TABLE 1.—MELTING POINT
| Ash | Ash | ||||
| 1 | 188.5–189.0 | 0.01 | 5 | 188.0–188.5 | 0.01 |
| 2 | 188.5–189.0 | 0.01 | 6 | 188.0–188.5 | 0.01 |
| 3 | 188.0–188.5 | 0.01 | 7 | 188.0–188.5 | 0.01 |
| 4 | 188.0–188.5 | 0.04 | 8 | 188.0–188.5 | 0.02 |
Barbital does not seem to form an insoluble salt with chlorplatinic acid; nor an ether-insoluble hydrochlorid or oxalate; nor an insoluble barium salt. It does not respond to many urea tests, and is not affected by urease as would be expected in light of the extensive investigations made on this enzyme by Van Slyke and Cullen.
As barbital is also sold in the form of tablets or mixtures, a reliable method for its quantitative determination in the presence of other substances is needed. Some experiments in this direction were made, but the press of other work did not permit their continuation. When time permits, this work will be resumed.
At the time of writing this article, licenses for manufacture had been granted by the Federal Trade Commission to the Abbott Laboratories, to Antoine Chiris Company, and to the Rector Chemical Company.
BARBITAL SODIUM (MEDINAL OR VERONAL-SODIUM)
Barbital sodium, formerly sold under the proprietary names “veronal-sodium” and “medinal,” is, as the former name suggests, the sodium salt of diethylbarbituric acid. Its therapeutic advantages are stated to be that more rapid results are obtained because of its increased solubility over barbital alone.[227] Barbital sodium should yield, according to theory, 11.19 per cent. of sodium and 89.31 per cent. of diethylbarbituric acid. A number of years ago, when “veronal-sodium” and “medinal” were being introduced, Puckner and Hilpert[228] found that these products yielded results corresponding closely to the theoretical amounts of sodium and diethylbarbituric acid. A recent examination of veronal-sodium, Merck, made for the Council on Pharmacy and Chemistry, showed it to be of the same composition as that previously reported.
Only one firm’s product has been submitted to the laboratory through the Committee on Synthetic Drugs, but because of the unsatisfactory results, it was not recommended for license, nor, as far as we are aware, has the firm investigated its anomalies.[229] The amount of moisture in this specimen was 0.04 per cent. It yielded 10.94 and 10.97 per cent, of sodium. Puckner and Hilpert found 11.02 per cent. of sodium in “medinal,” and 11.01 per cent. of sodium in “veronal-sodium.” The theoretical amount, according to the formula given for medinal by the proprietors (C2H5)2
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