Takanao Matsui

Synthesis of aminomethylated calix[4]resorcinarenes

Abstract Aminomethylation at the ortho position with respect to hydroxyl groups of calix[4]resorcinarenes, resorcinol-aldehyde cyclotetramers, was achieved by the Mannich reaction with formaldehyde and the appropriate amine in an alcoholic solution.

Antimicrobial activity of heartwood components of sugi (Cryptomeria japonica) against several fungi and bacteria

Methanol extract of sawdust of sugi (Cryptomeria japonica) heartwood was fractionated with toluene and n-hexane to give solvent-soluble and solvent-insoluble fractions. The n-hexane-soluble fraction showed the most inhibition activity among the fractions against phytopathogenic microorganisms, namely Fusarium oxysporum, Phytophthora capsici, Pythium splendens, and Ralstonia solanacearum. Sandaracopimarinol and ferruginol, isolated from the n-hexane-soluble fraction, showed moderate antifungal activity against the three fungi and strong antibacterial activity against R. solanacearum. The content of sandaracopimarinol (7.07 g/kg based on the dried sawdust) in the heartwood was about twice that of ferruginol. Sandaracopimarinol and ferruginol strongly inhibited the growth of Gram-positive bacteria but did not show inhibitory action against Gram-negative bacteria except for R. solanacearum. The antibacterial effect of sandaracopimarinol was first found in the present study and was stronger than that of ferruginol.

Antitumor activity of (10E, 12Z)-9-hydroxy-10,12-octadecadienoic acid from rice bran

Two types of hydroxy acids, (10E, 12Z)-9-hydroxy-10,12-octadecadienoic acid [1] and (9Z, 11E)-13-hydroxy-9,11-octadecadienoic acid [2], were obtained as cytotoxic compounds from a water extract of rice bran. The cytotoxicity of acid 1 was stronger than that of acid 2 in vitro, against P388 mouse leukemia cells. Acid 1 slightly inhibited the growth of a Balbc mouse 3T3 fibroblast cells (BALBc 3T3), but strongly inhibited that of simian virus 40-transformed 3T3 cells (SV-T2); 1 was therefore, found to have cytotoxicity against cancer cells. On the other hand, 2 inhibited neither normals cells nor transformed cells. Intraperitoneal injection of acid 1 effectively prolonged the survival time of C3HHeJ mice after intraperitoneal transplantation of MM46 mammary tumor cells. The difference in antitumor activity between 1 and 2 was also observed in vivo.

Silica gel-catalyzed β-O-glucosylation of alcohols with 1,2-anhydro-3,4,6-tri-O-pivaloyl-α-d-glucopyranose

1,2-anhydro-3,4,6-tri-O-pivaloyl-α-d-glucopyranose (1a) was allowed to react with alcohols in the presence of solid acids such as silica gel and zeolite HY, to afford β-O-glucosides stereoselectively. Several natural glucosides were synthesized by the application of the present reaction.

Preparation and Properties of Gelatin-Immobilized β-Glucosidase from Pyrococcus furiosus

Hyperthermostable β-glucosidase from Pyrococcus furiosus was enclosed in gelatin gel by cross-linking with transglutaminase. Gelatin-immobilized β-glucosidase was considerably more thermostable than the native enzyme. Lyophilized immobilisate was stored at 90 °C for 1 month without loss of activity. The immobilized β-glucosidase catalyzed transglucosylation of 5-phenylpentanol with 10.0 equivalent of cellobiose at pH 5.0 and 70 °C for 12 h to afford 5-phenylpentyl β-D-glucopyranoside in 41% yield. The immobilized enzyme was more effective than the native one in transglucosylation. The gelatin-immobilized Pfu-β-glucosidase recovered from the first run of the reaction was reusable on successive runs.

A Convenient Synthesis of Methyl 4-Substituted Benzoates via Diels-Alder Reaction in the Presence of Palladium on Activated Carbon

Abstract The thermal reaction of methyl 2-oxo-2H-pyran-5-carboxylates with substituted styrenes in the presence of 10% palladium on activated carbon afforded directly the corresponding methyl 4-biphenylcarboxylates in good yields. By the similar procedure, methyl 4-heteroaryl- and 4-alkyl-substituted benzoates were obtained from heteroaromatic olefins and alkenes, respectively.

Enantioselective syntheses of 10-oxo-11(E)-octadecen-13-olide and related fatty acid

Abstract The first, and short-step, syntheses of S and R enantiomers of 10-oxo-11( E )-octadecen-13-olide ( 1 ) and its seco-acid 2 , cytotoxic fatty acid derivatives from corn, were achieved from linoleic acid ( 3 ) by the combined use of lipoxygenase-catalyzed asymmetric oxygenation and cobalt porphyrin-catalyzed reduction-oxygenation as key-step reactions.

Facile and general method for preparation of (E)-4-hydroxy-2-alkenals.

A facile one-pot synthesis of (E)-4-hydroxy-2-alkenals such as (E)-4-hydroxy-2-nonenal, (E)-4-hydroxy-2-heptenal, and (E)-4-hydroxy-2-hexenal was achieved from the corresponding (2E,4E)-2,4-alkadienals by reduction-oxygenation with molecular oxygen and triethylsilane in the presence of cobalt(II) porphyrin as a catalyst followed by treatment with trimethylphosphite.

Microwave‐assisted Synthesis of N‐Hydroxyphthalimide Derivatives

Abstract N‐Hydroxyphthalimide derivatives are readily obtained in good yields by the reaction of phthalic anhydrides with hydroxylamine hydrochloride in the presence of pyridine under microwave irradiation.

Microwave-Assisted Beckmann Rearrangement of Aryl Ketoximes Catalyzed by In(OTf)3 in Ionic Liquid

Abstract Beckmann rearrangement of aryl ketoximes catalyzed by In(OTf)3 gave amides in ionic liquid under microwave irradiation. Aryl ketoximes were converted to corresponding amides in good yield within very short times (10–270 s). The catalyst and the ionic liquid were easily recovered and reused.