Synthesis, characterization and antibacterial susceptibility testing of manganese complexes of doxycyline with bipyridine and phenanthroline

Three manganese complexes of the antibiotic doxycyline viz.: manganese doxycyline, [MnDox2]Cl2‧2H2O (1), and manganese doxycyline with bipyridine, [MnDox2(bpy)]Cl2‧8H2O (2), and phenanthroline, [MnDox2(phen)]Cl2‧8H2O (3), as the ancillary ligand were synthesized and characterized by FT-IR, elemental analysis and electrospray mass spectroscopy. The three complexes show good solubility in DMF and DMSO. Data obtained from spectroscopic techniques used show that doxycycline coordinates to the central manganese atom through the oxygen of the amide group and the carbonyl oxygen atom of ring A while bipyridine/phenanthroline coordinates through the two diimine nitrogen atoms. The stoichiometry of manganese-doxycycline is 1:2 and octahedral geometry is the preferred coordination in all the complexes.

Synthesis and Application of Reactive Dyes Containing a Hydroxybenzophenone Ultraviolet Absorber

Novel orange reactive dyes containing a built-in benzophenone moiety had been synthesized in four steps and characterized using electrospray mass spectroscopy analysis. They were applied to dye cotton fabrics and evaluated for their ability to give protection against the harmful UV radiation. The results showed that the anti-ultraviolet properties of the dyed cotton with the dyes containing a built-in hydroxybenzophenone moiety were significantly improved. However, the incorporation of methyl or ethyl groups into the benzophenone moiety did not show a beneficial effect on the UPF values of dyed cotton.

A novel crown ether generation containing the pyrilium heteroaromatic cation — Synthesis, characterization, and solid-phase 13C NMR

The synthesis and structural characterization of two members, 5 and 6, of a novel generation of crown ethers containing the pyrilium cation are reported. These two compounds contain two and three benzo-9-crown-3 (B9C3) units, respectively, connected to the 2 and 6 or 2, 4, and 6 positions of a central pyrilium cation. The crown ethers 5 and 6 were obtained from the condensation reaction of appropriate aldehydes and methyl ketones in the presence of POCl3. A variety of physicochemical methods including electrospray mass spectroscopy, solution 1H and 13C NMR, and solid-phase 13C NMR were applied for structural characterization. The 1H and 13C NMR studies indicate rapid rotation of the B9C3 unit about the C–C bond that connects the two units to each other. The solid-phase 13C NMR spectra of these two crown ethers reveal that there are deviations from planarity for the two phenyl rings attached at the 2 and 6 positions of the central pyrilium cation.Key words: crown ether, pyrilium, solid-phase NMR, crownpyrilium, heteroaromatic.

A Novel Acetylated 3-Deoxyanthocyanidin Laminaribioside from the Fern Blechnum novae-zelandiae

The major 3-deoxyanthocyanin isolated from the fern Blechnum novae-zelandiae was de­termined to be luteolinidin 5-O-β-ᴅ-[3-O-β-ᴅ-glucopyranosyl-2-O-acetylglucopyranoside] and was found to co-occur with quercetin 3-O-β-ᴅ-[6-O-caffeoylglucopyranoside], quercetin 3-O-β-ᴅ-[6-O-caffeoylgalactopyranoside] and kaempferol 3-O-β-ᴅ-glucuronopyranoside. These pigments were identified by using HPLC chromatography, NMR (1ᴅ , 2ᴅ) and electrospray mass spectroscopy.

Attenuated Nontoxinogenic and Nonencapsulated Recombinant Bacillus anthracis Spore Vaccines Protect against Anthrax

ABSTRACT Several highly attenuated spore-forming nontoxinogenic and nonencapsulated Bacillus anthracis vaccines differing in levels of expression of recombinant protective antigen (rPA) were constructed. Biochemical analyses (including electrospray mass spectroscopy and N terminus amino acid sequencing) as well as biological and immunological tests demonstrated that the rPA retains the characteristics of native PA. A single immunization of guinea pigs with 5 × 107 spores of one of these recombinant strains, MASC-10, expressing high levels of rPA (≥100 μg/ml) from a constitutive heterologous promoter induced high titers of neutralizing anti-PA antibodies. This immune response was long lasting (at least 12 months) and provided protection against a lethal challenge of virulent (Vollum) anthrax spores. The recombinant B. anthracis spore vaccine appears to be more efficacious than the vegetative cell vaccine. Furthermore, while results clearly suggest a direct correlation between the level of expression of PA and the potency of the vaccine, they also suggest that some B. anthracisspore-associated antigen(s) may contribute in a significant manner to protective immunity.