General Description
Odorless white crystalline powder. Bitter taste. pH (saturated solution in water): 5.5-7.
Reactivity Profile
THEOBROMINE(83-67-0) may be sensitive to prolonged exposure to light. This chemical has weakly acidic properties, combining with bases to forms salts. THEOBROMINE(83-67-0) also has even weaker basic properties, combining with acids to form salts which are decomposed in aqueous solution. .
Air & Water Reactions
Insoluble in water.
Fire Hazard
Flash point data for this chemical are not available; however, THEOBROMINE is probably combustible.
Description
A purine alkaloid which is present in a number of plants, particularly Theobroma
coco and kola nuts. The alkaloid sublimes at 290°C and may be purified by this
method when it forms colourless, rhombic microcrystals. It is soluble in 1600
parts of H20 at 17°C, insoluble in cold Et20 or ligroin. It is a weak base and the
salts are decomposed by H20. The perchlorate forms colourless crystals of the
monohydrate which decompose at 271-3°C; the mercurinitrate is also crystalline
and has a melting point above 300°C. The mercury salt is obtained as colourless
crystals which darken at 29S-300°C and melt at 310°C. One imino group is
present yielding alkyl derivative, e.g. the N-methyl compound identical with
Caffeine (q.v.); the N~ethyl derivative, m.p. 164-SoC, forming an aurichloride,
m.p. 226°C; N-propyl, m.p. 136°C giving an aurichloride, m.p. 9SoC; N-butyl,
m.p. 119°C and the N-iso butyl, m.p. 129-130oC also giving an aurichloride,m.p. 97°C. The alkaloid also furnishes a methochloride as colourless rods, m.p.
320-340°C (dec.) which is very soluble in H20 and the methoaurichloride, m.p.
265°C (dec.).
Like Caffeine (q.v.) and Theophylline (q.v.), the alkaloid and its salts are
mild stimulants and also possess a diuretic action.
Chemical Properties
A methyl xanthine similar to caffeine. Theobromine has a bitter taste.
Chemical Properties
white to light yellow crystal powder
Occurrence
Reported found in cocoa bean, cocoa powder, cola nut and tea.
Uses
A metabolite of Caffeine
Uses
diuretic, bronchodilator, cardiotonic
Definition
ChEBI: A dimethylxanthine having the two methyl groups located at positions 3 and 7. It is a purine alkaloid derived from cocoa tree.
Hazard
Toxic by ingestion. Questionable carcinogen.
Flammability and Explosibility
Nonflammable
Purification Methods
It crystallises from H2O. Its solubility in H2O is 0.06% at 15o and 1.25% at 100o, and it is poorly soluble in organic solvents. It forms salts with heavy metals and is a diuretic, vasodilator and a cardiac stimulant. [Lister Purines Part II, Fused Pyrimidines Brown Ed, Wiley-Interscience pp254-225 1971, ISBN 0-471-38205-1, Beilstein 26 H 457, 26 I 135, 26 II 264, 26 III/IV 2336.]
References
Biltz, Max., Annalen, 423,320 (1921)
Dubosc., Chem. Zentr., IV, 956 (1932)
Gepner, Kreps., Chem. Abstr., 41,96 (1947)
Bohinc, Korber-Smid, J agodic., Farm. Vestn., (Ljubljana), 23, 143 (1972)
