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Recombinant Escherichia coli, carrying the crtE, crtB, crtI, crtY, and crtZ genes from the bacterium Pantoea ananatis in addition to the Haematococcus pluvialis idi gene, can dominantly produce zeaxanthin. Vigorous rotary-shaking culture of the recombinant cells to promote strong aeration led to the production of two structurally similar polar carotenoids [1 (3.7%) and 2 (2.9%)] and eschscholtzxanthone (2.3%), along with zeaxanthin (72.6%), β-cryptoxanthin (7.3%), β-carotene (7.1%), and rubixanthin (2.1%). Carotenoids 1 and 2 were purified, and their structures were determined as (6E)-9′-apo-rohodoxanthinone and (6Z)-9′-apo-rhodoxanthinone, respectively, based on UV–vis, MS, 1H NMR, and 13C NMR spectral data. These novel compounds were shown to exhibit excellent singlet oxygen-quenching activity by the methylene blue-sensitized photooxidation system.

A bromide-catalyzed oxidation of alcohols was developed which proceeded in the presence of an alkali metal bromide and an oxidant under mild conditions. The reaction involved an organic-molecule-free oxidation using KBr and Oxone and a Bronsted acid assisted oxidation using KBr and aqueous H2O2 solution to provide a broad range of carbonyl compounds in high yields. Moreover, the bromide-catalyzed oxidation of primary alcohols enabled the divergent synthesis of carboxylic acids and aldehydes under both reaction conditions in the presence of TEMPO. A possible catalytic mechanism was suggested on the basis of various mechanistic studies.

An efficient synthesis of 6-substituted 3-(alkoxycarbonyl)-5-aryl-α-pyrones is reported. This methodology consists of the successive manipulation of an addition–elimination reaction between benzyl ketone derivatives and dimethyl methoxymethylenemalonate, and an acid-catalyzed condensation reaction. The synthesis is applicable to various 5-p-substituted-aryl 6-substituted α-pyrones and good to excellent yields were obtained over two steps from benzyl ketone derivatives that were easily prepared from phenylacetic acid by the Negishi coupling or the Claisen decarboxylation reaction.

The new copper-catalyzed intramolecular and intermolecular alkoxylation of azoles proceeds under base-free conditions even on gram scale.

The total synthesis of auripyrone A (Ia) and B (Ib) is presented and their cytotoxicities against a panel of 39 human cancer cell lines is investigated.

The diastereoselective aldol-type reaction and the Mukaiyama aldol-type reaction of γ-pyrones are reported.

K0.59VII1.59VIII0.41 [NbIV(CN)8] ·(SO4)0.50·6.9H2O precipitates from an aqueous solution of K4[Nb(CN)8], VSO4, and VCl3 at -3 °C.

A wide scope of carbonyl compounds is generated by thermal oxidation and photooxidation by visible light or natural sunlight, depending on the substituents of the alkylarenes.

Chiral imidazolinones are incorporated into the main-chain of the polymer by ionic bonding.

Several title compounds of type (VI), (VIII), or (IX) are evaluated for their antifungal activities.

Treatment of 1-(α-hydroxybenzyl)- and 3-(α-hydroxybenzyl)indolizines with trifluoroacetic acid in dichloromethane gave phenylbis(α-indolizinyl)methanes, bis[α-(indolizinyl)benzyl] ethers and indolizines, depending upon the presence or absence of the substituent at the 2- or 5-position and the reaction conditions used.

Treatment of 2,3-dihydro-2-methyl-3-phenyl-1H- pyrazino 3,4,5-cd indolizine 2-oxides (5) with trifluoroacetic anhydride gave new heterocyclic six-membered betaines (6) which underwent 1,3-dipolar cycloaddition reaction with dimethyl acetylenedicarboxylate and maleimides in hot toluene to yield the corresponding cycloadducts (7) and (8). Treatment of the maleimide adducts (8) with p-toluenesulfonic acid in boiling acetic acid gave the [2.3.4]cyclazines (9)

A new, general synthesis of N-benzoyl-2-arylethenesulfonamides by the reaction of aryl halides including heteroaryl halides with [2-(benzoylsulfamoyl)ethyl]pyridinium chloride in the presence of palladium acetate is described.

