220 



APPENDIX 



Composition 



Cyanin 



Cyanidin 



C 27 H 31 19 C1 



) ; C 15 H U 6 C1 . H 2 ; water C 41 H 39 21 C1 

 | mol. H 2 given off in given off with difficulty 

 vac. at 105 



Delphinin 



12H 2 ; 



2H 2 held fast 



Components 



Crystallisation 



Colour in dilute acid ... 



Solubility in water and 

 alcohols 



Reaction with soda 

 Reaction with FeCl 3 



Isomerisation 

 Pseudobase 



C 15 H U 6 C1 + 2 glucose 



Rhomboidal plates (grey 

 violet); M.P. 203-204 



Red tinged violet 



Almost insol. in cold 

 water ; readily in hot ; 

 v. difficultly sol. in 

 alcohol 



Violet, then blue 



Blue (in alcohol) ; violet 

 (in water) 



Readily isomerises 



Long needles (brown-red) 

 or platelets ; M.P. 220 



Red tinged violet 



Insol. in water ; v. readily 

 sol. in alcohols 



Violet, then blue 



Blue (in alcohol); violet 

 (in dil. alcohol) 



C 15 Hj 2 O 7 . H 2 (X crystal- 

 line 



C 15 H U 0,C1 + 2 glucose 

 + 2 j>-oxybenzoic acid 



Prismatic tables (bluish- 

 red); MP. 200-203 



Blue-red 



Decomposed by water 

 with pptn. of violet 

 base ; difficultly sol. 

 abs. alcohol; sol. in 

 methyl alcohol 



Violet, then blue 



Blue (in water and alcohol) 



Does not isomerise 



Composition 



Components 

 Crystallisation 



Oenidin 



C 17 H 15 7 C1. 1JH 2 0; 

 mol. water given off 

 first in vac. at 100 



Prisms or needles (brown) 



Colour in dilute acid ... Brown-red 



Solubility in water and 

 alcohols 



Reaction with soda 

 Reaction with FeCl 3 



Readily sol. in water; 

 v. readily sol. in methyl 

 and ethyl alcohols 



Violet 



No reaction 



Malvin 



29 ri35O 17 Cl . 8rI 2 O 

 water-free in desiccator 



C 17 H 15 7 C1 + 2 glucose 



Long prisms and needles 

 (purple-red) ; M.P. 165 



Blue-red 



Difficultly sol. in water; 

 readily sol. in methyl 

 alcohol; less in ethyl 

 alcohol 



Blue 



No reaction 



Malvidin 



C 17 H 15 7 C1.2H 2 0; 



1 niol. water given off 

 with difficulty 



Long prisms and needles 

 (olive-brown) ; does not 

 melt at 300 



Brown-red 



Considerably sol. in water; 

 readily in ethyl alcohol ; 

 difficultly in methyl 

 alcohol 



Violet, then blue 

 No reaction 



Isomerisation 



Readily isomerises 



