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Biomedical subjects

I Kitagawa

Publications and source records attributed to I Kitagawa.

At least 55 records · Page 3Linked to original sources
PubMed1994

Indonesian medicinal plants. VII. Seven new clerodane-type diterpenoids, peronemins A2, A3, B1, B2, B3, C1, and D1, from the leaves of Peronema canescens (Verbenaceae).

Seven new clerodane-type diterpenoids, named peronemins B2 (1), A2 (2), B1 (3), C1 (4), B3 (5), A3 (6), and D1 (7), were isolated from the leaves of Peronema canescens (Verbenaceae), an Indonesian medicinal plant collected in Bengkulu, Sumatera Island, Indonesia. The chemical structures of 1-7 have been elucidated on the basis of their chemical and physicochemical properties.

Diterpenes↗
PubMed1994

Chemical studies of Chinese licorice-roots. I. Elucidation of five new flavonoid constituents from the roots of Glycyrrhiza glabra L. collected in Xinjiang.

From the air-dried roots of Glycyrrhiza glabra L. (Leguminosae) collected in Xinjiang province, China ("Shinkyo-Kanzo" in Japanese), five new flavonoid compounds named glucoliquiritin apioside (1) (a flavonone bisdesmoside), prenyllicoflavone A (5) (a bisprenylflavone), shinflavone (7) (a prenylated pyranoflavanone), shinpterocarpin (9) and 1-methoxyphaseollin (12) (both pyranopterocarpans), were isolated together with eight known saponins, seven known flavonoid glycosides, and eleven flavonoids. The structures of the new compounds have been elucidated on the basis of their chemical and physicochemical properties.

Chromatography, High Pressure Liquid↗
PubMed1994

Escins-Ia, Ib, IIa, IIb, and IIIa, bioactive triterpene oligoglycosides from the seeds of Aesculus hippocastanum L.: their inhibitory effects on ethanol absorption and hypoglycemic activity on glucose tolerance test.

Five triterpene oligoglycosides named escins-Ia, Ib, IIa, IIb, and IIIa were isolated from the seeds of Aesculus hippocastanum L. and their chemical structures were determined on the basis of chemical and physicochemical evidence. Escins-Ia, Ib, IIa, and IIb were found to exhibit inhibitory effect on ethanol absorption and hypoglycemic activity on oral glucose tolerance test in rats. Among them, escins-IIa and IIb showed the higher activities for both bioassays, while desacylescins-I and II had no activity.

Animals↗
PubMed1994

Marine natural products. XXXIII. Theonellapeptolide IId, a new tridecapeptide lactone from the Okinawan marine sponge Theonella swinhoei.

Following the characterization of theonellapeptolides Ia-Ie (2-6), another new tridecapeptide lactone named theonellapeptolide IId (1) was isolated from the Okinawan marine sponge Theonella swinhoei. The structure of 1 has been determined on the bases of chemical and physicochemical examinations which included an HPLC-CD combined analysis of the amino acid composition. Theonellapeptolide IId (1) prevented fertilization of the sea urchin Hemicentrotus pulcherrimus at the concentration of 25 micrograms/ml or greater but did not affect early embryonic development of fertilized eggs up to the gastrula stage.

Amino Acid Sequence↗
PubMed1994

Indonesian medicinal plants. VIII. Chemical structures of three new triterpenoids, bruceajavanin A, dihydrobruceajavanin A, and bruceajavanin B, and a new alkaloidal glycoside, bruceacanthinoside, from the stems of Brucea javanica (Simaroubaceae).

Three new apotirucallane-type triterpenoids named bruceajavanin A (1) dihydrobruceajavanin A (2) and bruceajavanin B (3), and a novel beta-carboline alkaloidal glycoside named bruceacanthinoside (4) were isolated from the stems of Brucea javanica (Simaroubaceae), a traditional medicine used to treat malaria in the Bengkulu area, Sumatra, Indonesia. Their chemical structures have been elucidated on the bases of their chemical and physicochemical properties. Bruceajavanin A (1), dihydrobruceajavanin A (2) and bruceacanthinoside (4) were shown to inhibit growth of the cultured malarial parasite Plasmodium falciparum K1 of a chloroquine-resistant strain.

