Terpin Hydrate

TERPIN HYDRATE, Terpinumhydratum(VI), * a product of the addition of a water molecule to menthane-1,8-diol, C₁₀ H₁₈ (OH)₂·H₂O, a diatomic tertiary alcohol (glycol) of the terpene series with the following structure: _/0(OH)-CH,

| n.s - ch - n_as\/ch₂ ch n.o ch₂ -CH₂ C(OH)(CH₃) CH₃.C(OH).CH₃ Colorless, transparent, rhombic crystals, melting at 121°, almost odorless, slightly bitter taste. Soluble in 250 parts of cold water and in 34 parts of boiling water, in 10 parts of cold and in 2 parts of boiling alcohol; slightly soluble in ether (100 parts), chloroform (200 parts) and turpentine, easily soluble in glacial acetic acid. When carefully heated to 100°, it sublimes in the form of beautiful needles. At 100°, and even at ordinary temperature over H₂SO₄, it loses water and turns into terpin. Upon adding a few drops of sulfuric acid to a hot aqueous solution (1:50), the liquid becomes cloudy and a strong aromatic odor appears (terpineols, cineole, dipentene, etc. are formed). It is obtained by acting on turpentine with nitric acid (in the presence of alcohol); instead of nitric acid, sulfuric or hydrochloric acid can also be used. T. has an action similar to turpentine oil, but is much better tolerated by the body, which is why it is quite readily taken internally for bronchitis (as an expectorant) in doses of 0.2 to 0.3 g several times a day in powders or pills; for whooping cough, according to the proposal of Manasse, it is used in doses of 0.5-1.0 once a day. T. is also used as a diuretic (Raphael). According to the observations of Lepine, in small doses T. increases bronchial secretion and thins it, thereby making the discharge of sputum easier. When the dose is increased, for example to 0.8-1.0, on the contrary, secretion ceases, since T. causes constriction of the blood vessels of the bronchial mucosa and reduces or even stops the bronchial-mucous secretion. It has no effect on the heart and on the digestive tract. It has almost no effect on healthy kidneys, but in some pathological conditions (e.g. in chronic nephritis), when administered in large doses, it aggravates the process and can cause bloody urine and even anuria. a. hypzBerg.