Über Methoxy-glaukobiline, einen neuen Typ bilirubinoider Farbstoffe, gleichzeitig ein Beitrag zur Kenntnis der Gmelinschen Reaktion. Mit 4 Figuren auf Tafel I
Ferrobilin (C33H35O6N4FeCL4) was prepared by suspending 1 g. bilirubin in 50 cc. glacial acetic acid, adding 1 g. of quinone, and heating the mixture. After filtering, the blue-green filtrate was conc. in vacuo, the crystals obtained dissolved in glacial acetic acid and FeCl3 added. The ferrobilin crystallized in green rosettes. Biliverdin dimethyl ester (C35H38O6N4, m. 213[degree]) was prepared by dissolving the ferrobilin in NaOH soln., filtering and acidifying the filtrate. The precipitate formed was dissolved in CHCl3 and treated with diazomethane in CHCl3. The biliverdin dimethyl ester crystallized in oblique truncated blue prisms. The ferrobilin dimethyl ester (C35H39O6N4FeCl4, m. 257[degree]) was obtained by treating the biliverdin dimethyl ester with FeCl3 in acetic acid. The 1[image]8[image]-dihydroxy-l,3,6,8-tetramethyl-7-ethyl-2-vinyl-bili-2[image], a,4[image]-ms-triene-4,5-dipropionic acid methyl ester (C35H40O6N4, m. 225[degree]) was formed by the condensation of formylneoxanthobilirubinic acid with vinyl-neoxanthobilirubinic acid by heating in the presence of HBr and MeOH. The ferrobilin of this condensation product was also prepared. Among other compounds prepared were: the ferrobilin of l[image],8[image]-dihydroxy-l,3,6,7-tetramethyl-8-ethyl-2-vinylbili-2[image], o,4[image]-ms-triene-4,5-dipropionic acid methyl ester and its Zn complex salt, 1[image],12[image]-dihydroxy-1,3,6,7,10, 12-hexamethyl-2,ll-divinylhexapyrrene-4,5,8,9-tetrapropionic acid methyl ester, the Zn complex salt of glaucobilin IX, a-dimethyl ester, and 1,6[image],-dihydroxy-2,3,6-trimethyl-l,5-diethyltripyrrene-4-propionic acid methyl ester.