21890-57-3Relevant academic research and scientific papers
NAPHTHOQUINONES FROM DIONAEA MUSCIPULA
Kreher, Bernhard,Neszmelyi, Andras,Wagner, Hildebert
, p. 605 - 606 (1990)
Beside the known naphthoquinone, plumbagin, the new compound hydroplumbagin 4-O-β-glucopyranoside has been isolated from a methanolic extract of Dionaea muscipula, together with two known naphthoquinones, droserone and 3-chloroplumbagin which have not been reported previously from this plant.Structure determination of hydroplumbagin 4-O-glucoside was carried out unambiguously by NOE experiments.
Synthesis of some plumbagin derivatives and their antibacterial activity
Vasanth, Saradha,Balakrishna,George,Veluchamy
, p. 509 - 510 (2007/10/03)
Several plumbagin derivatives were synthesized from plumbagin and tested for their antimicrobial activity.
Preparation of naphthoquinone derivatives from plumbagin and their ichthyotoxicity
Ogihara, Kazuhito,Yamashiro, Rieko,Higa, Matsutake,Yogi, Seiichi
, p. 437 - 445 (2007/10/03)
Various naphthoquinone derivatives were prepared from a natural product, 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin); these were mostly substituted at C-3 through carbon-carbon bond formation mediated by a metal- based oxidant such as lead tetraacetate in the presence of various carboxylic acids. The halogenated compounds showed stronger ichthyotoxicity than plumbagin, but other derivatives were less active.
Method for dyeing keratinous fibres using a monohydroxyindole or dihydroxyindole and a non-oxidizing aromatic carbonyl derivative and dyeing agent
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, (2008/06/13)
The present invention relates to a method for dyeing keratinous fibers, characterized in that the following are applied to the fibers: a) a composition (A) containing, in a medium appropriate for dyeing, at least one monohydroxyindole or dihydroxyindole, this application being preceded or followed by the application of b) a composition (B) containing, in a medium appropriate for dyeing, at least one aromatic carbonyl derivative chosen from hydroxyacetophenones, hydroxybenzophenones, 2-hydroxy-1,4-benzoquinones, hydroxy-1,4-naphthoquinones,amino-1,4-naphthoquinones,hydroxy-9,10-anthraquinones and amino-9,10-anthraquinones. It also relates to the dyeing agents for carrying it out.
1,4-Naphthoquinones. XXIII: 2/3-Halogeno-2/3-nitrophenyl-juglone derivatives, synthesis and cytotoxic properties
Wurm,Gurka
, p. 627 - 630 (2007/10/02)
Radical arylation of 1,4-naphthoquinones is possible by oxidative decarboxylation of 2- and 4-nitrobenzoic acid. With 2- and 3-halogenojuglone derivatives the 4-nitrophenyl compounds 10-13 are prepared in good, the 2-nitrophenyl analogues 14-17 only in poor yields. - All compounds are inactive against the virus types HSV and HIV and their marked cytotoxicity in part depends on the substitution pattern. The 3-aryl and o-nitro derivatives are more active than their 2-aryl and p-nitro analogues and the influence of the chloro or bromo substitution is only remarkable in the case of 12/13.
1,4-Naphthoquinones, VII: C-Methylation of 1,4-Naphthoquinones
Wurm, Gotthard,Geres, Uwe
, p. 606 - 609 (2007/10/02)
The action of Fenton's reagent on dimethyl sulfoxide results in carbon methylation of the quinoid system of 1,4-naphthoquinones by .CH3 under particularly mild conditions.The results depend on the substitution pattern at positions 2 and 3 and on the suitable protection of the OH group at position 5.

