Nobutoshi Murakami

Anti-tumour-promoting glyceroglycolipids from the green alga, Chlorella vulgaris

Two new monogalactosyl diacylglycerols were isolated from the freshwater green alga, Chlorella vulgaris, as anti-tumour promoters, together with three monogalactosyl diacylglycerols and two digalactosyl diacylglycerols. The new monogalactosyl diacylglycerol containing (7Z,10Z)-hexadecadienoic acid showed a more potent inhibitory effect toward tumour promotion than the other glycerolipids isolated.

Enzymatic transformation of glyceroglycolipids into sn-1 and sn-2 lysoglyceroglycolipids by use of Rhizopus arrhizus lipase

Abstract Lipase from Rhizopus arrhizus catalyzed deacylation of two classes of glyceroglycolipids, monogalactosyl diacylglycerol(MGDG). and digalactosyl diacylglycerol(DGDG), proceeded regiospecifically to furnish sn-1 lysoglyceroglycolipids quantitatively. The lipase also catalyzed complete acyl migration of sn-1 lysoglycerogalactolipids leading to sn-2 lysoglycerogalactolipids.

Synthesis and structure - anti-tumor-promoting activity relationship of monogalactosyl diacylglycerols

Abstract Monogalactosyl diacylglycerols (MGDG, 1a–t) were synthesized utilizing p-methoxybenzyl group for protection of hydroxyl groups at sugar moiety. Inhibitory activity of MGDG (1a–t) and related compounds on Epstein-Barr virus early antigen activation was evaluated as anti-tumor-promoting activity, and MGDG with oleoyl group (1c,h–j,p,s) showed strong activity.

Two unsaturated 9R-hydroxy fatty acids from the cyanobacteriumAnabaena flos-aquae f. flos-aquae

Abstract(9R-10E,12Z,15Z)-9-Hydroxyotadecatrienoic acid and (9R,10E,12Z)-9-hydroxyoctadecadienoic acid were isolated from the nitrogen fixing cyanobacteriumAnabaena flosaquae. f. flos-aquae and characterized as the corresponding methyl esters. This is the first report of the natural occurrence of 9R-oxygenated fatty acids.

Inhibition of 12-O-tetradecanoylphorbol-13-acetate promoted mouse skin papilloma by digalactosyl diacylglycerols from the fresh water cyanobacterium Phormidium tenue

To search for possible antitumor-promoters, two digalactosyl diacylglycerols (DGDGs), which were obtained from the freshwater cyanobacterium Phormidium tenue and possessed a single pair of acyl residues, were evaluated for their inhibitory effects on the two-stage carcinogenesis test in mouse skin. Papillomas in mouse skin were initiated with 390 nmol of 7,12-O-dimethylbenz[a]anthracene and 1 week later, were promoted twice a week with 1.7 nmol of 12-O-tetradecanoylphorbol-13-acetate (TPA). Two DGDGs effectively inhibited tumor formation in the sensitive mouse stock even when these compounds were given 1 h before TPA treatment.

A novel ring transformation of 5-acylaminouracils and 5-acylamino-pyrimidin-4(3H)-ones into imidazoles

Abstract 1, 3-Disubstituted 5-acylamino-6-methyluracils (2a-e) were transformed into 1, 2-disubstituted 4-alkylcarbamoyl-5-methyl-1 H -imidazoles (3a-e) by treatment with 5% aqueous sodium hydroxide in ethanol. Similarly, reaction of 5-acylamino-6-methyl-3-phenyl-4-(3 H )-pyrimidinones (5a-d) with 5% aqueous sodium hydroxide in ethanol gave 2-substituted 5-methyl-4-phenylcarbamoyl-1 H -imidazoles (6a-d).

STRUCTURAL ELUCIDATION OF THE 8-METHOXYPSORALEN OXIDIZED PRODUCT THAT INHIBITS THE CHEMOTACTIC ACTIVITY OF POLYMORPHONUCLEAR NEUTROPHILS TOWARD ANAPHYLATOXIN C5a

The chemical structure of the 8‐methoxypsoralen oxidized product that inhibits the chemo‐tactic activity of anaphylatoxin C5a was determined to be 2,3‐dihydro‐2,9‐dimethoxy‐3‐hydroxy‐7‐oxo‐7H‐futo[3,2‐g][l]benzopyran. Its minimal concentration required to obtain the maximum inhibition of C5a des Arg (1 times 10−8M) chemotactic activity is 2.5 times 10−8M. Bioactivity of this substance was maintained for 2 weeks, stored in a dark room at room temperature under aerobic conditions. There is a possibility that this substance may be useful in the treatment of immune complex diseases.

Chemoenzymatic synthesis of 1-O-acyl-3-O-(6'-O-acyl-β-D-galactopyranosyl)-sn-glycerol☆

Convenient synthesis of 1-O-acyl-3-O-(6-O-acyl-β-D-galactopyranosyl-sn-glycerol was studied. The lipase from Achromobacter sp. catalyzed acylation of 3-O-β-D-galactopyranosyl-sn-glycerol, which contains two primary hydroxyl functions, proceeded regioselectively to furnish 1-O-acyl-3-O-β-D-galactopyranosyl-sn-glycerol.

Selective preparation of sn-1 and sn-2 lysogalactolipids by enzymatic hydrolysis using lipase (from Rhizopus arrhizus)

Abstract Selective and quantitative transformations of galactolipids into sn -1 and sn -2 lysogalactolipids by the use of lipase (from Rhizopus arrhizus ) were developed.

Generation of lysoglyceroglycolipids in the cyanobacterium, Phormidium tenue

Two kinds of lysoglycolipids, monogalactosyl 1-monoacylglycerol and digalactosyl 1-monoacylglycerol were generated in the cyanobacterium, Phormidium tenue, when it was stored at -20 degrees for more than 1 month. By comparison of the compositions of fatty acid residues between monogalactosyl 1-monoacylglycerol and monogalactosyl diacylglycerol, digalactosyl 1-monoacylglycerol and digalactosyl diacylglycerol, respectively, the 1-monoacylgalactolipids were presumed to be formed by regioselective deacylation at the sn-1 position with subsequent acyl-group migration from the sn-2 to the sn-1 position. In contrast, 1-monoacyl derivatives of sulphoquinovosyl diacylglycerol and phosphatidylglycerol, the other membrane lipids contained in cyanobacteria, were not formed.