A method for separating ALA from ALA derivatives using ionic exchange extraction

Photodynamic therapy using 5-aminolevulinic acid (ALA)-induced protoporphyrin IX is a recent approach to detect and treat some malignancies. The use of lipophilic derivatives of ALA has been exploited in the last years to enhance ALA penetration. In this paper, we describe the application of the Mauzerall and Granick's method [J. Biol. Chem. 219 (1956) 435] to the quantification of ALA derivatives. We also describe the employment of reusable ion-exchange chromatographic columns for separating mixtures of ALA and ALA derivatives present in biological samples. The relation between 555 nm absorbance and ALA or ALA derivative concentration was linear up to 100 nmol/ml and the limit of detection of ALA and ALA derivatives was 1 nmol per ml. We employed a Dowex 50 X8 hydrogen form resin to separate ALA from the derivatives. Whereas 90+/-4% of the total ALA was eluted using sodium acetate, only 3-9% of the ALA derivatives was recovered. Only upon exposure of the resin to a high HCl concentration, the ALA derivatives were completely released. We employed this new method for the separation of ALA from ALA derivatives in cells exposed to different ALA compounds.     

Novel stable fluorophore, 6-methoxy-4-quinolone, with strong fluorescence in wide pH range of aqueous media, and its application as a fluorescent labeling reagent

6-Methoxy-4-quinolone (6-MOQ, 1), an oxidation product derived from 5-methoxyindole-3-acetic acid, is a novel fluorophore, which has several useful characteristics for biomedical analysis. Compound 1 has strong fluorescence with a large Stokes' shift in aqueous media, and the maximum fluorescence excitation and emission wavelengths are 243 nm and 374 nm, respectively. The molar absorptivity at the maximum excitation wavelength and fluorescence quantum yield in aqueous 10% (v/v) methanol are 32 600 L mol(-1) cm(-1) and 0.38, respectively. The fluorescence intensity of 1 is scarcely affected by changing the medium pH, showing strong fluorescence from pH 2.0 to 11.0. In addition, 1 is highly stable against light and heat, and no degradation was observed at 60 degrees C for 3 days with exposure to daylight. As a fluorescent labeling reagent, [(6-methoxy-4-oxo-1,4-dihydroquinolin-3-yl)methyl]amine (6-MOQ-NH2, 2) was synthesized, and determination of carboxylic acids was demonstrated; 50 pmol of standard propionic acid and isobutyric acid were derivatized, and the obtained S/N ratios for 10 fmol (injection amount) of these two acids were 206 and 164, respectively.     

Homopolymers and copolymers of vinyl ethers of rosin-derived alcohols

Two vinyl ethers of rosin-derived alcohols were homopolymerized with free-radical and cationic initiators. A polymer was obtained from the vinyl ether of the alcohol from Foral in good conversion by free-radical initiators but it was not a high molecular weight product. Cationic initiators were more effective; boron trifluoride etherate proved to be best. All of the homopolymers were obtained as white powders with high crystallinity. Copolymerizations of the vinyl ethers and vinyl chloride have been studied with the use of free-radical initiators. Cationic-initiated copolymers of the vinyl ethers and isobutyl vinyl ether were studied. Those containing less than 20% of the rosin vinyl ethers were rubbery, of high molecular weight, and could be crosslinked with peroxide.     

Preparation of furans from alkynols utilizing palladium catalyzed intramolecular addition of alcohol to acetylene as a key reaction

A procedure is described for the synthesis of furans from 3-alkyn-1,2-diols or 2-methoxy-3-alkyn-1-ols by palladium catalyzed intramolecular addition of alcoholic moiety to acetylene linkage followed by elimination of water or methanol. The intermediary 3-furylpalladiums can be trapped with allyl halides affording 3-allylfurans in good yields.     

Glycosides of Atractylodes lancea

Five sesquiterpenoid glycosides (two guaiane-type glycosides and three eudesmane-type glucosides) and a glucoside of an acetylene derivative were newly isolated from the water-soluble portion of the methanolic extract of Atractylodes lancea rhizome together with 26 known compounds. Their structures were characterized as atractyloside A 14-O-beta-D-fructofuranoside, (1S,4S,5S,7R,10S)-10,11,14-trihydroxyguai-3-one 11-O-beta-D-glucopyranoside, (5R,7R,10S)-isopterocarpolone beta-D-glucopyranoside, cis-atractyloside I, (2R,3R,5R,7R,10S)-atractyloside G 2-O-beta-D-glucopyranoside, and (2E,8E)-2,8-decadiene-4,6-diyne-1,10-diol 1-O-beta-D-glucopyranoside on the basis of chemical and spectroscopic investigation. The presence of six characteristic guaiane-type glucosides in both rhizomes of A. lancea and Atractylodes japonica suggested a close chemotaxonomic relationship between them.