a a saa a te on SR RAEN a, 
| CHEMICAL PREPARATIONS: AND DRGs: este 71 
“Se _ Some time ago, Pp. Pavialle and A. AibEyy eve painted out that the use of 
thy ymol, which in itself has a strongly hzmolytical action, as a preservative especially 
q for” vegetable extracts, has often led to erroneous assertions in that the hzmolytical 
action of the thymol has been described as a property of the substance under in- 
, _ vestigation. The same applies to the surface tension of urine to which thymol had 
__been added. Derrien and Colombier?), who have gone more closely into the matter 
3 ‘and have studied the drawbacks of the various substances recommended for the 
a -preservation of urine, call attention to the fact that urine preserved with thymol shows 
= a reduction of the surface tension, whereas Hays reaction*®) then always gives a 
DS positive result. Said reaction must therefore be applied cautiously if the urine tested 
_ has been preserved with thymol. Camphor exercises the same disturbing influence, 
z although in a lesser degree. | : | 
_ On page 101 of our Report of October 1917, we mentioned a communication of 
_ H.-P. Goodrich?), who recommends a saturated aqueous thymol solution as a denti- 
frice. According to J. T. Hall*), thymol is not at all appropriate for the purpose, as it 
4. acts far too strongly and has an injurious effect upon the gums, if used for any length 
z of time. For that reason, Goodrich now recommends to dilute the thymol os 
se especially during the warm part of the year. 
a | 
3 > By action of iodine on thymol, there results a body termed “aristol”, regarded as 
e a derivation of dimolecular thymol®). The discoverers, Messinger and Vortmann’), 
Pz expressed themselves as to the structure of aristol only with reserve. By acting with 
is iodine and potassium iodide on an alkaline solution of thymol, CH, , fe SCH 
y a red iodothymol is formed, which on heating, or keeping in nes ~ 
the dry state, splits off part of its iodine and passes over into © : 
_ a pale yellow, equally iodinated body. The red iodothymol was Oj O= 
taken by Messinger and Vortmann to be a iodinated derivative Bc Se 
of a thymol ester of hypoiodous acid of the formula: — Csi, CsA: 
This theory, according to J. Bougault*), does not agree with the facts. On 
_ Saponification, for instance, aristol does not yield hypoiodous acid; experimental details, 
ree TREN ih 
_however, are not published. Bougault believes aristol to be a doubly iodinated quinone 
_ derivative of a dimolecular thymol, possibly of the formula: — CH, CH, 
In Bougault’s opinion, there exists only one aristol, the “ ase 
yellow preparation; the red body being the yellow product / raat Sa 
coloured by free iodine and easily splitting off iodine. He YW nos H 
regarded aristol as a stable body, the assumption that. its Cos ~ 
therapeutical value is based on the easy liberation of iodine, 
_ being erroneous, the action depending merely on its antiseptic properties. 
ale | 
wr 
Tolu Balsam. A publication of G. C. van Walsem’) refers to embedding materials 
of a higher refractive power, especially balsam of tolu. It had been observed that 
preparations kept in Canada balsam lost considerably in comparison with the preli- 
_minary examination in oil of cloves. The cause was found to be that the Canada 
wm te ‘Ww 
1) Bull. Sciences pharmacol. 28 (1916), 193, 266; Report October 1917, 105. — 2) Bull. Soc. chim. IV. 
21 (1917), 133. — %) Sprinkling flowers of sulphur on the urine; the sulphur sinks to the bottom if bile 
acids are present. — +) British medical Journ. 1917, 1. 473; Chemist and Druggist 89 (1917), 376. — 5) British 
medical Journ. 1917, ll. 99; Chemist and Druggist 89 (1917), 783. — *) Comp. Bericht April 1890, 54. — 
_) Berichte 22 (1889), 2316. — *) Journ. de Pharm. et Chim. VII. 17 (1918), 221. — %) Zeitschr. f. wiss. Mikrosk. 
 B4 (1918), 154; Chem. Zentralbl. 1918, |. 771. 
+ 
hal apart FN RG OE De 
