A light orange, crystalline precipitate formed; m. p. 205-210 0 (decomp.); yield, 1.4 g. The product was readily soluble in water.Anal. Caled, for CioHhN5-2H20-HC1: Cl, 12.8. Found: Cl, 12.07.In the case of the bis-guanidine derivative a solution of the monohydrochloride was prepared by dissolving a weighed amount in the calculated volume of standard hydrochloric acid and diluting to a definite concentration. This solution was used for the pharmacological tests which were carried out according to the international methods adopted for the standardization of insulin.10 Summary Two derivatives of aminoguanidine have been prepared and their hypoglycemic action studied. Neither compound exerted an insulin-like action. Hypoglycemia was produced only when the amount of the compound administered approached the toxic dose, but this drop in blood sugar was due to shock to the rabbit's system as shown by the fact that injection of glucose did not cause recovery.

MICRO-DETERMINATION OF SULFUR BY FUSION 1291Experimental The general methods of preparation of the various intermediates have been described in previous articles in this series.

emulsion is formed it should be treated with charcoal while hot and filtered. Two grams of bromoacetic acid was dissolved in 10 cc. of water and 2 drops of phenolphthalein added; 10% potassium hydroxide solution was then added until a permanent pink color was obtained. The two solutions were then mixed and gently boiled for ten minutes. A small portion of norite was then added and the boiling continued for one minute. The mixture was filtered through a fluted filter while hot. The filtrate was allowed to cool and neutralized with concentrated hydrochloric acid. An oil separated which solidified on standing. The crystalline product was then recrystallized from water, or a mixture of benzene and ligroin. The colorless crystals were then dried in an air-bath at 110°.The authors desire to express their appreciation to Professor Wm. C. MacTavish for the facilities placed so generously at their disposal. SummaryThe intramolecular rearrangement of isopropyl w-cresyl ether, under the influence of a mixture of glacial acetic acid and concentrated sulfuric acid, was studied; thymol and w-methyl-^-isopropylphenol were the products obtained, thus furnishing a new synthesis of thymol.Methylthymol, ethylthymol and chlorothymol were prepared in a similar manner, by the rearrangement of the corresponding isomeric ethers, illustrating that the rearrangement of secondary alkyl phenyl ethers is a general reaction.Theories underlying such intramolecular rearrangements were discussed and a reaction mechanism based upon the considerations of Lapworth and Latimer was proposed.New York, N. Y.

SOME NEW ESTERS OF ERGOSTEROL 2015 2. The presence of a third sterol (m. p. 120-125°, [ct]D -2°, acetate, m. p. 121-124°) is established.

Callow1 has recently showed that ergosterol from yeast contains adihydroergosterol. We previously showed this for ergosterol from ergot.2 In the preceding paper we have found this substance to be the preponderant sterol in the filtrate from ergosterol preparations.Previously it had been noted in this Laboratory that fine samples of -ergostenol were regularly prepared from very impure samples of ergosterol. In fact there is no necessity for elaborate purification of ergosterol in proceeding with the preparation of -ergostenol because, as we know, the impurity -dihydroergosterol reduces to the same end-product.