Isoprenylated flavonoids

Chemistry and biosynthesis of isoprenylated flavonoids from moraceous plant 99PAC1116. 

Nomura T. The Chemistry and Biosynthesis of Isoprenylated Flavonoids From Moraceous Plants Pwre A/y)/. Chem. 1999 77 1115-1118... 

Cui L, Ndinteh DT, Na MK, Thuaong PT, Muruumu J, Silike, Njamen D, Mbafor JT, Fomnm ZT, Ahn JS. (2007) Isoprenylated flavonoids from the stem bark of Erythrina abyssinica. JNat Prod 70 1039-1042. 

Na MK, Jang JP, Njamen D, Mbafor JT, Fomum ZT, Kim BY, Oh WK, Ahn JS. (2006) Protein tyrosine phosphatase-IB inhibitory activity of isoprenylated flavonoids isolated from Erythrina mildbraedii. J Nat Prod 69 1572-1576. 

Fukai, T. et al.. Components of the root bark of Morus cathayana. 1. Structures of five new isoprenylated flavonoids, sanggenols A-E and a diprenyl-2-arylbenzofuran, mulberrofuran V, Heterocycles, 43, 425, 1996. 

Table 16.2 lists more than 80 examples of new isoprenylated chalcones reported in the period 1992 to 2003 (see also Figure 16.7). Almost half of the compounds described here are from the Leguminosae, a trend that is also evident in earlier surveys. Other plant families that are well represented in Table 16.2 are the Moraceae and the Cannabinaceae. The literature on isoprenylated flavonoids in general has been reviewed by Barron and Ibrahim to the end of 1994 57 jjjg phenolic constituents of Glycyrrhiza species (licorice), among which are many isoprenylated chalcones, were the subject of an extensive review that includes literature published up to the end of 1996. Nomura and Hano have reviewed the literature on isoprenylated phenolic compounds of the Moraceae to the end of 1993. More recent descriptions of isoprenylated flavonoids are available for the hop plant, Humulus lupulus (Cannabinaceae),and the Moraceae genera Artocarpus and Dorstenia. ... 

The biological activity of isoprenylated chalcones from the Moraceae has been described both in original papers and reviews. Of particular interest is the potent 5-a-reductase inhibition shown by a geranylated chalcone (84) isolated from leaves of Artocarpus incisus The inhibitory effect is decreased by a factor of 2 when the geranyl substituent is lacking, as in butein (2, 4, 3,4-tetrahydroxychalcone). Compound 41, which was obtained from the leaves of Madura tinctoria together with four known isoprenylated flavonoids, showed inhibitory... 

Asada, Y., Li, W., and Yoshikawa, T., Isoprenylated flavonoids from hairy root cultures of Glycyrrhiza glabra. Phytochemistry, 47, 389, 1998. 

Kyogoku, K. et al.. Anti-ulcer effect of isoprenyl flavonoids. II. Synthesis and anti-ulcer activity of new chalcones related to sophoradin, Chem. Pharm. Bull, 27, 2943, 1979. 

Nomura, T., The chemistry and biosynthesis of isoprenylated flavonoids from moraceous plants. Pure Appl Chem., 71, 1115, 1999. 

CHEMISTRY AND BIOLOGICAL ACTIVITIES OF ISOPRENYLATED FLAVONOIDS FROM MEDICINAL PLANTS (MORACEOUS PLANTS AND GLYCYRRHIZA SPECIES)... 

About seventy kinds of new phenolic compounds could be isolated from Japanese cultivated mulberry tree (Morus alba, M. bombycis, and M, Ihou) and Chinese crude drug Sang-Bai-Pi (the root bark of Chinese mulberry tree). Most of them are isoprenylated flavonoids. Among them, kuwanon G (1) was the first isolation of the active substance exhibiting the hypotensive effect from the Japanese Morus alba root bark [9]. Furthermore, kuwanon G (1) and its isoprenylated derivative kuwanon H (2) [10] are considered to be formed through an enzymatic Diels-Alder type reaction of a chalcone and a dehydrokuwanon C or its... 

Morusin (3), a flavone derivative, isolated from the root bark of Morus alba L., as a main isoprenylated flavonoid, has a structure bearing an isoprenoid moiety at the C-3 position and a 2, 4 -dioxygenated pattern in the B ring [15]. These features are one of the characteristics of the isoprenylated flavonoids of Morus root bark. 

A series of isoprenylated flavonoids has been isolated from the following moraceous plants Brosimopsis oblongifolia, a Brazilian plant [36], Chinese Cudrania tricuspidata [37], and Taiwanese and Chinese Cudrania cochinchinensis [38]. Many xanthones with one or two isoprenoid groups have also been isolated from these Cudrania species... 

II. HYPOTENSIVE ACTIVITY OF ISOPRENYLATED FLAVONOIDS FROM THE ROOT BARK OF MORUS SPECIES... 

While the other biochemical tests and the inhibition of tumor promotion of teleocidin in a two-stage carcinogenesis experiment have not been carried out, due to limitation in their amounts available, some of isoprenylated flavonoids from the moraceous plants showed the similar inhibitory potencies to those of morusin (3) and the related compounds, Figs. (6) and (12), as shown in Table 3. 

Table 3. Effects of the isoprenylated flavonoids on inhibition of specific [3H]TPA binding (IDjo, pmol/L)...

Since most P-gp effectors are hydrophobic, it was of interest to study flavonoids substituted with different hydrophobic groups, for example the isoprenyl group [210]. Isoprenylated flavonoids are natural compounds which constitute a class of plant secondary metabolites. Comte et al. [210] have synthesized a series of C- or O-substituted hydrophobic derivatives of chrysin (22). Increasing the hydrophobicity of substituents at positions 6, 7, or 8 increased the affinity of binding to the purified cytosolic domain of P-gp. Isoprenylated derivatives also increased intracellular daunomycin (78) accumulation in K562/R7 leukemic cells. 

Nomma, T. Hano, Y. Fukai, T., Chemistry and biosynthesis of isoprenylated flavonoids from Japanese mulberry tree, Proc. Jpn. Acad. Ser. B, Phys. Biol. Sci., 2009, 85, 391-408. 

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