[Agr. Biol. Chem., Vol. 34, No. 6, p. 900•`907, 1970] Isolation and Structure of New Flavonoids, Flavoyadorinin-A. Flavoyadorinin-B and Homo-flavoyadorinin-B, in the Leaves of Viscum album Linnaeus var. coloratura Ohwi Epiphyting to Pyrus communis Linnaeus_??_ By Naokazu OHTA and Kazuyoshi YAGISHITA Department of Food Chemistry, Kumamoto Women'sUniversity, Ooemachi, Kumamoto City, Japan Received November 10, 1969 The flavonoid constituents of the leaves of Viscum album Linnaeus var. coloratum Ohwi (Viscaceae) epiphyting to Pyrus communis Linnaeus were examined. Three kinds of new flavonoids named Flavoyadorinin-A (I), C23H24O12, mp245•`246•Ž, Flavoyadorinin-B (II), C23H24O11•E3H2O, mp 203•`206•Ž, and Homo-flavoyadorinin-B (III), C28H32O15•E3H2O, mp 208•`210•Ž (sint. at 130•Ž) were isolated from the leaves of this plant. The structures of the Compound (I), (II), and (III) were showed to be 7,3'-di-O-methyl- quercetin-3-O-mono-D-glucoside (rhamnazin-3-0-mono-D-glucoside), 7,3'di-O-methyl-luteolin- 4'-O-mono-D-glucoside, and 7,3'-di-O-methyl-luteolin-4'-O-D-glucoapioside, respectively. Japanese mistletoe, Viscum album Linnaeus mistletoe (Viscum album Linnaeus var. coloratum var. coloratum Ohwi is a perennial shrub of Ohwi) epiphyting to Pyrus communis Linnaeus. Viscaceae, which grows wild in Saghalien, As described in the experimental part, Kurles, Honshu, Shikoku, Kyushu, Formosa, three flavonoids were isolated in pure state Korea and China. on a cellulose-column chromatography, Com- In 1957, the isolation of four kinds of pound (I), mp 245•`246•Ž, Compound (II), flavonoids, Compound A, mp208•`210•Ž mp203•`206•Ž, and Compound (III), mp (positive Molish reaction), Compound B, mp 208210°C. All of these compounds, (I), 107•`109•Ž, Compound C, mp 142•`143•Ž, (II) and (III), were new flavonoids, which and Compound D, mp219•`220•Ž (all were would be named Flavoyadorinin-A Flavo positive to Mg-HCl reaction) were reported yadorinin-B, and Homo-flavoyadorinin-B, re by Ts'eng Kuang-Fang et al .1) No further spectively. investigations of their structures, however, The compound (I), named flavoyadorinin-A, have been made. was obtained as pale yellowish needles, mp The present paper deals with the isolation 245246°C, and from its analytical values and the structural elucidation of flavonoid was suggested the formula C23H24O12 contain compounds in the fresh leaves of Japanese ing two methoxyl groups. It exhibited a dark green color with ferric chloride, and _??_A part of this work was presented at the General the reduction tests for flavonoid (Mg-HCl, Meeting of the West Japan Branch of the Agricultural Zn-HCl) were positive. It also was positive Chemical Society of Japan, held on October 20, 1968, at the Shimane University, Japan. in the Gibbs indophenol test. The UV- 1) Ts'eng Kuang-Fang and Li Shil-Chuen , Yao spectrum of this compound (I), maxima Hsueh Hsueh Pao (Acad. Sinica), 5, 169 (1957). 253.4, 268, and 350 mfg, and its pattern, Isolation and Structure of New Flavonoids, Flavoyadorinin-A, Flavoyadorinin-B 901 were very similar to those reported for a (Mg-HCl, Zn-HCl) were positive. It was also number of flavonoids of the quercetin type. positive in the Gibbs test. The UV-spectrum This was also supported by the fact that of this compound (II), maxima 2436, 2712, demethylation of the compound (I) with and 334•`6mƒÊ, and its pattern, were very hydriodic acid in phenol gave quercetin, mp similar to those reported for a number of 314•`317•Ž, which was further characterized flavonoids of the luteolin type. This also as its penta-acetate (mp201•Ž). was supported by the fact that demethylation On the hydrolysis with 30o sulfuric acid, of the compound (II) with hydriodic acid in the compound (I) gave an aglycon (IV) as pale phenol gave luteolin, mp 326•`329•Ž. Its yellowish needles (mp 2l0•`216•Ž, 66.79%), acetate, mp 226•`227•Ž. which was identical with the authentic On the hydrolysis with 3% sulfuric acid specimen of rhamnazin (7,3'-di-O-methyl- the compound (II) gave a new aglycon (V) as quercetin)* obtained from the leaves of Poly yellowish granular crystals (58.51%), C15H8O4•E gonum hydropiper Linnaeus. From the hy (OCH3)2, mp 218•`220•Ž, which would be drolyzate freed of the aglycon (IV), D-glucose named flavoyadorigenin-B, hereafter. Acetate was proved to be present by paper chro of this aglycon (V), mp 182•`186•Ž. In the matography. Alkali fusion of the compound hydrolyzate freed of the aglycon (V), only (I) under the usual manner gave mono-O- D-glucose was detected as the sugar component methyl-phloroglucinol and vanillic acid. The by paper chromatography. Alkali fusion of compound (I) and its aglycon (IV) were the compound (II) under the usual manner confirmed by