Identification of Flavones by the Ultra-Violet Absorption Spectra of their Ions

The Distribution of Rutin and Other Flavonoid Substances in Buckwheat Seedlings.

“…In both ethanolic and alkaline solutions substances B and D display spectra very similar to those reported for some derivatives of apigenin (18) and C, on the other hland, show in ethanol the low peak or shelf in the region 290 to 310 m,u characteristic of flavonols (1,26), and the spectra of these two strongly resemble those reported by Briggs and Locker (6) for some substituted derivatives of quercetin. The stability of A, B, C, and D in alkaline solution suggests that none of these substances possess an ortho-diphenolic configuration.…”

“…These are depicted in figure 1 (A-E) with the logarithm of absorbance plotted against wavelength in order to remove the effect of concentration, which is unknown in all cases. Since measurements were made on the same eluates in both ethanolic and alkaline solutions, it is possible to compare in a relative way the heights of the absorption peaks under these conditions (18). A summary of spectral relations is presented in table II.…”

The biosynthesis of phenolic glucosides in plants

“…cell). Free phenolic hydroxyl groups were detected by a bathochromic shift in the presence of base (Mansfield, Swain & Nordstrom, 1953) and ene-diol groupings were revealed by a hypsochromic shift on subsequent addition of borate ions to the alkaline PHENOLIC GLUCOSIDES IN PLANTS solution (Swain, 1954). Infrared measurements were made with a Unicam SP.…”

FLAVONOIDAL COMPOUNDS OFINULA VISCOSAPART II

“…203-20S0 C. Analysis for C,,H,,O,,CJ5.23;H,4.60°/o found CJ4.65; H,4.57% UV spectrum of compound I showed the maxima at 353 nm (Bant I) and 254 nm (Bant 11), UV shifts with the following solvents suggested that C,-OH is not free, C,-OH group is free and an o-dihydroxy group is present. AICI, caused a bathochromic shift 273, 300sh, 313sh, 438 nm, AICI,I'HC1 255, 267sh, 298, 358 nm as given by GE~SSMAN (1962), NaOMe 260, 288, 408 nm as shown by MANSFIELD, SWAIN, NORDSTROM (1953), NaOAc 253, 26Ssh, 283, 353 nm as shown by JURD, HOROWITZ (1957), NaOAc-H,BOS 257, 288, 368 nm as given by JURD (1956).…”