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The title nanoparticles are hydrothermally prepared from aqueous mixtures of N-acetyl-L-cysteine, CuCl2, InCl3, and Na2S (autoclave, 180 °C, 5—20 min).

Optically active cobalt(II) salen complexes were found to be effective Lewis acid catalysts for the enantioselective Michael addition of O -alkylhydroxylamines to nitroalkenes to afford the corresponding N -alkylhydroxyl-1,2-nitroamines in high yields and with good to high enantioselectivities. This study represents the first example of a transition-metal-catalyzed asymmetric Michael addition of amines to nitroalkenes.

A Co/TiO2 catalyst shows high activity in the dehydrogenation of various secondary alcohols (I) and (III) to afford the corresponding ketones.

A reusable Ni-loaded ceria catalyst is prepared and successfully used in the transfer hydrogenation of a variety of ketones with iPrOH.

The catalytic, enantioselective bromolactonization of internal alkenoic acids is developed by using trisimidazoline as chiral catalyst.

The direct synthesis of N-benzyl-substituted anilines is achieved for the first time by reaction of nitrobenzenes (I) with benzylic alcohols (II) in the presence of a heterogeneous Ag—Al2O3 catalyst.

A newly developed heterogeneous bimetallic Cu0.95Ag0.05/Al2O3 catalyst prepared by impregnation and H2-reduction at 600 °C is used for the effective N-alkylation of anilines and aliphatic amines with alcohols under mild reaction conditions without any co-catalysts.

It is found that treatment of distorted Ru(IV)-oxo species on ceria or zirconia with HCOONa leads to low-valent Ru compounds which efficiently promote the coupling of acrylates with some alkynes as well as norbornene.

We describe the necessity of the C 3 -symmetry and the role of a third imidazoline of trisimidazoline 3 , which was recently developed by us as a new entry of organocatalyst. The utility of 3 as a Bronsted base catalyst in the nitro Michael reaction and the α-amination of β-ketoesters was shown, and the recyclability of the catalyst was also demonstrated.

The photolysis of (2,4,6-tri-t-butylphenyl)bis(trimethylsilyl)phosphine in benzene gave products suggesting homolytic P–C bond cleavage followed by rearrangement and coupling.

Four novel phytoalexins, designated phytucassanes A, B, C and D, were isolated from rice ( Oryza sativa L.) leaves infected with Magnaporthe grisea (previously designated Pyricularia oryzae ) and from rice stems infected with Rhizoctonia solani . The structures of the phytocassanes, classified as cassane-type diterpenes, were determined by spectroscopic methods. Phytocassanes had high antifungal activity against the pathogenic fungi, M. grisea and R solani . The ED 50 values of phytocassanes A, B, C and D in prevention of spore germination of M. grisea were 20, 4, 7 and 25 μg/ml, respectively. Furthermore, large amounts of phytocassanes were produced in rice infected with the pathogenic fungi.

Large amounts of phytoalexins were produced in suspension-cultured rice cells by treatment with a mycelial extract of the potato pathogenic fungus Phytophthora infestans. Among them, a new cassane-type diterpene, designated phytocassane E, was isolated and identified as 1β-hydroxy-12,15-cassadien-3,11-dione. The ED50 values of phytocassane E in the prevention of spore germination and germ tube growth of the rice pathogenic fungus Magnaporthe grisea were 6 and 2 μg ml−1, respectively. This result, together with earlier results, suggests that the hydroxyl group at the C-1 position is the main functional moiety for the high antifungal activity of phytocassane E.

Dibenzocycloheptenylidene(2,4,6-tri-t-butylphenyl)-phosphine and fluorenylidene(2,4,6-tri-t-butylphenyl)-phosphine were prepared by the reactions of lithium silylphosphide with benzosuberenone and fluorenone, respectively. The reactions of the phosphines with sulfur were carried out to compare the results with those of the corresponding diphenyl derivative, and the new findings are discussed in terms of steric hindrance based on the results of the X-ray crystallographic analyses for dibenzocycloheptenylidenephosphine and its sulfide and the computational structure for the fluorenyl derivative. © 1997 John Wiley & Sons, Inc. Heteroatom Chem 8: 375–382, 1997

Reaction of methyl 2,3-anhydro-5,6-O-cyclohexylidene-β-D-allofuranoside with 2-methyl-2-propenylmagnesium chloride selectively gave methyl 5,6-O-cyclohexylidene-3-deoxy-3-C-(2-methyl-2-propenyl)-β-D-glucofuranoside, which was converted into the C1∼C10 fragment of carbonolide B by a sequence of reactions involving hydroboration of the prochiral double bond, oxidative cleavage between C5C6, and subsequent stereoselective three-carbon elongation at the C5 position.

Fullerene tweezers which have a rigid acetylenic spacers were synthesized and their inclusion abilities for C60 were examined by UV spectroscopy. From the spectra, the association constants were determined using Benesi-Hildebrand method. Fullerene tweezers with a 1,4-bis(4-oxycarbonylphenyl)butadiyne spacer showed the highest association constant for C60 (39300 ± 250 dm3mol−1 in benzene).

On the basis of our Pd enolate chemistry, we have succeeded in developing an efficient catalytic enantioselective fluorination of β-ketophosphonates. In the presence of chiral Pd complexes 1 (1–10 mol %), various substrates including cyclic and acyclic β-ketophosphonates underwent the reaction with N -fluorobenzenesulfonimide (NFSI) in EtOH to give the corresponding fluorinated products in a highly enantioselective manner (94–98% ee).

To reverse the adverse reactions of alkylxanthines and to develop novel inhibitors of cyclic AMP phosphodiesterase 4 (PDE4), a series of heterocycle [a]-, [b]-, [c,d]-, and [i]-condensed purines were designed and synthesized. Although all compounds did not display PDE1 and PDE3 inhibitory activities, several heterocycle [i]-condensed purines strongly inhibited PDE4. Especially, dl-3,4-dipropyl-8-methyl-4,5,7,8-tetrahydro-1H-imidazo[2,1-i]purin-5-one (dl-7c) exhibited comparable PDE4 inhibitory activity (IC(50)=1.9 microM) to rolipram and denbufylline (DBF).