from the GNU version of the Collaborative International Dictionary of English
- adj. Pertaining to, or derived from, weld (Reseda luteola).
- adj. Pertaining to, or designating, an acid resembling luteolin, but obtained from the flowers of Euphorbia cyparissias.
from The Century Dictionary and Cyclopedia
- Noting an acid, a yellow compound, C20H20O12 (?), resembling luteoleine, contained in the flowers of Euphorbia cyparissias. It crystallizes in slender needles, sublimes at 220° C., and melts at 273–274° C.
Sorry, no etymologies found.
Hydrolysis of digallic acid yields gallic acid; oxidation, on the other hand, ellagic acid and luteic acid (Luteo Säure), which can be separated by shaking with pyridine.
After about thirty hours a reddish powder deposits, from which ellagic acid may be extracted with pyridine; the mother-liquor on being concentrated yields luteic acid.
Ellagic acid is also obtained by heating luteic acid in a 10 per cent. soda solution.
When luteic acid is treated with diazomethane, it yields the methyl ester of pentamethoxybiphenylmethylolidcarboxylic acid.
Hydrolysis of leucogallic acid yields gallic acid and gallic aldehyde; oxidation by means of hydrogen peroxide yields ellagic acid and luteic acid, and oxidation with potassium persulphate and sulphuric acid, in acetic acid solution, yields purpurotannin (see below) [Footnote:
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