The quantitative isolation of total glycosphingolipids from crude lipid extracts without contamination from other lipid classes is described. The method consists of (a) acetylation of total lipids with pyridine and acetic anhydride, (b) separation of acetylated glycolipids from nonglycolipids on a magnesia-silica gel (Florisil) column, and (c) deacetylation of glycolipid in chloroform-methanol-...

On direct comparison by TLC and IR we established that the alkaloids A-5 and A-4, first isolated from Vinca herbacea W. K . 1 are identical to the oxindole alkaloid majdine (I), later isolated from Vinca major L. 2' 3 and with its isomer isomajdine (II), prepared by heating of (I) in acetic anhydride 2. Based upon some spectroscopic evidence it was claimed2, that majdine was a diastereomer of c...

The physical properties of rat liver chromatin and nucleosomes acetylated with acetic anhydride were examined in order to clarify the mechanism by which chemical acetylation of histones increases template activity in vitro [Marushige, K. (1976) Proc. Natl. Acad. Sci. USA 73, 3937-3941]. Acetylation was found to have dramatic effects on the magnesium solubility, nuclease sensitivity, thermal den...

An efficient synthetic route to prepare O -(2- -benzyl-3,4-di- -acetyl-?/?- l -fucopyranosyl)-trichloroacetimidate from -fucose was developed by introducing the thiophenyl group at anomeric center and benzylidene functional protect 3 4 positions. Although three approaches were considered, best result obtained when, after 2-hydroxyl benzylation, both protective groups simultaneously removed usin...

The synthesis of N-acetyl derivatives of α-amino acids (L–Gly, L–Val, L–Phe, L–Ile, L–Pro and L–Cys) using a simple and efficient method for preparation was carried out. The N-acetyl derivatives were obtained using acetic anhydride in basic conditions at room temperature. The methyl amides of N–acetyl amino acid were synthesized by mixed anhydride procedure using a Piv–Cl as a reagent. The conv...

We studied unsupported VxOy nanoparticles prepared by a novel non-aqueous route in the selective oxidation of n-butane to maleic anhydride. The evolution of the electronic and geometric structure of the material was characterized by X-ray photoemission spectroscopy, electron energyloss spectroscopy, transmission electron microscopy and electron diffraction before and after the reaction at diffe...

Reactions of 4-hydroxycoumarin 1 with heterocyclic aldehydes 2-4 led to bis-4-hydroxycoumarin derivatives 5-7 under microwave irradiation as well the classical heating. The subsequent reactions products are described. 4,4’-Epoxydicoumarins 8, 9 were prepared by reaction in acetic acid / p-toluenesulfonic medium. Compound 10 was 5 anhydride presence sodium acetate. Dioxocine-1,15-dione 11 6 dich...

Flow injection analysis coupled with membrane introduction mass spectrometry (FIA-MIMS) with on-line derivatization is shown to allow fast, accurate, nearly interference-free, and sensitive (low microgram/L) quantitation of phenolic compounds in water. On-line FIA derivatization of the phenolic compounds is performed by acetic anhydride acetylation in a K2CO3-buffered alkaline medium. The pheno...