New Isoflavones and Pterocarpane with Hepatoprotective Activity from the Stems of Erycibe expansa

Abstract

The methanolic extract from the stems of Erycibe expansa was found to show a hepatoprotective effect on D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes. By bioassay-guided separation, two new prenylisoflavones and a pterocarpane, erycibenins A (1), B (2), and C (3), were isolated from the active fraction (the EtOAc-soluble fraction) together with ten isoflavones (4 - 13) and seven pterocarpanes (14 - 20). The stereostructures of the new compounds were determined on the basis of chemical and physicochemical evidence including modified Mosher’s method. In addition, the isolated constituents, erycibenin A (1, IC₅₀ = 79 μM), genistein (6, 29 μM), orobol (7, 36 μM), and 5,7,4′-trihydroxy-3′-methoxyisoflavone (8, 55 μM) exhibited inhibitory activity on D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes.

Key words

Erycibe expansa - Convolvulaceae - erycibenin - isoflavone - pterocarpane - hepatoprotective effect

References

• 1 Yoshikawa M, Morikawa T, Nakano K, Pongpiriyadacha Y, Murakami T, Matsuda H. Characterization of new sweet triterpene saponins from Albizia myriophylla .  J Nat Prod. 2002;  65 1638-42
• 2 Matsuda H, Pongpiriyadacha Y, Morikawa T, Ochi M, Yoshikawa M. Gastroprotective effects of phenylpropanoids from the rhizomes of Alpinia galanga in rats: structural requirements and mode of action.  Eur J Pharmacol. 2003;  471 59-67
• 3 Morikawa T, Kishi A, Pongpiriyadacha Y, Matsuda H, Yoshikawa M. Structures of new friedelane-type triterpenes and eudesmane-type sesquiterpene and aldose reductase inhibitors from Salacoa chinensis .  J Nat Prod. 2003;  66 1191-6
• 4 Morikawa T, Matsuda H, Yamaguchi I, Pongpiriyadacha Y, Yoshikawa M. New amides and gastroprotective constituents from the fruit of Piper chaba .  Planta Medica. 2004;  70 152-9
• 5 Yahara S, Ogata T, Saijo R, Konishi R, Yamahara J, Miyahara K, Nohara T. Isoflavan and related compounds from Dalbergia odorefera. I.  Chem Pharm Bull. 1989;  37 979-87
• 6 Kobayashi M, Noguchi H, Sankawa U. Formation of chalcones and isoflavones by callus culture of Glycyrrhiza uralensis with different production patterns.  Chem Pharm Bull. 1985;  33 3811-6
• 7 Hosny M, Rosazza J PN. Microbial hydroxylation and methylation of genistein by Streptomycetes .  J Nat Prod. 1999;  62 1609-12
• 8 Heerden F R, Brandt E V, Roux D G. Synthesis of the pyranoisoflavonoid, heminitidulan. isoflavanoid and rotenoid glycosides from the bark of Dalbergia nitidula Welw. ex Bak. J Chem Soc Perkin Trans I 1980: 2463-9
• 9 Fourie T G, Ferreira D, Roux D G. Flavonoid synthesis based on photolysis of flavan-3-ols, 3-hydroxyflavanones, and 2-benzylbenzofuranones. J Chem Soc Perkin Trans I 1977: 125-33
• 10 Chan S C, Chang Y S, Wang J P, Chen S C, Kuo S C. Three new flavonoids and antiallergic, anti-inflammatory constituents from the heartwood of Dalbergia odorifera .  Planta Medica. 1998;  64 153-8
• 11 Kinoshita T, Ichinose K, Takahashi C, Ho F C, Wu J B, Sankawa U. Chemical studies on Sophora tomentosa: the isolation of a new class of isoflavonoid.  Chem Pharm Bull. 1990;  38 2756-9
• 12 Jackson B, Owen P J, Scheinmann F. Extractives from poisonous British plants. part I. the structure of alpinumisoflavone, a new pyranoisoflavone from Laburnum alpinum J. Presl. J Chem Soc (C) 1971: 3389-92
• 13 Chibber S S, Sharma R P. Derrone, a new pyranoisoflavone from Derris robusta seeds.  Phytochemistry. 1980;  19 1857-8
• 14 Ozaki Y, Mochida K, Kim S W. Aromatic annelation with α-phenylsulfinyl-γ-butyrolactones, a novel route to 4-(2-hydroxyalkyl)-1,3-benzenediols.  Chem Pharm Bull. 1987;  35 1790-5
• 15 Pelter A, Ward R S, Gray T I. The carbon-13 nuclear magnatic resonance spectra of flavonoids and related compounds. J Chem Soc Perkin Trans I 1976: 2475-83
• 16 Tanaka T, Ohyama M, Iinuma M, Shirataki Y, Komatsu M, Burandt C L. Isoflavonoids from Sophora secundiflora, S. arizonica and S. gypsophila .  Phytochemistry. 1998;  48 1187-93
• 17 Barrero A F, Cabrera E, Garcia I R. Pterocarpanes from Ononis viscosa Subsp. breviflora .  Phytochemistry. 1998;  48 187-90
• 18 Xu F, Morikawa T, Matsuda H, Ninomiya K, Yoshikawa M. Structures of new sesquiterpenes and hepatoprotective constituents from Egyptian herbal medicine Cyperus longus .  J Nat Prod. 2004;  67 569-76
• 19 Ohtani I, Kusumi T, Kashman Y, Kakisawa H. High-field FT NMR application of Mosher's method. the absolute configurations of marine terpenoids.  J Am Chem Soc. 1991;  113 4092-6
• 20 Kitagawa I, Chen W Z, Hori K, Harada E, Yasuda N, Yoshikawa M, Ren J. Chemical studies of Chinese licorice-roots. I. elucidation of five new flavonoid constituents from the roots of Glycyrrhiza glabra L. collected in Xinjiang.  Chem Pharm Bull. 1994;  42 1056-62