This work reports two new classes of non-toxic heterocyclic quaternary ammonium surfactants (HQASs) synthesized by condensation of a series of fatty acids with 2-morpholinoethan-1-amine and pyridin-4-ylmethanamine, followed by quaternization with benzyl bromide. Their critical micelle concentrat...

A novel synergistic system of combined ammonium and phosphonium type ionic liquids is reported for the first time, which displays pronounced synergistic effect in the extraction of Lu(III). The synergistic enhancement coefficients from different mole fractions of [P66614][EHEHP] and [N1888][BTMP...

The effect of the quaternary ammonium chitin structure on the bactericidal activity and specificity against Escherichia coli and Staphylococcus aureus was investigated. Quaternary ammonium chitins were synthesized by the separate acylation of chitin (CT) with carboxymethyl trimethylammonium chlo...

Gas-phase reactions of ozone (O3) with volatile organic compounds were investigated both by experiment and molecular simulations. From our experiments, it was found ozone readily reacts with VOC pure components and reduces it effectively. By introducing ozone intermittently, the reaction between...

Isoprenoids are important fine chemicals as material monomers, advanced fuels and pharmaceuticals. A variety of natural isoprenoids can be synthesized by engineered microbial strains. This work established a process by dividing the current isoprenoid pathway into the upstream fermentation proces...

Controlled conversion of 2-methyl-2-hepten-6-one (1) by Botrytis cinerea resulted in the formation of (S)-(+)-2-methyl-2-hepten-6-ol (sulcatol) (2) of 90% ee. In addition, (2R, 5R)- (3a), (2S,5S)- (3a′), (2R,5S)- (3b) and (2S,5R)-2-(1-hydroxy-1-methylethyl )-5-methyltetrahydrofuran (3b′), (3s,...

An open and a closed system were used to evaluate the effects of 6-methyl-5-hepten-2-one (MHO) vapor on peel browning or scald development of ‘Delicious’ and ‘Granny Smith’ (scald susceptible) or ‘Fuji’ and ‘Gala’ (scald resistant) apples. In the open system, fruit were placed on the top...

Sexually experienced male rats display penile erections when exposed to faeces from mammalian females in oestrus (Rampin et al., Behav Brain Res, 172:169, 2006), suggesting that specific odours indicate female receptiveness across species. However, it is unknown to what extent the sexual respons...

Rate coefficients for the gas-phase reactions of O3 molecules with three unsaturated oxygenated compounds have been determined using the relative kinetic technique in an environmental chamber with FTIR detection of the reactants at (298 ± 2) K in 760 Torr total pressure of synthetic air. The fo...

Vapor pressures and vaporization enthalpies for 5-nonanone, linalool and 6-methyl-5-hepten-2-one seem to be in disarray. Temperature dependences of vapor pressures for these pure compounds were measured by using the static and the transpiration techniques. Molar standard enthalpies of vaporizati...

Chemoselective flow hydrogenation of 6-methyl-5-hepten-2-one was performed over nano-nickel catalysts. The parent catalyst composed solely of nickel nanoparticles grafted on the polymeric resin exhibited high activity and selectivity towards CC bond saturation but its modification with small qua...

We report the design and synthesis of triazolyl donor/acceptor unnatural C-nucleosides via alkyne (sugar)—azide (aromatic) 1, 3-dipolar cyclo-addition reaction as a key step and studies on their photophysical properties. We have chosen β-1′-ethynyl-2′-deoxyribose as a precursor to synthesize...

In the present study, a series of 2/3-bromo-N′-(substituted benzylidene/3-phenylallylidene)benzohydrazides was synthesized and evaluated in vitro for its antimicrobial and anticancer potentials. The results of antimicrobial and anticancer study indicated that compounds 3, 15 and 18 (pMICam = 1....

Publisher SummaryThis chapter describes the procedure for the assay of the conversion of dethiobiotin to biotin. The mold is grown aerobically for several days on a liquid medium to which a small amount of radioactive d-dethiobiotin is added. Mycelia are filtered off and the filtrate, which cont...

Biotin, analogues, and chemical intermediates were separated by high-performance liquid chromatography (HPLC) using reversed-phase and anion-exchange chromatographic conditions. Reversed-phase separations provided a wide range of retention times and resolution of nearly all the biotin compounds ...

Publisher SummaryBiotin l-sulfoxide occurs in the culture filtrates of various microorganisms. It has been prepared by the oxidation of biotin with 1 mole of hydrogen peroxide and by fractional crystallization of the resulting mixture of biotin d-sulfoxide and biotin l-sulfoxide. It can be prepa...

Rhodobacter sphaeroides f. sp. denitrificans biotin sulfoxide reductase (BSOR) catalyzes the reduction of d-biotin d-sulfoxide to biotin and contains the molybdopterin guanine dinucleotide (MGD) cofactor as its sole prosthetic group. Comparison of the primary sequences of BSOR and the closely re...

d-Biotin, dethiobiotin, d-biotin sulfoxides, and d-biotin sulfone are converted to uv-absorbing or fluorescent derivatives by reaction with ω-4-dibromoacetophenone or 4-bromomethyl methoxy coumarin. High-performance liquid chromatographic separation conditions of these esters are described usin...

Guinea pig aldehyde oxidase was purified about 120-fold at a yield of 26% from liver cytosol by sequential column chromatography using DEAE-cellulose, FMN-Sepharose 4B, and Sephacryl S-300. The purified enzyme showed many similarities with the rabbit liver aldehyde oxidase reported by other work...

Sodium N-chloro-p-toluenesulfonamide (chloramine-T or CAT) is the prominent member of aromatic sulfonyl haloamines and has received considerable attention as a mild oxidant for several organic compounds. d-Biotin, a member of the B-vitamin family, is an essential nutrient in human nutrition as i...