Stilbene prenylated

Hakim, E.H. et al., Artoindonesianins N and O, new prenylated stilbene and prenylated aryl-benzofuran derivatives from Artocarpus gomezianus, Fitoterapia, 13, 597, 2002. 

The phenolics include anthocyanins, anthraquinones, benzofurans, chromones, chromenes, coumarins, flavonoids, isoflavonoids, lignans, phenolic acids, phenylpropanoids, quinones, stilbenes and xanthones. Some phenolics can be very complex in structure through additional substitution or polymerization of simpler entities. Thus xanthones can be prenylated and flavonoids, lignans and other phenolics can be glycosylated. Condensed tannins involve the polymerization of procyaninidin or prodelphinidin monomers and hydrolysable tannins involve gallic acid residues esterified with monosaccharides. As detailed in this review, representatives of some major classes of plant-derived phenolics are potent protein kinase inhibitors. 

Group B prenylated and geranylated stilbenes, regardless of the substitution position and including the cyclized derivatives. 

Group D carbon substituted stilbenes other than the prenylated and geranylated ones, the C-glycosides and those in group C. 

The Artocarpus species seem likely to produce prenylated stilbenes [44-46,48]. The root bark of Lonchocarpus chiricanus also yielded five new prenylated stilbenes, named chiricanines A-E (73-77) [49]. In this group. 

Except the prenylated stilbene artoindonesianin N (65), Artocarpus gomezianus Wall, ex Tree. (Moraceae) also yielded a new prenylated... 

Mulberroside F (104) showed moderate inhibitory effects on tyrosinase activity and on the melanin formation of melan-a cells. It also exhibited superoxide scavenging activity that is involved in the protection against auto-oxidation [62]. The geranylated stilbenes 81 and chlorophorin from Chlorophora excelsa [51], prenylated ones 4-prenyloxyresveratrol and artocarbene (72) from Artocarpus incisus [528] all demonstrated tyrosinase inhibitory activity (ICso 96, 1.3, 0.66 and 2.45 //M, respectively). 

The prenylflavanones with either prenyl-, lavandulyl-, or geranyl groups on the A ring, two bioactive flavonostilbenes on the ringB, and stilbene... 

Arylbenzofuran-ketalized Diels-Alder adducts include (1-3 ,11-5)-dihydrochalcone-prenyl-2-arylbenzofuran dimers (422-426) a (l-a,ll-3 1-P,Il-6 )-dihydrochalcone-prenyl-2-aiylbenzofuran dimer, a Diels-Alder adduct of a dehydroprenyl-2-aiylbenzofuran with a chalcone (427) a (l-a,ll-3 1-P,ll-6 )-dihydrochalcone-prenyl-2-aiylbenzofuran dimer (428) a 2-arylbenzofuran-prenyldihydrochalcone dimer (429) 2-arylbenzofuran-ketalized Diels-Alder adducts (430-431) Diels-Alder-type adducts of a chalcone and a dehydroprenylstilbene (432-433) and stilbene and diprenyldihydrochalcone dimers (434-438). 

H (II), I (III), and J(IV) has been achieved through a flexible and expedient strategy that features a cascade sequence involving two concurrent [3,3] sigmat-opic rearrangements and an unusual intramolecular formal [2 + 2] thermal cycloaddition reaction between an electron-rich stilbene and a prenyl group [109]. 

Prenyl substitution is a conventional derivatization style in stilbenes, exemplified by artoindonesianin N 29 immArtocarpus gomezianus [17]. The prenyl groups in stilbenes cyclize to form new derivatives. 4-Hydroxy-5 -methoxy-6",6"-dimethylpyran[2",3" 3, 4 ]stilbene 30, 3,5 -dimethoxy-4-hydroxy-6",6"-dimethylpyran[2",3" 3, 4 ]stilbene 31, and 3,4,5-trimethoxy-6",6"-dimethylpyran [2",3" 3, 4 ]stilbene 32, with dimethylchromene ring in their structures, have been obtained from Lonchocarpus utilis (Leguminosae) [18]. Furthermore, schweinfurthins A-C 33-35 from the leaves of Macaranga schweinfurthii (Euphorbiaceae) are typical samples of the prenylated stilbenes [19]. 

The bibenzyls are characterized by the presence of one 1,2-diphenylethane structure in their molecules. Similar with the stilbene structures, there are hydroxyls, methyl, methoxy, prenyl, geranyl, etc., located in the structures of bibenzyls. Bibenzyls have been mainly isolated from bryophytes. In addition, a few compounds of this group were reported from the genera of Stemona, Dendrobium, and Polygonum. 

Stilbenoids represent a group of important natural products in the plant kingdom. The developments of modem analytical methods accelerate the discovery of these compounds, and to this day more than 1,000 stilbenoids have been isolated. For the stilbenes, bibenzyls, and phenanthrenes, these three groups shared the feature of their nucleus with hydroxyls, methyl, methoxy, prenyl, geranyl, glycosyl, etc., substituents. The oligostilbenes and bisbibenzyls are formed by polymerization of stilbene and bibenzyl units, and the diverse polymerized patterns produced their... 

Yoder BJ, Cao S, Norris A, Miller JS, Ratovoson F, Razafitsalama J, riantsiferana R, Rasamison VE, Kingston DGI (2007) Antiproliferative prenylated stilbenes and flavonoids from Macaranga alnifolia from the Madagascar rainforest. J Nat Prod 70 342-346... 

Chlorophorin is a prenylated tetrahydroxystilbene of the West African hardwood iroko (Chlorophora excelsa) (72). This wood is durable and resembles teak or oak. It is used for both outdoor and indoor constructions. The wood cannot be varnished or surface treated with lacquer since the chlorophorin, like many other 2- and 4-hydroxysubstituted stilbenes, prevents proper hardening of the polyester. Workers exposed to saw dust of iroko wood develop strong allergic reactions that have been ascribed to the chlorophorin content of the wood (56) (see also Chap. 9.5). 

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