I BIXIN 263 



Quantitative extinction measurements are reported by Hausser and 

 Smakula^^. The fluorescence spectrum is described by Hausser, R. Kuhn 

 and E. Kuhn^*. 



Stable apo-i-norbixinal methyl ester CjsHggOg : 



CH3 CH3 GI13 CHg 



HjCOOC- CH=CH- C=CHCH=CH- C=CHCH=CHCH=C- CH=CHCH=C- CHO 



Apo-i-norbixinal methyl ester 



This ester is obtained by the controlled permanganate oxidation of stable 

 bixin^^. The stable aldehyde is also formed by the isomerisation of labile apo- 

 i-norbixinal methyl ester with iodine^^. It crystalHses in small prisms, m.p. 167°. 



Solvent Absorption maxima 



Carbon disulphide 509 478 m// 



Ethanol 487 456 m/f 



Petroleum ether 472.5 445 m^ 



Solvent Absorption maxima of oxime 



Carbon disulphide 509 478 m/i 



Ethanol 483 452 m// 



Petroleum ether 475 446 m// 



Stable apo-2-norbixinal methyl ester C20H24O3 : 



HaCOOC- CH=CH- C=CHCH=CH- C=CHCH=CHCH=C- CH=CH- CHO 



Apo-2-norbixinal methyl ester 



This ester is obtained by the controlled oxidation of stable methylbixin 

 with potassium permanganate^^. Only the oxime and semicarbazone, but not 

 the compound itself, has so far been obtained in a crystalline state. 



Solvent Absorption maxima 



Carbon disulphide 483.5 453 vufi 



Petroleum ether 450 424 m/z 



Solvent Absorption maxima of oxime 



Carbon disulphide 481 451 m^ 



Ethanol 459 mfj. 



Absorption maxima of semicarbazone 



Carbon disulphide 493 462 m^ 



Ethanol 471 m/z 



Apo-3-norbixinal methyl ester C^gHjaOg^^: 



CHs CI13 CHo 



I I I 



HsCOOC- CH=CH- C=CHCH=CH- C=CHCH=CHCH=C- CHO 



Apo-3-norbixinal methyl ester 

 References p. 2go-2g4. 



