250 



CARBOHYDRATES AND GLUCOSIDES [156-158 A. 



(Winterstein, Zeit. physiol. Ch. 21, 

 152) ; and in gum extracted from yeast 

 by lime or alkali (Hessenland, Zeit. d. 

 Ver. f. Riibenzuckerindustrie, 1892, 

 p. 67 1 ; Salkowski, Ber. 27, 497 ; Zeit. 

 physiol. Ch. 18, 506). 



The woody tissue of cycads and coni- 

 fers and (to a small extent) that of 

 EpJieclra distachya contains mannose- 

 yielding compounds (Bertrand, Comp. 

 Rend. 129, 1025). 



NOTE : For general distribution of mannan 

 in the wood of the sugar maple and throughout 

 the vegetable kingdom see Storer in the Bulletin 

 of Bussey Institution, III, No. 2, 1902. 



SYNTHETICAL PROCESSES. 



[A.] From formic aldeliyde [9l] 

 through a-acrose, &c., as under manni- 

 tol [61; A]. d-Mannonic acid gives 

 d-mannose on reduction with sodium 

 amalgam in acid solution (loc. cit.\ also 

 Fischer, Ber. 22, 2204). 



[B.] From glycerol [48] through a- 

 acrose, &c., as under mannitol [51 ; B]. 



[C.] From mannifol [5l] with laevu- 

 lose by oxidation (see under laevulose 

 [155 ; C]). Also by oxidation with 

 hydrogen peroxide and ferrous sulphate 

 (Fenton and Jackson, Trans. Ch. Soc. 

 75, 8). 



[D.] From tartaric acid [Vol. II] 

 through glycollic aldehyde and a-acrose 

 (see under mannitol [51; G]). 



[E.] Dextrose [154] gives mannose 

 (with Isevulose, glutose, and </>-fructose) 

 under the influence of alkali or lead 

 hydroxide (Lobry de Bruyn and Van 

 Eckenstein, Rec. Tr. Ch. 16, 257 ; 274). 



[P.] L&vulose [155] gives mannose 

 with other sugars under the same con- 

 ditions as above (Ibid. 14, 156 ; 203 ; 

 16, 274; 282; Ber. 28, 3078). 



157. Salicin ; Saligenin Glticosicle. 

 HO.CH 2 .C 6 H 4 .0(C 6 H n 5 ) 



NATURAL SOURCES. 



In bark and leaves of Salix helix, 

 S, ' pracox,' S. pentandra, and other 

 species. Occurs also in bark and leaves 

 of Populiis tremula, P. tremuloides , &c. 

 (Tischhauser, Ann. 7, 280), and in 



flower buds of Spirtea ulmaria (Buchner, 

 Ann. 88, 324). 



Occurs also in castoreum (Wohler, 

 Ann. 67, 360). 



NOTE : For full references and list of species 

 see under saligenin [55]. 



SYNTHETICAL PROCESS. 



[A.] From salicylic aldehyde [117] 

 and dextrose [154]. The latter is con- 

 verted into acetchlorglucose [C 6 H 7 OC1 

 (C 2 H 3 O 2 ) 4 ] (Colley, Comp. Rend. 70, 

 401 ; Ann. Chim. [4] 21, 363 : see 

 also Kb'nigs, Ber. 21, 2207 ; Fischer 

 and E. F. Armstrong, Sitz. Pr. Akad. 

 1901, 13, 316; F. v. Arlt, Monats. 22, 

 144; Skraup and Kremann, Ibid. 

 375; F. and E. F. A., Ber. 34, 

 2885). Salicylic aldehyde and acet- 

 chlorglucose in presence of potassium 

 ethoxide give the glucoside helicin 

 (Michael, Am. Ch. Journ. 1, 309 ; 

 Comp. Rend. 89, 355; Ber. 12, 2260; 

 14, 2100; 15, 1922 : see also Schiff, Ber. 



14, 2559)- 



Helicin on reduction with sodium 



amalgam or zinc and sulphuric acid 

 gives salicin (Lisenko, Zeit. [i] 1864, 

 577 ; Michael, Am. Ch. Journ. 5, 172). 



158. Fopulin ; Benzoylsalicin. 

 (C 7 H 2 )CH 2 .C 6 H 4 .0(C 6 H U 5 ) 



NATURAL SOURCES. 



In bark, leaves, and buds of Popuhts 

 tremula j P. nigra, P. pyramidalis, and 

 P. balsamifera (Braconnot, Ann. Chim. 

 [2] 44, 296; Berz. Jahresber. 11, 286; 

 Biot and Pasteur, Comp. Rend. 34, 

 606; Piria, Ann. Chim. [3] 34, 278; 

 44, 366; Ann. 81, 245; 96, 375; 

 Piccard, Ber. 6, 890 ; Hallwachs, Ann. 

 101, 372 ; v. Lippmann, Ber. 12, 1648 ; 

 Herberger, Arch. Pharm. 46, 104; 47, 

 250). 



SYNTHETICAL PROCESS. 



[A.] From salicin [157] and lenzoic 

 acid [Vol. II] by heating the glucoside 

 with benzoic anhydride (Schiff, Ann. 

 154, 5). 