Animals↗
PubMed1994

Indonesian medicinal plants. IX. Chemical structures of gongganosides A, B, and C, three new quinovic acid glycosides from the bark of Bhesa paniculata (Celastraceae).

Three new quinovic acid glycosides, named gongganosides A (1), B (2), and C (3), were isolated from the bark of Bhesa paniculata (Celastraceae), an Indonesian medicinal plant collected in Sumatra Island. The chemical structures have been elucidated on the basis of chemical and physicochemical evidence as quinovic acid 3-O-beta-D-xylopyranosyl(1-->3)-alpha-L- rhamnopyranoside for 1,28-O-beta-D-glucopyranosylquinovic acid 3-O-alpha-L-rhamnopyranoside for 2, and 28-O-beta-D-glucopyranosyl-quinovic acid 3-O-beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranoside for 3.

Carbohydrate Sequence↗
PubMed1994

Indonesian medicinal plants. X. Chemical structures of four new triterpene-glycosides, gongganosides D, E, F, and G, and two secoiridoid-glucosides from the bark of Bhesa paniculata (Celastraceae).

Four new triterpene-glycosides, named gongganosides D (4), E (5), F (6), and G (7), and two new secoiridoid-glucosides, (7R)-7-caffeoyloxysweroside (8) and (7S)-7-caffeoyloxysweroside (9), were isolated from the bark of the Indonesian medicinal plant Bhesa paniculata (Celastraceae). The chemical structures have been elucidated on the bases of their chemical and physiocochemical properties.

Carbohydrate Sequence↗
PubMed1994

Marine natural products. XXXI. Structure-activity correlation of a potent cytotoxic dimeric macrolide swinholide A, from the Okinawan marine sponge Theonella swinhoei, and its isomers.

Acidic treatment of swinholide A (1), which was characterized as the major cytotoxic macrolide from the Okinawan marine sponge Theonella swinhoei, provided several isomeric macrolides having different size of the dilactone ring structure. From the structure-activity correlation viewpoint, the in vitro cytotoxicities and in vivo antitumor activities of these dimeric macrolides, together with two monomeric macrolides which were synthesized from 1, have been examined.

Animals↗
PubMed1994

Marine natural products. XXXIV. Trisindoline, a new antibiotic indole trimer, produced by a bacterium of Vibrio sp. separated from the marine sponge Hyrtios altum.

A new antibiotic indole trimer named trisindoline (1) was isolated, together with a known dioxopiperazine brevianamide F (2), from the culture of a bacterium of Vibrio sp., which was separated from the Okinawan marine sponge Hyrtios altum. The structure of trisindoline (1) has been determined on the bases of physicochemical evidence and chemical synthesis.

Animals↗
PubMed1994

Marine natural products. XXXII. Absolute configurations of C-4 of the manoalide family, biologically active sesterterpenes from the marine sponge Hyrtios erecta.

Cytotoxic sesterterpenes, manoalide 25-acetals (1a, 1b), seco-manoalide (2), (E)-neomanoalide (3), (Z)-neomanoalide (4), and heteronemin (6), were isolated from the marine sponge Hyrtios erecta (collected at Amami Island, Kagoshima Prefecture, Japan) by bioassay-guided separation and the absolute configurations of these manoalide family members have been determined. Manoalide 25-acetals (1a, 1b) were shown to exhibit in vivo antitumor activity and to inhibit the DNA-relaxing activity of mouse DNA topoisomerase I and the DNA-unknotting activity of calf thymus DNA topoisomerase II.

Animals↗
PubMed1994

Chemical transformation of terpenoids. X. Ionophoretic activities of macrocyclic lactone epoxides synthesized from geraniol.