The unusual reactivity of [6](1,4)naphthalenophane (2) and [6](1,4)anthracenophane (3), the smallest-bridged acenophanes hitherto known, in electrophilic reactions has been disclosed. These reactions include (i) acid-catalyzed telomerization, (ii) peracid oxidation, and (iii) addition with dienophiles. Semi-empirical molecular orbital calculations (MNDO and MNDO/PM3) were performed in order to compare the geometries, energies, and bonding characters of 2 and 3 with those of [6]paracyclophane (1)

C-nor-4,6-Secocamptothecin 2, 4-ethyl-4-hydroxy-6-(2-quinolinyl)-1H-pyrano[3,4-c]pyridine-3,8(4H,7H)-dione, lacking the C-ring of camptothecin 1, and its related compounds 3 and 4 were prepared from ethyl quinoline-2-carboxylate 7. By an analogous reaction sequences, synthesis of 6-(2-pyridinyl)-1H-pyrano[3,4-c] pyridine-3,8(4H,7H)-dione derivatives 5 and 6, which contain the B, D, and E ring of 1, were achieved

The reaction between 2,6-bis(hydroxylmethyl)-4-methylphenol and benzylamine afforded N,N′,N″-tribenzyl-6,15,24-trimethyl-9,18, 27-trihydroxy-2,11,20-triaza[3.3.3]metacyclophanes.

An enzymatic method for simultaneous performance of separation and analysis of (meso/racemic)-diesters, i.e. 1,4-bis-(1-acetoxyethyl)benzene ( 3a ) and 1,4-bis-(1-acetoxyisopropyl)benzene ( 3b ), was demonstrated.

Nalidixic acid is a synthetic antibacterial agent active against Gram-negative organism. Since the introduction of Nalidixic acid in 1962, a large number of quinolone carboxylic acids have been synthesized. Early in the 1980's new agents such as norfloxacin, enoxacin, ofloxacin and ciprofloxacin, possessing the 6-fluoro substituent and the 7-piperazinyl group on the quinolone pharmacophore and collectively known as new quinolones or fluoroquinolones, were reported to have greatly improved potency and antibacterial spectra relative to old quinolones.Subsequently, considerable interest has been increasingly given to the structural manipulation of substituents on quinolone nucleus and detailed data for structure-activity relationships have been accumulated. This review will focus primarily on the recent advance in medicinal chemical studies of new quinolones in consideration of in vitro antibacterial activity, pharmacological properties, and physicochemical properties.

The chemical structure of claudimerin-A (1), a novel dimeric coumarin from roots of Citrus hassaku (Rutaceae), have been elucidated by spectrometric studies and a single crystal X-ray analysis. The structure of 1 consisted of two clausarin (2) units linked symmetrically with the forming of the pyranopyran ring.

Crystalline carbon nitride was easily synthesized from CN radicals prepared by the reaction between N atoms and a graphite rod anode in the argon-nitrogen plasma arc at atmospheric pressure. The deposits on Si(111) wafer substrate were identified as β-C 3 N 4 by the x-ray diffraction method, and the C-N bond was detected in the deposit by infrared (IR) spectroscopy and x-ray photoelectron spectroscopy (XPS). The existence of sp3 orbital on the C atom in C 3 N 4 is presumed from the XPS spectra of the valence band of the deposit

One-step formation of guaian-8,12-olide derivatives, α-methylene-γ-lactones fused to a perhydroazulene carbon framework with various stereochemistries, were performed from monocyclic compounds via intramolecular cyclization of ω-formyl-α-trimethylsilylmethyl-α,β-unsaturated esters. Stereochemical features of both Lewis acid- and fluoride-promoted cyclizations are discussed.

The structure of furobinordentatin, isolated from the root of Citrus yuko (Rutaceae), has been elucidated by spectroscopic studies and a single crystal X-ray analysis as 1. Furobinordentatin is a novel type of bicoumarin composed of two nordentatin (2) units linked with the forming of a dihydrofuran ring.