158 CHEMISTRY OF THE PROTEIDS CHAP. 



and Zangerle, 1 by Zanetti, 2 Frankel, 3 and Jacewicz, 4 Steudel, 5 Panzer/ 5 

 Leathes, 7 and Neuberg and Heymann. 8 



Baisch 9 discovered in 1894 an amino-hexose in urine, which is in 

 all probability identical with the glucosamin which reacts with Ehrlich's 

 test. Ehrlich's reaction with |?-dimethyl-amino-benzaldehyde, which, 

 according to Miiller, is a glucosamin-reaction, is dealt with on p. 10. 



Muller and his pupils have prepared glucosamin by benzoylising 

 solutions containing glucosamin with benzoylchloride and caustic soda, 

 and subsequently converting the resulting product, with hydrochloric 

 acid under pressure, into a soap. Steudel coupled the glucosamin 

 with phenyl-isocyanate, and then converted the newly-formed body^: 

 boiling with acetic acid into the very slightly soluble anhydrmer, 

 Neuberg and Heymann 8 employed bromphenyl-hydrazin. According 

 to E. Fischer and Leuchs, 10 glucosamin has the formula 



H H OH 



CH 2 (OH) - C - C - C - CH(NH 2 )COH 

 OH OH H. 



It is therefore a derivative of dextrose. Only the stereo-chemical 

 position of the amino-group is as yet uncertain. It is identical with 

 the above mentioned glucosamin, which Ledderhose 11 prepared from the 

 chitin of arthropods. E. Fischer considers it to be a link between the 

 carbohydrates and the oxy-a-amino-acids. " As the latter occur fairly 

 abundantly in proteids, glucosamin forms to a certain extent a bridge 

 between carbohydrates and proteids." Glucosamin is not fermentable 

 with yeast, and is not, or only slightly, affected by the oxidising and 

 dissociating ferments of mammals (Fabian, 12 Frankel and Offer 13 and 



1 H. Weydemann, Tierisches Gummi aus Eiweiss: Dissert., Marburg, 1896; J. 

 Seemann, Reduzierende Substanzen aus Huhnereiweiss : Dissert., Marburg, 1898; 

 Zangerle, Munch, medizin. Wochenschr. 1990, Nr. 13. 



2 C. U. Zanetti, Ann. di Chim. e Fermac. 12. (1897) ; in Holy's Jahresbericht 

 f. Tierchemie, 27. 31 (1897). 



3 S. Frankel, ' Spaltungsprodukte des Eiweiss bei Verdauung,' Monatsh. /. Chem. 

 19. 747 (1898). 



4 M. Jacewicz, Dissert. Petersburg (Russian), from Maly's Jahresbericht f. 

 Tierchemie, 26. 8 (1896). 



5 H. Steudel, Zeitschr. f. physiol. Chem,. 33. 223 (1901), 34. 353 (1901). 



6 T. Panzer, ibid. 28. 363 (1899). 



7 J. B. Leathes, Arch. f. experiment. Path. u. Pharmakol. 43. 245 (1899). 



8 C. Neuberg and F. Heymann, Jfofmeister's Beitrdge 2. 201 (1902). 

 n K. Baisch, Zeitschr. f. physiol. Chem. 19. 339 (1894). 



10 E. Fischer and H. Leuchs, Ber. d. deutsch. chem. Ges. 36. I. 24 (1903). Here 

 also summary of literature. 



11 G. Ledderhose, Zeitschr. f. physiol. Chem. 2. 213 (1878). 

 " R. Fabian, ibid. 27. 167 (1899). 



13 S. Frankel and Offer, Zentralblatt f. Physiologie, 13. 489 (1899). 



