AMMONIA-DERIVATIVES AND THEIR COMBINATIONS. 467 



spond to Trommer's test and is susceptible only of sarcolactic-acid fermentation. 

 Evaporated to dryness with nitric acid, then with ammonia and calcium chlorid, 

 it leaves a rosy-red stain. 



AMMONIA-DERIVATIVES AND THEIR COMBINATIONS. 



The ammonia-derivatives are products of proteids, decomposition-products 

 of the tissue-metamorphosis of proteids. 



1. Amins, that is compound ammonias, which may be derived from ammonia 

 (NH 3 ) or from ammonium hydroxid (H 4 N, OH) by replacing one or all of the 

 atoms of H by carbohydrate-groups (alcohol-radicles) . The amins derived from a 

 single molecule of ammonia are designated monamins. Among these are methylamin, 



H IN, and trym'ethalamin, CH^N, known only as decomposition-products of 

 CH 3 } CH 3 f 



cholin (neurin) and of kreatin. Neurin occurs in lecithin in complex combination. 

 The lecithins are described on p. 463 and the diamins are discussed on p. 305. 



2. Amids, that is derivatives of acids in which NH 2 is substituted for the 

 hydroxyl (HO) of the acids. Urea, CO(NH 2 ) 2 , the diamid of CO 2 is the principal 

 end-product of the tissue-metamorphosis of the nitrogenous constituents of the 

 body. Carbon dioxid containing water is CO(OH) 2 , in which both OH-atoms 

 are replaced by NH 2 , thus CO(NH 2 ) 2 . 



3. Amido-acids, that is nitrogenous combinations exhibiting partly the 

 character of an acid, and partly that of a feeble base, in which H-atoms of the 

 acid-radicle are replaced by NH 2 or substituted ammonia-groups. 



(a) Glycin (amido-acetic acid, glycocol, gelatin-sugar) results on boiling gelatin 

 with dilute sulphuric acid. It is present in the cornea, which contains, besides, 

 chondrin. It has a sweet taste (gelatin-sugar), behaves like a feeble acid, but 

 unites also as an amin-base with acids. It occurs as glycin + benzoic acid = hippuric- 

 acid in the urine (it has also been prepared artificially) , and as glycin + cholic 

 acid = glycocholic acid in the bile. (6) Leucin (amidocaproic acid) has been found 

 pathologically in pus and in the atheromatous matter of sebaceous cysts, generally 

 in combination with tyrosin. (c) Serin (amidolactic acid) is obtained from silk- 

 gelatin, (d) Blood-alinin (amidovalerianic acid) . (e) A spartic acid (amidosuccinic 

 acid) . (/) Glutamic acid (amidopyrotartaric acid) is obtained in the decomposition 

 of albuminates. Aspartic acid can be obtained from asparagin by boiling with 

 acids and the splitting off of ammonia. Asparagin is formed largely in the vegetable 

 kingdom from albumin and has been prepared artificially, while in the animal 

 body it is transformed into urea and uric acid, (g) Cystin (amidolactic acid), in 

 which O is replaced by S, is strongly levorotatory. (h) Taurin (amido-ethyl- 

 sulphuric acid) occurs, besides in a number of glands, particularly in combination 

 with cholic acid as taurocholic acid in bile. It has also been prepared artificially. 

 (i) Tyrosin (paraoxyphenylamidopropionic acid, prepared synthetically) occurs 

 together with leucin in the presence of pancreatic digestion. It may occur patho- 

 logically in the urine. It is abundant in dahlia-bulbs. 



There are related to the amido-acids further: (a) Kreatin, methylguanidin- 

 acetic acid, CH 9 N 3 O 2 , which is present in muscle, brain, blood, and' urine, and 

 has been prepared artificially. Boiled with baryta-water it takes up water 

 and is decomposed into urea; (6) Sarcosin (C 3 H 7 NO 2 , methylamido-acetic acid). 

 When boiled with water or heated with strong acids in the presence of decomposing 

 substances kreatin is transformed into kreatinin with the loss of water; kreatinin 

 occurs in the urine. This strong base can be retransformed into kreatin by the 

 action of alkalies. 



4. Ammonia-derivatives in Part of Unknown Constitution. Uric acid. Allan- 

 loin results from the oxidation of uric acid by means of potassium permanganate. 

 It has been found, together with guanin and sarcin, also in the buds of Platanaceae. 

 Cyanuric acid has been found in dog's urine. Inosinic acid is present in muscle. 

 Guanin (C 5 H 5 N 5 O), together with adenin, xanthin and hypoxanthin, a decomposi- 

 tion-product of nuclein, occurs in traces in normal blood, in larger amount in 

 leukemic blood, and in considerable amount in embryonal muscle, as well as 

 in the liver, the spleen and the pancreas. It occurs, pathologically, in rapidly 

 growing neoplasms rich in nuclei, and in the muscles of swine suffering from 

 guanin-gout. It is transformed by nitrous acid into xanthin, by oxidation into 

 urea and when fed to animals it increases the elimination of urea. It occurs, 

 further, in guano, in the excrement of spiders, in the skin of amphibia and reptiles, 

 in the silver gloss of some fish (for example the herring) . Hypoxanthin or sarcin 



