Fluorescence golden yellow

Chelerythrine crystallises from alcohol in colourless, prismatic leaflets, m.p. 207°, containing one molecule of alcohol. The alkaloid absorbs carbon dioxide from the air, becoming yellow. The solutions fluoresce blue when the alkaloid is contaminated with its oxidation product, which is formed by mere exposure of solutions to air. The salts, which are quaternary, are intensely yellow. The hydrochloride, B. HCl. HjO, forms citron-yellow needles, and the sulphate, B. H2SO4.2HjO, golden-yellow needles, sparingly soluble in water the platinichloride, B2. HaPtCl. ... 

Levy5 has shown that two isomeric varieties of the pentahydrate exist, analogous to the two isomerides of the tetrahydrate of barium platinocyanide. The a-salt may be described as golden yellow with green fluorescence on the pyramid faces, whilst the (3-salt shows a green fluorescence on all faces, which is particularly intense on the tops of the crystals. The crystalline characters of the two isomerides are identical. 

After prolonged boiling to remove all the ammonia the solution is allowed to crystallise, when the salt separates out in long rhombic needles, density 7 2-4548 at 16° C. Upon exposure to air the crystals effloresce, and at 120° C. lose three molecules of water, becoming pale golden yellow. The crushed crystals are sulphur-yellow in colour, but the crystalline faces exhibit a blue fluorescence. When dehydrated at ordinary temperatures the colour becomes reddish yellow. On heating, the salt becomes white, then yellow, and finally melts at 400-600° C. It is soluble in cold water, easily so in hot, as also in alcohol and ether. Dilute mineral acids do not affect it, hut concentrated sulphuric acid effects the precipitation of platinous cyanide. 

B. Mix 3 drops of sample with 5 mL of a 1 300 solution of nitric acid glacial acetic acid in a dry test tube, and place the tube in a beaker of boiling water. A blue color appears within 5 min, which, on continued heating, deepens and shows a copper-colored fluorescence, and then fades, leaving a golden yellow solution. 

Golden yellow cryst. from EtOH or AcOH. M.p. 344°. Spar. sol. EtOH, AcOH. Sols fluoresce blue. Soda-lime at 400° — 2-methyl-anthracene. 

Dye for silk, cotton, wool, leather, paper. Dye for inks fluorescence probe has some bacteriostatic activity. Golden-yellow plates -h H2O (H2O). Spar. sol. cold H2O. Mp 267°. 

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