OP ARTS AND SCIENCES. 211 



VI. 



CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 



HARVARD COLLEGE. 



ON CERTAIN SUBSTANCES OBTAINED FROM 



TURMERIC. 



By C. Loring Jackson and A. E. Menke. 



Presented May 29, 1883. 



Owing to the difficulty of preparing curcumin, and the very unman- 

 ageable nature of the products obtained from it and from turmerol, 

 we have not made as much progress in the study of these substances 

 as we had hoped. In fact, we should not publish our results at the 

 present time, were it not that we cannot continue the work together 

 at all, and neither of us will be able to return to it for at least a year ; 

 we have therefore decided to collect in the following papers all the 

 results we have obtained up to this time, although many of them are 

 very fragmentary, and others consist only in indications which may 

 prove useful in future work. 



IV. CURCUMIN. 



Action of Acetic Anhydride on Curcumin. 



Monacetcur cumin. Ci^H]3(C._,H„0)0^. This substance is formed 

 by the action of acetic anhydride and fused sodic acetate on cur- 

 cumin, probably also by the action of acetylchloride. As has been 

 stated in a previous paper,* it forms an uninviting brown resin, which 

 we have not as yet succeeded in bringing into a crystalline condition ; 

 but nevertheless it can be obtained in a state of purity by the following 

 method : Curcumin is heated on the water-bath with a slight excess 

 of acetic anhydride and a little fused sodic acetate, for about sixteen 

 hours, in a flask with a return-cooler ; the dark brown viscous product 

 is then dissolved in a little glacial acetic acid, and precipitated with 

 water ; after repeating the solution in acetic acid, and precipitation 



* These Proceedings, Vol. XVU. p. 123. 



