Abstract: The present invention provides a method for easily and inexpensively preparing a racemate or an optically-active 2-(1 -hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione in high yields, 2-acetyl-2,3-dihydro-5-hydroxynaphtho[2,3-b]furan-4,9-dione which is useful as an intermediate for preparing NFD, and an anticancer agent comprising 2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione as an active ingredient. Said 2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione is obtained in 4 or 5 steps by using comparatively inexpensive 5 -hydroxynaphthalene-1,4-dione (also referred to as juglone) as a starting material.

Abstract: One of the problems to be resolved by the present invention is to stably and sustainably produce active ingredients contained in Bignoniaceous plants of which a mass production is difficult in a conventional manner. The present invention relates to a method for efficiently preparing an anticancer active ingredient NQ801 by a cell cultivation of Bignoniaceous plants under specific culture conditions. An ingredient-production system in the present invention has an anticancer activity.

Abstract: An object of the present invention is to provide a method for efficiently preparing (S)-2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]-furan-4,9-dione useful as a medicine at a low cost and in large amounts. According to the present invention, the desired (S)-2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione can be prepared with high efficiency at a low cost and in large amounts by asymmetrically reducing 2-acetyl-5-hydroxynaphtho[2,3-b]furan-4,9-dione in the presence of an asymmetric ruthenium complex and a hydrogen donor.

Abstract: The present invention provides a method for easily and inexpensively preparing a racemate or an optically-active 2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione in high yields, 2-acetyl-2,3-dihydro-5-hydroxynaphtho[2,3-b]furan-4,9-dione which is useful as an intermediate for preparing NFD, and an anticancer agent comprising 2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione as an active ingredient. Said 2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione is obtained in 4 or 5 steps by using comparatively inexpensive 5-hydroxynaphthalene-1,4-dione (also referred to as juglone) as a starting material.

Abstract: An object of the present invention is to provide a method for efficiently preparing (S)-2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]-furan-4,9-dione useful as a medicine at a low cost and in large amounts. According to the present invention, the desired (S)-2-(1-hydroxyethyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione can be prepared with high efficiency at a low cost and in large amounts by asymmetrically reducing 2-acetyl-5-hydroxynaphtho[2,3-b]furan-4,9-dione in the presence of an asymmetric ruthenium complex and a hydrogen donor.

Abstract: Carcinogenesis inhibitors containing as the active ingredient carotenoids extracted from the pure-line species of paradicsom paprika (species classified as Capsicum annuum L. var. grossum), etc., such as capsanthin, its fatty acid esters, capsorubin diesters, capsanthin 3,6-epoxide, capsorubin and cucurbitaxanthine A-3′ ester. These carcinogenesis inhibitors and paradicsom paprika extracts originate in natural substances and, therefore, make it possible to provide excellent Epstein-Barr virus genome inactivating agents. Thus, they are expected as being useful in preventing carcinogenesis and, based on their effects, applicable in various fields including drugs, cosmetics and health foods.

Abstract: A method of reducing the percentage of Epstein-Barr virus genome-carrying cells which exhibit Epstein-Barr virus early antigen induction, where the Epstein-Barr virus genone-carrying cells have been cultivated in the presence of at least one tumor-promoting chemical. The method is carried out by cultivating Epstein-Barr virus genome-carrying cells in the presence of a tumor-promoting chemical; and treating the Epstein-Barr virus genome-carrying cells with betanins. The betanins are effectively reduce the incidence of Epstein-Barr virus early antigen induction in the cultivated Epstein-Barr virus genome-carrying cells.

Abstract: A method of reducing the percentage of Epstein-Barr virus genome-carrying cells which exhibit Epstein-Barr virus early antigen induction, where the Epstein-Barr virus genome-carrying cells have been cultivated in the presence of at least one tumor-promoting or tumor-inducing chemical. The method is carried out by cultivating Epstein-Barr virus genome-carrying cells in the presence of a tumor-promoting or tumor-inducing chemical; and treating the Epstein-Barr virus genome-carrying cells with a synthetic fluorescein dye. The dyes effectively reduce the incidence of Epstein-Barr virus early antigen induction in the cultivated Epstein-Barr virus genome-carrying cells.

Abstract: A method of preventing inflammation of epidermal tissue resulting from exposure to a chemical by topically applying an acetone solution containing a natural colorant to the exposed tissue. The natural colorant is preferably a paprika extract containing a mixture of capsanthin, capsorubin, and their acyl esters, or an annatto seed extract containing a mixture of cis-bixin, trans-bixin, and cis-norbixin.

Abstract: The invention relates to a method of determining the effect of betanins on tumor formation in epidermal tissue in mammals which have been exposed to a substance which initiates or promotes tumor formation by sequentially exposing a first group of mammals to a topically applied chemical substance selected from the group consisting of tumor promoters and tumor initiators; providing the first group of mammals with drinking water containing betanins, said betanin having been extracted from beetroot; measuring a percentage of mammals in the first group which exhibit epidermal tumors; and comparing the percentage of mammals in the first group which exhibit epidermal tumors to a percentage of mammals in a second group which exhibit epidermal tumors, said mammals in the second group having been (a) exposed to a chemical substance selected from the group consisting of tumor promoters and tumor initiators and (b) providing with drinking water containing no betanins.

Abstract: A novel antitumor compound, 2-(1-hydroxyethyl)-5-hydroxynaphto [2,3-b]furan-4,9-dione, having the following formula is provided.

Abstract: An anti-skin tumor promotor comprising a compound of the general formula ##STR1## wherein R means a hydrogen atom or a hydroxyl group. The promotor may be an extract of the crude drug Scutellaria or a synthetic compound.