comparing their UV-spectra gave mono-O-methyl phloroglucinol, and with those in presence of the following vanillic acid. In the UV-absorption deter reagents:" 1) sodium acetate (both the com- mination, the following results were con pound (I) and its aglycon (IV):-no change); firmed: 1) both the compound (II) and its 2) aluminum chloride (the compound (I):-no aglycon (V) showed no shift of the absorption change, its aglycon (IV):-the bathochromic maximum by adding sodium acetate, suggest- shift of 59 mg); and 3) sodium ethylate (the ing the presence of 7-methoxyl group, and compound (I):-the long wavelength bands also showed a significant bathochromic shift disappearing, its aglycon (IV):-the batho (about 10mƒÊ) by adding aluminum chloride, chromic shift of 57 mp). indicating the presence of 5-hydroxyl group On the basis of these data the structure of in their nucleus; 2) the aglycon (V) showed the compound (I) might be rhamnazin-3-O- a characteristic bathochromic shift (70mƒÊ) of mono-D-glucoside. absorption maximum by adding sodium The compound (II), named flavoyadorinin- ethylate, suggesting the presence of 4'- B, was obtained as yellowish needles, mp hydroxyl group in its structure. 203-206°C, and from its analytical values From these results the structure of the was suggested the formula C21H18O9(OCH3)2•E compound (II) and its aglycon (V) might be 3H2O. It gave brown color with ferric chlo 7,3'-di-O-methyl-luteolin-4'-O-mono-D-glucoside ride, and the reduction tests for flavonoid and 7,3'-di-O-methyl-luteolin, respectively. The compound (III), named homo-flavo * The authentic sample of rhamnazin was fur yadorinin-B, was obtained as yellowish needles, nished through the courtesys of Dr. M. Aritomi mp 208•`210•Ž (sint. at 130•Ž), and analyzed (Kumamoto University) and Dr. A. Kawase (Hiroshima for C26H26O13(OCH3)2•E3H2O. It gave brown Women's University). color with ferric chloride, and the reduction 2) L. Jurd, "The Chemistry of Flavonoid Com- tests for flavonoids were positive. Gibbs: pounds," ed. by T. A. Geissman, Pergamon Press, 1962, p. 107. positive. The UV-spectrum of the compound 902 N. OHTA and K. YAGISHITA (azaleatin) E. Wada, J. Am. Chem. Soc., 78, 4725 (1956). (rhamnetin) A. G. Perkin and J. R. Allison, J. Chem. S oc., 81, 468 (1902). (isorhamnetin) R. Chatterjee and D. K. Datt, Indian J. Physiol., 4, 61 (1950). (tamarixetin) A. G. Perkin and P. J. Wood, J. Chem. Soc., 73, 374 (1898). (rhamnazin) A. G. Perkin and J. Geldard, ibid., 67, 496 (1895). (ombuin) G. B. Marini-Bettolo, V. Deulofeu and E. Hug, Gazz. chim. ital., 80, 63 (1950). (ayanin) F. E. King, T.J. King and K. Sellars, J. C mem. Soc., 1952, 92. (diosmetin) E. Vongerichten, Ber., 33, 2334 (1900). (chrysoeriol) F. B. Power and F. Tutin, Proc. Am. Pharm. Assoc., 54, 352 (1906). (III), maxima 243---6, 271- 2, and 340 mp, and Rf value with that of D-glucose and the other its pattern, were almost the same as that of was also proved to be apiose, by cochromato the compound (II), suggesting a close simi graphy on paper using the sugar solution larity in the structure between the compound obtained from the hydrolyzate of authentic (II) and the compound (III). This was also apiin.* Moreover, partial hydrolysis of the proved by the fact that the compound (III) compound (III) with 5% acetic acid gave the with hydriodic acid in phenol in the same compound (II) and apiose. manner as before gave luteolin, mp 326 The compound (III) was also confirmed by •` 329•Ž. comparing its UV-spectrum with those in On the hydrolysis with sulfuric acid in the presence of the following reagents: 1) sodium usual manner, the compound (III) produced acetate (no change), 2) aluminum chloride an aglycon as yellowish granular crystals (the bathochromic shift of about 10 mp), 3) (50.1%), C15H8O4(OCH3)2 mp 218•`220•Ž, sodium ethylate (the long wavelength bands which was proved to be identical with the disappearring). compound (V), by mixed mp and IR-absorp Consequently, the structure of the com- tion data. In the hydrolyzate freed of the aglycon (V), two kinds of sugar components * The authentic specimen of apiin was furnished were proved to be present by paper chro through the courtesy of Dr. A. Kawase (Hiroshima matography. One of these was identical in Women's University). Isolation and Structure of New Flavonoids, Flavoyadorinin-A, Flavoyadorinin-B 903 pound (III) might be 7,3'-di-O-methyl-luteolin- that flavonoid compounds in the leaves of 4'-O-D-glucoapioside. Viscum album Linnaeus var. coloratura Ohwi In this way, it has now become evident epiphyting to Pyrus communis Linnaeus consist of three kinds of 7,3'-di-O-methyl flavonoids, i.e., flavoyadorinin-A (I), flavoyadorinin-B (II), and homo-flavoyadorinin-B (III).