524 SCIENTIFIC RECORD FOR 188"2. 



constitution, CO (NH)2 C3 H4. It forms a white amorphous substance, 

 slightly soluble in alcohol, ether, chloroform, aud carbon-disulphide. 

 Dr. Leeds points out some irrational conclusions in Schiff's paper, and 

 accounts for them by presuming that Schifi" operated upon imperfectly 

 purified material. {Berichte d. chem. Gcs., xv, p. 1159.) 



Synthesis of Uric Acid. — This interesting synthesis has been accom- 

 plished by Prof. Johann Horbaczewski. Pure, finely powdered glyco- 

 coll (made from hippuric acid) is mixed with ten parts of pure urea (made 

 from ammonium cyanate) and heated in a flask to 200^ to 230° C, until 

 the material becomes brownish-yellow and viscous. After cooling the 

 mass is dissolved in diluted potassium hydroxide, saturated with ammo- 

 nium chloride, and precipitated witha mixture of ammoniacal silver 

 nitrate and magnesia mixture. The precipitate, which contains the uric 

 acid, is well washed with ammonia water and treated with potassium sul- 

 phide. The filtrate is then over-neutralized with hydrochloric acid and 

 boiled down to a small bulk. The raw material thus obtained is purified 

 by solution in potassium hydroxide, and after repeating the operation, 

 the yellowish crystalline powder is washed with alchohol, dried with 

 carbon disulphide (to remove the sulphur), aud finally with ether. This 

 purified material exhibits all the x^roperties and reactions of uric acid. 

 The author is engaged in a further study of this synthetical reaction. 

 {Berichte d. chem. Ges. xV; p. 2678.) 



Synthesis of a new Amido-Acid analogous to Hippuric Acid. — By the 

 action of silver glycocollate on benzoylchloride, Th.Curtius has obtained 

 three acids, ordinary hippuric acid, hippurylglycocoll, and a third of un- 

 known constitution having the empirical formula CioH,, N3O4. The 

 hippurylglycocoll or hippurylamidoacetic acid crystallizes from hot 

 water in rhombic tables or needles which melt without decomposition 

 at 206°.5 C. The new acid crystallizes in microscopic needles which 

 become brown when heated to 230°, and are decomposed at 240° C. 

 {Journal pralc. Chem. N. F., xxvi, p. 145.) 



Sy7ilhesis of Tyrosine. — Tyrosine forms a crystalline nitrogenous body 

 existing in the animal organism (spleen, liver, urine, &c.), produced by 

 the decomposition of albuminoid substances. It has long been studied 

 by chemists; Liebig obtained it by acting on decomposing caseine with 

 melted potash, Miiller found it in putrefying yeast, Hinterberger pre- 

 pared it by boiling oxhoru with sulphuric acid, and its constitution has 

 been discussed by several authors. In 1869 L. Barth pointed out that 

 tyrosine could be regarded as a parahydroxyphenylamidopropionic acid, 

 but his attempts to prepare it, as well as the proposed reactions of Beil- 

 stein and Kuhlberg, were unsuccessful. 



Erlenmeyer has been engaged for several years in experimenting in 

 this direction, and with the assistance of Dr. A. Lipp has at length 

 accomplished this interesting synthesis. The process is as follows : 



