448 BROOKS. 



the constitution of this dye has been elucidated thoroughly by W. H. Perkin 

 jr., Kostanecki, Lampe and others, further investigation of it was not attempted. 



Brazilin, or brazilem, is not a fast dye and has the objection of being 

 very sensitive to acids and alkalies. For this reason its uses are very 

 restricted and it is probably only a question of time until it is entirely 

 supplanted by synthetic dyes. 35 



THE COLORING MATTER OE NARRA WOOD. 



In an examination of the coloring matters occuring in certain Phil- 

 ippine woods, it was noticed that the well-known narra wood, Ptero- 

 carpus spp., on treating with water yielded a solution which, on the 

 addition of a small amount of alkali, developed a beautiful, bluish- 

 green fluorescence. When a small quantity of the wood was extracted 

 with alcohol, the dark, red solution on cooling deposited crystals. What 

 appeared to be a crystalline fluorescent dye proved on further examina- 

 tion to be a mixture of a resin, a tannin, an amorphous, red coloring 

 matter, two colorless crystalline bodies and a yellow, fluorescent sub- 

 stance. The red coloring matter is closely related to, but not identical 

 with, the "santalin" obtained by Weyerman and Haffely 36 from the 

 closely related species Pterocarpus santalinus L. f., of India. 



The red coloring matter of narra was isolated in the following manner. The 

 wood shavings were extracted with alcohol, the alcoholic extract concentrated 

 and three volumes of water added. The solution was cooked until the alcohol 

 had almost completely been removed. The solution was then decanted from the 

 dark, red, amorphous mass. The aqueous extract contained the tannin and the 

 greater part of the fluorescent substance. The brown, amorphous residue was 

 then boiled under a return condenser with about five parts of chloroform, which 

 removed the crystalline substances and resin. 



The red coloring matter thus obtained was a dark, red; amorphous 

 powder, easily soluble in glacial acetic acid, phenol and alcohol, but 

 insoluble in carbon disulphide, chloroform, benzene, ligroin and ether. 

 It could not be obtained in a crystalline state. 



Weyermann and Haffely describe santalin as a body crystallizing in microscopic 

 fed prisms and melting at 104°. Franchimont 37 was unable to obtain it in 

 crystalline form. Weyermann and Haffely assign to it the formula 15 H 14 O 6 

 while Franchimont advances the formula C 17 H 10 6 for the amorphous preparation. 

 Bolley M gives several formulae all having twenty-seven carbon atoms. A. G. 

 Perkin S9 gives the formula C 30 H 27 O 10 -K for the potassium salt which is pre- 

 cipitated by alcoholic potassium acetate. J. C. Cain and May 40 have recently 



35 Rupe, H. Chemie der Naturliehen Farbstoffe. Braunschweig (1900), 141. 



36 Ann. d. Chem. (Liebig) (1850), 74, 2,26. 



VjBer. d. deutschen chem. Ges. (1879), 12, 14. 



™ Ann. d. Chem. (Liebig) (1847), 62, 150. 



w Journ. Chem,. Soc. London (1899), 75, 443. 



i0 Joum. Soc. Chem. Ind. (1909), 28, 697. 