Two coronand-type 18-membered lactone epoxides, i.e., geranyl dimeric lactone diepoxide (GL2E2, 10) and tetraepoxide (GL2E4, 11), were synthesized from geraniol as diastereomeric mixtures. Among them, GL2E4 (11) was shown to exhibit ion-transport activity for Ca2+ ion in the test using a W-07 (liquid-membrane type) apparatus and ion-permeation activities for Ca2+ and K+ ions across the human erythrocyte membrane. Isolation of six component diastereomers of GL2E4 (11) [GL2E4-1 (11c), -2 (11d), -3 (11e), -4 (11f), -5 (11g), -6 (11h)], was effected by HPLC separation of two diastereomeric tetraepoxides (11a, 11b) which were prepared from two diepoxides (GL2E2-1, 10a and GL2E2-2, 10b). The relative stereostructures of these diastereomers were determined by a combination of X-ray diffraction and 1H-NMR analyses. Among the six diastereomers, S2-symmetrical GL2E4-4 (11f) exhibited the strongest ion-transport activity for Ca2+ ion while C2-symmetrical GL2E4-6 (11h) exhibited the strongest ion-permeation activity for Ca2+ ion across the human erythrocyte membrane.

Acyclic Monoterpenes↗
PubMed1993

Antifungal peroxyketal acids from an Okinawan marine sponge of Plakortis sp.

Antifungal peroxyketal acids and their methyl esters, the peroxyplakoric acids A1 methyl ester (1), A2 methyl ester (2), A3 methyl ester (3), B1 methyl ester (4), and B3 methyl ester (5), were separated from an Okinawan marine sponge of Plakortis sp. The absolute stereostructures 1-5 have been elucidated on the basis of chemical and physicochemical evidence.

Animals↗
PubMed1993

Saponin and sapogenol. XLVIII. On the constituents of the roots of Glycyrrhiza uralensis Fischer from northeastern China. (2). Licorice-saponins D3, E2, F3, G2, H2, J2, and K2.

Following the characterization of licorice-saponins A3 (2), B2 (3), and C2 (4), the chemical structures of licorice-saponins D3 (5), E2 (6), F3 (7), G2 (8), H2 (9), J2 (10), and K2 (11), seven of the ten oleanane-type triterpene oligoglycosides isolated from the air-dried roots of Glycyrrhiza uralensis Fischer collected in the northeastern part of China, were investigated. On the basis of chemical and physicochemical evidence, the structures of licorice-saponins D3, E2, F3, G2, H2, J2, and K2 have been determined to be expressed as 3 beta-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucuronopyranosyl(1-- >2)-beta-D-glucuronopyranosyloxy]-22 beta-acetoxyolean-12-en-30-oic acid (5), 3-O-[beta-D-glucuronopyranosyl(1-->2)-beta-D- glucuronopyranosyl]glabrolide (6), 3-O-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucuronopyranosyl(1--> 2)-beta-D-glucuronopyranosyl]-11-deoxoglabrolide (7), 24-hydroxyglycyrrhizin (8), 3-O-[beta-D-glucuronopyranosyl(1-->2)-beta- D-glucuronopyranosyl]liquiritic acid (9), 24-hydroxy-11-deoxoglycyrrhizin (10), and 3 beta-[beta-D- glucuronopyranosyl(1-->2)-beta-D-glucuronopyranosyloxy]-24-+ ++hydroxyoleana- 11,13(18)-dien-30-oic acid (11), respectively.

China↗
PubMed1993

Saponin and sapogenol. XLIX. On the constituents of the roots of Glycyrrhiza inflata Batalin from Xinjiang, China. Characterization of two sweet oleanane-type triterpene oligoglycosides, apioglycyrrhizin and araboglycyrrhizin.

