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Polycrystalline CaCu3Rh4O12 is prepared from a stoichiometric mixture of CaO, CuO, Rh2O3, and KClO4 under high-pressure and high-temperature conditions (Pt capsule, 1273 K, 15 GPa, 30 min).

Scabichelin and turgichelin, novel tris-hydroxamate siderophores, were isolated from Streptomyces antibioticus NBRC 13838/Streptomyces scabies JCM 7914 and Streptomyces turgidiscabies JCM 10429, respectively. The planar structures of scabichelin and turgichelin were elucidated by mass spectrometry, and 1- and 2-D NMR spectroscopic analyses of their gallium(III) complexes. The relative and absolute stereochemistry of the metabolites was determined by the modified Marfey's method in conjunction with computational modelling and NOESY NMR analysis of Ga-scabichelin and Ga-turgichelin. Genome sequence analysis of the plant pathogen Streptomyces scabies 87.22 identified a gene cluster containing a gene encoding a nonribosomal peptide synthetase (NRPS) that was predicted to direct the production of a pentapeptide with structural similarities to scabichelin and turgichelin. Comparative LC-MS/MS analyses of iron-deficient culture supernatants from wild type S. scabies 87.22 and a mutant in which the NRPS gene had been disrupted, and scabichelin purified from S. antibioticus, showed that scabichelin is the metabolic product of the cryptic gene cluster, strongly suggesting that it functions as a siderophore.

The decarbonylative cycloadditions of phthalic anhydrides with allenes were performed by using nickel catalyst. The asymmetric variant of the cycloaddition was also achieved by using chiral phosphine ligands to provide δ-lactones enantioselectively.

Tandem Michael—aldol, double Michael, and double Michael—aldol reactions with the chiral amine (I) allow efficient and stereoselective access to functionalized amines with up to five contiguous chiral centers in one pot.

An efficient method for the alkylation of triflates with alkynyllithium reagents is described and the successful application of the method to the total synthesis of (+)-panaxacol is exemplified.

Lateral root-inducing compounds, isolated from the bacterium Erwinia quercina, have been synthesized by using a coupling reaction of chiral triflates derived from L- or D- tartrates and their biological activities examined.

The reactions of α-trimethylsiloxy-, α-methoxy-, and α-ethoxystyrene with dimethyl acetylenedicarboxylate (DMAD) and dimethyl fumarate (DMFM) have been investigated. With DMAD the 1 : 1 Diels–Alder and the 1 : 2 Diels–Alder ene adducts were obtained, while the reaction with DMFM gave novel open-chain adducts through alkyl group migration and incorporation of the solvent.

Intramolecular Diels-Alder reaction of benzynes, generated from orthohaloaniline derivatives by the action of lithium 2,2,6,6-tetramethylpiperidide, with furans has been developed as a novel route for the construction of tetrahydrobenzazepine skeletons

Two new condensed guaiazulenoid pigments, gorgiabisazulene and gorgiagallylazulene, have been isolated from a gorgonian Acalycigorgia sp. and their structures have been established on the basis of spectroscopic and chemical evidence.

An enantiomeric pair of ( S , S )- and ( R , R )-bipyrrolidine derivatives has been prepared from D- and L-tartaric acids or D-mannitol as optically active starting materials. Taking advantage of the C 2 -symmetric nature of these chiral sources, the synthetic sequence has been established by using efficient side chain elongation, stereospecific conversion of a vicinal diol into a diazido group via S N 2 inversion, and pyrrolidine ring formation via intramolecular substitution as the key steps.

A variety of chiral pyrazole and imidazole derivatived ligands have been prepared under high pressure conditions and their catalytic efficiency in the enantioselective addition of diethylzinc to benzaldehyde has been examined.

Three new indolequinones, 6-methoxyindole-4,7-quinone (1), 5-methoxyindole-4,7-quinone (2) and 5-methylindole-4,7-quinone (3) were isolated from the mid-intestinal gland of the muricid gastropod Drupella fragum. The structures of 1 and 2 were established by spectroscopic methods and total synthesis, whereas the structure of 3 was elucidated mainly by NMR spectroscopic analyses. Compounds 1 ∼ 3 exhibited moderate antimicrobial activities against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli with MIC = 6.25 ∼ 50 μg/mL.

(2S,5S)-5-(3-Formyl-6-iodo-4-methoxybenzyl)-1-t-butoxycarbonyl-2-t-butyl-3-methyl-4-imidazolidinone (11), a chiral intermediate towards NCA PET tracer 6-[18F]fluoro-L-dopa (1), was synthesized from 3-iodoanisole in four steps. 3-Iodoanisole was first bischloromethylated to 2,4-bis(chloromethyl)-5-iodoanisole (14). Regio- and enantio-selective alkylation of 14 with (S)-1-(t-butoxycarbonyl)-2-t-butyl-3-methyl-4-imidazolidinone (12) afforded 33, which was then hydrolyzed and oxidized to the desired intermediate 11.

Auriculol, a cytotoxic oxygenated squalene, was isolated from the Japanese sea hare Dolabella auricularia , and its stereostructure was elucidated by spectral analysis and organic synthesis.

Reactions of hydrosilanes, R4−nSiHn (R = alkyl or phenyl, n = 1–3), with 2 equiv of CuBr2 in the presence of a catalytic amount of CuI led to selective replacement of an H–Si bond with a Br–Si bond giving R3SiBr, R2SiHBr, or RSiH2Br, while treatment of R2SiH2 and RSiH3 with 4 equiv of the reagent produced R2SiBr2 and RSiHBr2, respectively. Similar reaction of Het2SiSiEt2H afforded Het2SiSiEt2Br.

A novel shunt product, actinoperylone, has been isolated from a deletion mutant of the actVA-ORF5 and ORF6 genes involved in the biosynthesis of a benzoisochromanequinone (BIQ) antibiotic actinorhodin (ACT) in Streptomyces coelicolor A3(2). Spectroscopic analysis revealed its perylenequinone-type skeleton with the four chiral centers, obviously derived from the dimerization of an ACT intermediate. The structure of actinoperylone indicates the essential role of ActVA-ORF5 in the oxygen introduction at C-6, which is common to the formation of BIQ chromophore. The present results also agree with the distribution of the actVA-ORF5 homologues in all known BIQ biosynthetic clusters in streptomycetes.

From the stems of Cyathocalyx crinatus, a rain forest plant in Borneo, six new Diels–Alder adducts, named crinatusins A1, A2, B1, B2, C1, and C2, together with a known chalcone derivative, 4′,6′-dihydroxy-3′,5′-dimethyl-2′-methoxychalcone, have been obtained. Their structures were determined on the basis of spectroscopic data and chemical methods. Crinatusins showed a lethal toxicity against brine shrimp.

A new synthesis of [2,3]naphthoporphyrins using 4,9-ethano-2H-benz[f]isoindole as a synthon of 2H-benz[f]- isoindole is described; soluble precursors of [2,3]naphthoporphyrins are converted into insoluble [2,3]naphthoporphyrins by simply heating at 290 °C.