrogen sulphide and 

 the solution concentrated in vacuum until a thick, practically color- 

 less syrup remained. On scratching with a glass rod this immediately 

 crystallized to a white solid mass. The substance was recrystallized 

 from water with addition of alcohol. It was then obtained in 

 beautiful colorless star-shaped aggregates of plates or long prisms. 

 On slowly concentrating its aqueous solution it crystallizes in large 

 colorless prisms with pointed ends, being often arranged in star- 

 shaped bundles. It is, however, so soluble in water that it is more 

 expedient to crystallize it from water with addition of alcohol. 



The substance was free from bases, also free from nitrogen and 

 sulphur, but it contained phosphorus in organic combination. 

 Analysis showed that it was inosite monophosphate, C 6 Hi 3 9 P, ^r 

 C6Hc(OH)r,0"PO(OH)2. On cleavage either with dilute sulphuric 

 acid at 120° or higher or with 10 per ct. ammonia at 150° in a 

 sealed tube it decomposes into inosite and phosphoric acid. 



Inosite monophosphate has not been known previously, so far 

 as we are aware, and we believe that this is the first time that it 

 has been isolated. 



In connection with the " phytin " problem it is interesting to note 

 that a compound like inosite monophosphate exists in nature. 

 Clarke 3 in a recent paper reports the isolation from wild Indian 

 mustards of certain crystalline strychnine salts of what appears 

 to be inosite tetra- and diphosphate in addition to inosite hexa- 

 phosphate. It appears probable, therefore, that in certain plants the 

 organic phosphoric acids may be present not only as phytic acid 

 or inosite hexaphosphate, C 6 Hi 8 2 4P6, but also as lower phosphoric 

 acid esters of inosite. From wheat bran, for instance, we have been 

 unable to isolate any inosite hexaphosphate. The insoluble barium 

 salts of the organic phosphorus compound obtained from this 

 material are evidently mixtures of various organic phosphoric acids, 

 either lower inosite phosphates or phosphoric acid esters of other 

 carbohydrates. However, we have been unable, so far, to separate 

 any homogeneous substance from this mixture. 



The isolation of inosite monophosphate only succeeded because 

 its properties are so different from those of the other organic phos- 

 phoric acids which exist in wheat bran — for instance, its easily 

 soluble barium salt permitted its separation from the other acids 

 which give insoluble barium salts. 



*Jour. Chem. Soc. 105: 535. 1914 



