6 CAPSANTHIN 245 



Solvent Absorption maxima 



Carbon disulpbide 508 477 vajx 



Pyridine 493 463 m/z 



Benzene 492 462 m^ 



Chloroform 486 456 m^ 



Ethanol 478 448 m/x 



Capsanthin diacetate C44H62O5: 



This compound was prepared by Zechmeister and von Cholnoky^^ by 

 treating capsanthin with acetyl chloride in pyridine solution. The diacetate is 

 purified by chromatography on calcium carbonate from petrol solution and by 

 crystallisation from methanol. It separates in plates, m.p. 146.5° (corr.). 



The pigment is very soluble in chloroform, ether, carbon disulphide and 

 benzene, and somewhat less soluble in methanol. On partition between methanol 

 and petroleum ether, the ester is found quantitatively in the upper layer. 



Capsanthin dipropionate C^gHggOj: 



The dipropionate is prepared in the same way as the diacetate. It separates 

 from a mixture of ethanol and carbon disulphide, or from ethanol alone, in 

 crystals, m.p. 140°. 



Capsanthin dicaprate C60H94O5 : This compound is prepared in the. same 

 way as capsanthin diacetate^^. M.p. 109° (corr.)*. The ester crystallises from a 

 mixture of benzene and methanol in red plates with a violet tinge. It is readily 

 soluble in petroleum ether, chloroform, ether, carbon disulphide and benzene. 

 It is much less soluble in ethanol than the diacetate. [a\l%,^ == —61° in hexane. 



Capsanthin diniyristate CegHjioOg : The ester crystallises from a mixture of 

 benzene and methanol in red needles, m.p. 88°. The solubihty is similar to that 

 of the dicaprate, except that the dim^-Tistate is insoluble in alcohols. 



Capsanthin dipahnitate C^2^^iS^b '■ The dipalmitate is prepared and purified 

 in the same way as the diacetate^*. It crystalhsed from a mixture of benzene 

 and methanol in bordeaux-red plates, m.p. 95° (corr.)** ^^. For the absorption 

 spectra in different solvents compare the original communication by Zech- 

 meister and VON Cholnoky**. 



Capsanthin distearate C^qHI^^S^^: This compound is prepared by the same 

 method as the other esters^^. M.p. 84°. The distearate shows great similarity to 

 the dipalmitate both in appearance and solubility. 



Capsanthin dibenzoate Cg^HggOg: This ester crystallises from a mixture of 

 benzene and methanol in red needles, and from a mixture of carbon disulphide 



* L. Zechmeister and L. v. Cholnoky, Ann. 487 (1931) 210, previously reported 

 m.p. 102° (corr.). 

 ** L. Zechmeister and L. v. Cholnoky, Ann. 509 (1934) 286, reported m.p. 92° 

 (corr.). 



References p. 253—255. 



