See also:

• XANTHONE (dibenzo-y-pyrone, or diphenylene ketone oxide)

XANTHONE (dibenzo-y-pyrone, or diphenylene ketone See also:

• OXIDE

oxide)  , C13HiO2, in organic See also:

• CHEMISTRY
• CHEMISTRY (formerly "chymistry"; Gr. xvµela; for derivation see ALCHEMY)

chemistry, a heterocyclic See also:

• COMPOUND
• COMPOUND (from Lat. componere, to combine or put together)

compound containing the See also:

• RING (O.E. hring; a word common to Teutonic languages; and probably cognate with the Lat. circus, Gr. KtpKOS or KpLKOS, Skt'. chakra, wheel, circle, cf. also " harangue "); in art, a band of circular shape of varying sizes, made of any material and used f

ring See also:

• SYSTEM

system shown below . It is obtained by the oxidation of xanthene (methylene diphenylene See also:

• OXIDE

oxide) with chromic See also:

• ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid; by the See also:

• ACTION

action of See also:

• PHOSPHORUS (Gr. 4ws, light, sPEpety, to bear)

phosphorus oxycliloride on disodium salicylate; by See also:

• HEATING

heating 2.2'-dioxybenzophenone with concentrated sulphuric acid; by distilling fluoran with See also:

• LIME
• LIME (O. Eng. lim, Lat. limes, mud, from linere, to smear)

lime; by the oxidation of xanthydrol (R . See also:

• MEYER, CHRISTIAN ERICH HERMANN VON (18or-1869)
• MEYER, HEINRICH AUGUST WILHELM (1800-1873)
• MEYER, JULIUS LOTHAR (183o-1895)
• MEYER, KONRAD FERDINAND (1825-1898)
• MEYER, VICTOR (1848-1897)
• MEYER, [MARIE] PAUL HYACINTHE (184o- )

Meyer, Ber., 1893, 26, p . 1277); by boiling diazotized 2.2'-diaininobenzophenone with See also:

• WATER

water (Heyl., Ber., 1898, 31, p . 3034) ; by heating salol with concentrated sulphuric acid (C . Graebe, See also:

• ANN

Ann., 1889, 254, p . 280), and by heating See also:

• POTASSIUM [symbol K (from kalium), atomic weight 39.114 0=16)]

potassium-ortho=chlorobenzoate with See also:

• SODIUM [symbol Na, from Lat. natrium; atomic weight 23.00 (0=16)]

sodium phenolate and a small quantity of See also:

• COPPER (symbol Cu, atomic weight 63.1, H=1, or 63.6, O = 16)

copper See also:

• POWDER (through O. Fr. puldre, modern poudre, from Lat. pulvis, pulveris, dust)

powder to 180–190° C . (F . See also:

• ULLMANN, KARL (1796-1865)

Ullmann, Ber., 1905, 38, pp . 729, 2120, 2211) . It crystallizes in needles which melt at 173–174° and See also:

• BOIL

boil at 349–350° C., and are volatile in See also:

• STEAM
• STEAM (0. Eng. steam, vapour, smoke, cf. Du. steam; the origin is unknown)

steam . Its See also:

• SOLUTION (from Lat. solvere, to loosen, dissolve)

solution in concentrated sulphuric acid is of a yellow See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour and shows a marked See also:

• BLUE (common in different forms to most European languages)

blue See also:

• FLUORESCENCE

fluorescence .

The carbonyl See also:

• GROUP

group is not ketonic in See also:

• CHARACTER (Gr. xapareri7p, from xap&crew, to scratch)

character since it yields neither an oxime nor See also:

• HYDRAZONE

hydrazone . When fused with See also:

• CAUSTIC (Gr. rcavvraubs, burning)

caustic potash it yields phenol and salicylic acid . Mild reducing agents convert it into xanthydrol, the group > CO becoming > CH•OH, whilst a strong reducing See also:

• AGENT (from Lat. agere, to act)

agent like hydriodic acid converts it into xanthene, the group> CO becoming> See also:

• CH2
• CH2(OH)

CH2 . Phosphorus pentasulphide at 140–150° C. converts it into xanthion by transformation of > CO to >CS (R . Meyer, Ber., 1900, 33, p . 2580), and this latter compound condenses with See also:

• HYDROXYLAMINE, NH2OH

hydroxylamine to See also:

• FORM (Lat. forma)

form See also:

• XANTHONE (dibenzo-y-pyrone, or diphenylene ketone oxide)

xanthone oxime . All four mono-hydroxyxanthones are known, and are prepared by heating salicylic acid with either See also:

• RESORCIN (meta-dioxybenzene), C5H4(OH)2i one of the dihydric phenols. It is obtained on fusing many resins (galbanum, asafoetida, &c.)

resorcin, See also:

• PYROCATECHIN, or PYROCATECHOL

pyrocatechin or hydroquinone; they are yellow crystalline solids, which See also:

• ACT (Lat. actus, actum)

act as dyestuffs . The 1.7-di,hydroxyxanthone, known as euxanthone, is prepared by heating euxanthic acid with hydrochloric acid or by heating hydrouinone carboxylic acid with l3-resorcylic acid and acetic anhydride (S . Kostanecki, Ber., 1891, 24, p . 3983E C . Graebe, Ann., 1889, 254, p . 298) .

It is also obtained from See also:

• INDIAN

Indian yellow (Graebe, ibid.), formed in the urine of cows fed on See also:

• MANGO

mango leaves . It crystallizes in yellow needles which See also:

• SUBLIME (Lat. sublimis, exalted)

sublime readily . On See also:

• FUSION

fusion with caustic potash it decomposes with formation of tetrahydroxy-See also:

• BENZOPHENONE (DIPIENYL KETONE)

benzophenone, which then breaks up into resorcin and hydroquinone . The isomeric 1.6-dihydroxyxanthone, isoeuxanthone, is formed when 13-resorcylic acid is heated with acetic anhydride . Gentisein, or 1.3.7-trihydroxyxanthone, is found in the form of its methyl See also:

• ETHER, (C2H5)2O

ether (gentisin) in See also:

• GENTIAN

gentian See also:

• ROOT (late O.E. rot, adopted from Scand., cf. Norw. and Swed. rot, Dan. rod; the true O.E. word was wyrt, plant, represented in Ger. Wurz or Wurzel; the ultimate root is the same in both words, and is seen in Lat. radix)
• ROOT, ELIHU (1845– )

root; it is obtained synthetically by condensing phloroglucin with hydroquinone carboxylic acid . Xanthene, C15H1oO, may be synthesized by condensing phenol with ortho-cresol in the presence of See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium chloride . Its tetramethyl-diamino derivative, which is formed by condensing formaldehyde with dimethyl-See also:

• META

meta-aminophenol and subsequent elimination of water from the resulting See also:

• DIPHENYL (phenyl benzene), C6H5

diphenyl methane derivative, is the leuco See also:

• BASE

base of pyronine, into which it passes by oxidation . Cl(CHa)2N/\/\ o /\% 8 7/\/CO\, /~//CH\ \/\ /\/~3 5 4 Xanthone . Pyronine .