Two sweet oleanane-type triterpene oligoglycosides named apioglycyrrhizin and araboglycyrrhizin were isolated from the air-dried roots of Glycyrrhiza inflata Batalin, collected in Xinjiang province (Shinkyo-Kanzo in Japanese), together with glycyrrhizin (3), licorice-saponins A3 (8), G2 (10), and H2 (11) and known flavonoid glycosides. On the basis of chemical and physicochemical evidence, the structures of apioglycyrrhizin and araboglycyrrhizin have been determined to be expressed as 3-O-[beta-D-apiofuranosyl(1-->2)-beta-D- glucuronopyranosyl]glycyrrhetic acid (1) and 3-O-[alpha-L- arabinopyranosyl(1-->2)-beta-D-glucuronopyranosyl]glycyrrhet ic acid (2), respectively. During the course of these studies, it has been found that the hydroxyl groups in the oligosaccharide moiety of the glucuronide saponins may be partially methylated by prolonged treatment with diazomethane in methanol. The sweetness of the saponins hitherto isolated from various Glycyrrhizae Radix has been examined and a structure-sweetness relationship, as compared with glycyrrhizin, has been found.

China↗
PubMed1993

Saponin and sapogenol. L. On the constituents of the roots of Glycyrrhiza uralensis Fischer from Xinjiang, China. Chemical structures of licorice-saponin L3 and isoliquiritin apioside.

From the air-dried roots of Glycyrrhiza uralensis Fischer collected in Xinjiang province, China ("Shinkyo-Kanzo" in Japanese), a new oleanene-type triterpene oligoglycoside named licorice-saponin L3 and a new chalcone oligoglycoside named isoliquiritin apioside were isolated together with glycyrrhizin, 18 alpha-glycyrrhizin, apioglycyrrhizin, araboglycyrrhizin, licorice-saponins A3, E2, G2, and H2, and six known flavonoid glycosides. On the basis of chemical and physicochemical evidence, the structures of licorice-saponin L3 and isoliquiritin apioside were elucidated as 3 beta-[alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1--> 2)-beta-D-glucuronopyranosyloxy]-22 beta-acetoxy-24-hydroxyolean-12-en-30-oic acid (1) and 4-O-[beta-D-apiofuranosyl(1-->2)-beta-D- glucopyranosyl]isoliquiritigenin (6), respectively.

Chalcone↗
PubMed1993

Saponin and sapogenol. XLVII. On the constituents of the roots of Glycyrrhiza uralensis Fischer from northeastern China. (1). Licorice-saponins A3, B2, and C2.

From the air-dried root of Glycyrrhiza uralensis, collected in the northeastern part of China, ten new oleanane-type triterpene oligoglycosides were isolated together with glycyrrhizin (1) and several known flavonoids. Among the newly isolated triterpene oligoglycosides, the chemical structures of licorice-saponin A3 (2), licorice-saponin B2 (3), and licorice-saponin C2 (4) have been determined, on the basis of chemical and physicochemical evidence, to be expressed as 30-O-beta-D-glucopyranosylglycyrrhizin, 11-deoxo-glycyrrhizin, and 3-O-[beta-D-glucuronpyranosyl(1-->2)-beta-D-glucuronpyranosyl++ +]oleana- 11,13(18)-dien-30-oic acid, respectively. During the course of these studies, facile conversions from glycyrrhizin (1) to licorice-saponins A3 (2), B2 (3), and C2 (4) have been accomplished.

Carbohydrate Sequence↗
PubMed1993

Altohyrtins B and C and 5-desacetylaltohyrtin A, potent cytotoxic macrolide congeners of altohyrtin A, from the Okinawan marine sponge Hyrtios altum.

Following the characterization of altohyrtin A (1), altohyrtins B (2) and C (3) and 5-desacetylaltohyrtin A (4) have been isolated from the Okinawan marine sponge Hyrtios altum and their plane structures and parts of their relative configurations elucidated. Three congeneric macrolides (2, 3, and 4) exhibit extremely potent cytotoxicities similar to those of 1 against KB cells with IC50 values of 0.02, 0.4, and 0.3 ng/ml, respectively.

Animals↗