AGRICULTURAL CHEMISTRY — AGROTECHNY. 709 



Studies on anthocyans. — II-X, R. Wlllstattek et al, (Lichigs Ann, Chcm., 

 40s {1915), No. 1, pp. 1-162). — Continuing the investigation previously noted 

 (E. S. R., 31, p. 324), the following studies are reported: 



II. Coloring matter of the rose, by R. Willstatter and T. J. Nolan {pp. I-I4). — 

 The authors have found that cyanin, the anthocyan of the rose, is identical 

 with that of the cornflower. The varieties of color are dependent on the reac- 

 tion of the cell sap, whether acid, neutral, or alkaline. The white and yellow 

 rose contain practically no anthocyan, the rose-colored one a little, while the 

 dark red rose is rich in an acid-combined coloring matter, the alkali salt of 

 which determines the color of the cornflower. The identity of the anthocyans 

 was demonstrated by the ultimate chemical analysis and by their physical 

 properties. The preparation of cyanidin (CisHuOoCl) and its pseudobase 

 (C15H12O7.H2O) further established their identity. 



III. Coloring matter of the red xchortleherry, R. V,Hlstdtter and H. Mallison 

 {pp. 15--'fl). — Idaein was found to contain the same coloring component, cyani- 

 din, as the rose and cornflower, combined with one molecule of galactose. The 

 coloring matter was extracted from the berries by glacial acetic acid and subse- 

 quent precipitation from the extract with ether. It was further purified by 

 isolation as the picrate, from which the chlorid was obtained by treatment with 

 methyl-alcohol hydrochloric acid. This method was adopted; as one of the 

 common procedures . in the isolation of the anthocyans. On hydrolysis with 

 hydrochloric acid idaein yielded cyanidin chlorid and galactose. The cyanidin, 

 on heating with alkali, decomposed and yielded phloroglucinol and ortho 

 dihydroxy-benzoic acid. 



IV. Coloring matter of the scarlet pelargonium, R. Willstatter and E. K. 

 Bolton {pp. .'{2-61). — Scarlet pelargonium was found to contain but one coloring 

 substance, pelargonin, which is a diglucosid. On treatment with hydrochloric 

 acid it yielded glucose and the dye-component, pelargonidin, which is analogous 

 to cyanidin. A sulphate, nitrate, and oxalate of pelargonin were obtained, but 

 the picrate could not be isolated. On treatment with alkali, pelargonidin 

 chlorid yielded phloroglucinol and para-oxy-benzoic acid with a trace of proto- 

 catechuic acid. 



V. The anthocyan of the larkspur, R. Willstatter and W. Mieg {pp. 61-82). — 

 Delphinin, the coloring matter of the larkspur, was isolated either in the free 

 state or as the chlorid. On hydrolysis with hydrochloric acid the delphinin 

 chlorid yielded 2 molecules of glucose, 2 molecules of para-oxy-benzoic acid, 

 and 1 molecule of delphinidin chlorid. This anthocyanidin, on heating with 

 75 per cent alkali, decomposed Into phloroglucinol and probably gallic acid 

 which, at the temperature of the reaction, loses carbon dioxid and yields 

 pyrogallol. 



VI. Coloring matter of the grape and the ichortleherry, R. Willstatter and 

 E. H. Zollinger {pp. 83-100). — Enin, the anthocyan of the grape, was obtained by 

 the usual procedure, and purified by isolating as the picrate. Alcohol or alco- 

 holic hydrochloric acid could also be used as extraction agents. From the 

 picrate the enin chlorid was separated as red or brownish-red crystals. The 

 enin is a monoglucosid and, on hydrolysis, yields 1 molecule of glucose and 1 

 molecule of enidin chlorid. Heated with hydriodic acid the enidin chlorid 

 loses two methyl groups and yields delphinidin. Decomposed with alkali it 

 gives phloroglucinol and a methyl ester of gallic acid. 



Myrtillin was obtained from the whortleberry by alcoholic-hydrochloric acid 

 extraction, and purified by isolation as the picrate or chlorid. On hydrolysis 

 with hydrochloric acid it yielded myrtillidin chlorid in dark-brown pointed 

 prisms. 



