Chemical investigation of many bacterial and fungal, as well as plant species has revealed the presence of in- teresting compounds derived from naphthalene - 1,4-naphthoquinones and rarely also 1,2-naphthoquinones. They were detected in many species of families Bignoniaceae, Droseraceae, Plumbaginace, Boraginaceae, Juglandaceae as well as in species of small families, such as Dioncophyllaceae or Acanthaceae. Naphthoquinones have very interesting spectrum of biological actions, including antibiotic, antiviral, anti-inflammatory, antipyretic, antiproliferative and cytotoxic effects. Because of these properties the plants containing them are used in folk medicines, mainly by natives in Asia, where espe- cially Chinese medicine uses aerial as well as subterranean parts of these plants for hundreds years, and South America. The utilizing of naphthoquinones for medicinal purposes and their occurrence in nature is reviewed and discussed. Moreover, we review analytical techniques using for their analysis.

Noteworthy Secondary Metabolites Naphthoquinones – their Occurrence, Pharmacological Properties and Analysis

This review article describes research on cytotoxic natural products isolated from plant sources, primarily preclinical lead identification and structural modification studies performed in the Natural Products Laboratory of Dr. K. H. Lee. As a result of this work, more than 100 new cytotoxic antitumor compounds and their synthetic analogs have shown confirmed activity in NCI's in vitro human tumor cell lines bioassay and are of current interest to NCI for further in vivo evaluation. A significant and ongoing project involves novel antitumor analogs related to podophyllotoxin and etoposide, and has led to a potent derivative designated GL331 (17). This compound is currently in Phase IIa clinical trials and shows promise as an anticancer drug, especially for drug-resistant cancers. Bioactivity-directed fractionation and isolation of medicinal herbs (primarily herbs of Chinese origin) have also led to many classes of cytotoxic compounds including polyphenolic compounds, sesquiterpene lactones, lignans, quassinoids, triterpene glucosides, flavonoids, colchicine derivatives, and quinone derivatives. © 1999 John Wiley & Sons, Inc. Med Res Rev, 19, No. 6, 569–596, 1999

Novel antitumor agents from higher plants.

The distribution of the chemical compounds iridoids, anthraquinones, and verbascosides is demonstrated in Dahlgrenograms. An analysis of iridoid biosynthesis and structure allows distinction of two main groups of compounds. Thus, the biosynthetic route I gives rise to the seco-iridoids and their derivatives, and another (route II) to aucubin and similar decarboxylated iridoid glucosides. Seco-iridoids from route I are widely distributed in Cornanae, Loasanae, and Gentiananae but never in Lamianae. Aucubinlike compounds derived by route II are commonly found in Lamianae and in three small families in Cornanae, but are not found in Gentiananae (...)

Systematic implications of the distribution of iridoids and other chemical compounds in the Loganiaceae and the other families of the Asteridae

The Constituents from the Stems of Annona cherimola

Saetung, A., Itharat, A., Dechsukum, C., Keawpradub, K., Wattanapiromsakul, C., and Ratanasuwan, P. Cytotoxic activity of Thai medicinal plants for cancer treatment Songklanakarin J. Sci. Technol., 2005, 27(Suppl. 2) : 469-478 Twelve Thai medicinal plants as the ingredients of a Southern Thai traditional formula for cancer treatment were selected to test cytotoxicity activity against two types of human cancer cell lines ; large cell lung carcinoma (CORL-23) and prostate cancer cell lines (PC3) and one type of normal human cell line, fibroblast cells (10FS). SRB assay was used to test cytotoxic activity against all the cell types. Two of the extracts (water and ethanolic extracts) procedures used were similar to those practised by Thai traditional doctors. One concentration (50 μg/ml) of two different extracts was tested first against cell lines and the active plant extracts were diluted and tested for calculating IC50. The ethanolic extracts of six plants (Bridelia ovata, Curcuma zedoaria, Derris scandens, Dioscorea membranacea, Nardostachys jatamansi and Rhinacanthus nasutus) showed cytotoxic activity (IC50< 30 μg/ml) against lung and prostate cancer cell lines. Dioscorea membranacea roots showed the highest cytotoxic activity against lung cancer cell lines ( IC50= 4.6 μg/ml) but it exhibited low cytotoxic activity against prostate cancer cell lines (IC50= 17.55 μg/ml) and less cytotoxic activity against normal cell lines (IC50= 66.05 μg/ml). Curcuma zedoaria showed cytotoxic activity against COR L-23 and PC3 but less cytotoxic activity against 10FS (IC50 = 6.05, 17.84 and 55.50 μg/ml respectively) Rhinacanthus nasutus root extract showed the highest cytotoxic activity against PC3 ( IC50 = 2.01 μg/ml) and this extract also showed high activity against COR L-23 and 10FS (IC50=5.05 and 10.95 μg/ml respectively). The water extract 1Graduate student in Pharmacognosy, 2Ph.D. (Pharmacognosy), Assoc. Prof., 4Ph.D. (Phytochemistry), 5Ph.D. (Pharmacognosy), Asst. Prof, 6B.Sc. (Biology), Scientist, Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, 3Ph.D. (Pathology), Department of Pathology, Faculty of Medicine, Prince of Songkhla University, Hat Yai, Songkhla 90112, Thailand. Corresponding e-mail: arunporn.i@psu.ac.th Received, 12 August 2004 Accepted, 17 November 2004 ORIGINAL ARTICLE Songklanakarin J. Sci. Technol. Vol. 27 (Suppl. 2), 2005 : Thai Herbs 470 Cytotoxicity activity of Thai medicinal plants

Cytotoxic activity of Thai medicinal plants for cancer treatment

Isolation and cytotoxicity of rhinacanthin-A and -B, two; naphthoquinones, from Rhinacanthus nasutus

Reinvestigation of the root of Rhinacanthus nasutus afforded, in addition to rhinacanthin-A to -D reported previously, two new dimethyldihydropyranonaphthoquinone esters (5, 6) and eight new 2-hydroxy-1,4-naphthoquinone esters (7-14) were isolated The stereochemistry of rhinacanthin-A was determined as the R configuration Compounds rhinacanthin-G to -N, belong to a class of 2-hydroxy-3-(3-hydroxy-2,2-dimethylpropyl)-1,4-naphthoquinone esters, and so far have been isolated only in this plant Their biosynthesis is also discussed

Naphthoquinone Esters from the Root of Rhinacanthus nasutus

Annoquinone-A, an antimicrobial and cytotoxic principle from Annona montana

Reinvestigation of the root of Rhinacanthus nasutus afforded, in addition to rhinacanthin-A to -D reported previously, two new dimethyldihydropyranonaphthoquinone esters (5, 6) and eight new 2-hydroxy-1,4-naphthoquinone esters (7-14) were isolated. The stereochemistry of rhinacanthin-A was determined as the R configuration. Compounds rhinacanthin-G to -N, belong to a class of 2-hydroxy-3-(3-hydroxy-2,2-dimethylpropyl)-1,4-naphthoquinone esters, and so far have been isolated only in this plant. Their biosynthesis is also discussed.

Hsien Ju Tien

Papers

Isolation and cytotoxicity of rhinacanthin-A and -B, two; naphthoquinones, from Rhinacanthus nasutus

Naphthoquinone Esters from the Root of Rhinacanthus nasutus

Annoquinone-A, an antimicrobial and cytotoxic principle from Annona montana

Naphthoquinone Esters from the Root of Rhinacanthus nasutus