1,3-Bis[2-hy-droxy-2-(6-meth-oxy-2,2-dimethyl-3a,5,6,6a-tetra-hydro-2H-furo[2,3-d][1,3]dioxol-5-yl)eth-yl]-2,3-dihydro-1H-1,3-benzodiazol-2-one.

In the title benzimidazolone, C(27)H(38)N(2)O(11), which has N-bound glycosidic units, all five-membered O-heterocyclic rings adopt envelope conformations [for the outer rings, the C atom with the dimethyl groups represents the flap atom]. The two glycosidic units are related by a non-crystallographic twofold rotation axis that passes through the carbonyl portion. In the mol-ecular structure, the hy-droxy groups are hydrogen-bond donors to the carbonyl O atom. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

2-Hy-droxy-2,3,5,10,11,11a-hexa-hydro-1H-pyrrolo-[2,1-c][1,4]benzodiazepine-5,11-dione.

The seven-membered ring of the title compound, C(12)H(12)N(2)O(3), which is fused with the phenyl-ene ring, adopts a boat-shaped conformation (with the methine C atom as the prow and the phenyl-ene C atoms as the stern); the H atom on the methine linkage exists in an axial position. The five-membered ring that is fused with the seven-membered ring adopts an envelope conformation (with the C atom bearing the hy-droxy substituent representing the flap) [the deviation from the plane defined by the other four atoms is 0.200 (7) Šin one mol-ecule and 0.627 (5) Šin the other]. The two independent mol-ecules are disposed about a pseudo center of inversion and are connected by a pair of N-H⋯O hydrogen bonds. Adjacent dimers are linked by a pair of O-H⋯O hydrogen bonds, generating a chain running along the b axis.

Electrospray tandem mass spectrometric analysis of novel synthetic quinoxalinone derivatives.

Electrospray ionization tandem mass spectrometry (ESI-MS/MS) using a hybrid QqToF-MS/MS instrument has aided the structural characterization and differentiation of a novel series of medicinal synthetic 1-N-glycoside-quinoxalinone derivatives. These derivatives 7 and 8 are formed by an amino bond between the cyclic N-1 of the quinoxaline moiety and the C-6 position of a fully protected methyl or allyl alpha-D-mannofuranoside 3 and 4, and subsequent deprotection of the mannopyranoside moiety. In general the novel synthetic quinoxaline derivatives afforded the protonated molecules in ESI. The breakdown routes of the protonated molecules were rationalized by conducting low-energy CID-MS/MS analyses. In addition, re-confirmation of the various established fragmentation routes was achieved by conducting a series of ESI-CID-QqTof-MS/MS product ion scans on various selected precursor ions, which were initiated by CID in the atmospheric pressure/vacuum interface using a higher declustering potential. ESI-QqToF-MS/MS analysis has proven to be a specific and very sensitive method for the structural identification in the gas phase of these novel glycoquinoxalinamine derivatives.

Towards the synthesis of new benzimidazolone derivatives with surfactant properties.

New water-soluble benzimidazolone derivatives were synthesized. In the first approach, di-N-glycosyl and mono-N-alkyl-N-glycosyl compounds were obtained by grafting C-6-activated glycosides onto benzimidazolone. In the second approach, benzimidazolone derivatives bearing a glucosyl unit were synthesized using an efficient glycosylation method. Every compound structure was confirmed by means of NMR spectroscopy and elemental analysis. The preliminary surfactant properties of some compounds were evaluated.

Structural determination of the novel fragmentation routes of zwitteronic morphine opiate antagonists naloxonazine and naloxone hydrochlorides using electrospray ionization tandem mass spectrometry.

Electrospray ionization quadrupole time-of-flight (ESI-QqToF) mass spectra of the zwitteronic salts naloxonazine dihydrochloride 1 and naloxone hydrochloride 2, a common series of morphine opiate receptor antagonists, were recorded using different declustering potentials. The singly charged ion [M+H-2HCl](+) at m/z 651.3170 and the doubly charged ion [M+2H-2HCl](2+) at m/z 326.1700 were noted for naloxonazine dihydrochloride 1; and the singly charged ion [M+H-HCl](+) at m/z 328.1541 was observed for naloxone hydrochloride 2. Low-energy collision-induced dissociation tandem mass spectrometry (CID-MS/MS) experiments established the fragmentation routes of these compounds. In addition to the characteristic diagnostic product ions obtained, we noticed the formation of a series of radical product ions for the zwitteronic compounds 1 and 2, and also the formation of a distonic ion product formed from the singly charged ion [M+H-HCl](+) of naloxone hydrochloride 2. Confirmation of the various established fragmentation routes was effected by conducting a series of ESI-CID-QqTof-MS/MS product ion scans, which were initiated by CID in the atmospheric pressure/vacuum interface using a higher declustering potential. Deuterium labeling was also performed on the zwitteronic salts 1 and 2, in which the hydrogen atoms of the OH and NH groups were exchanged with deuterium atoms. Low-energy CID-QqTof-MS/MS product ion scans of the singly charged and doubly charged deuteriated molecules confirmed the initial fragmentation patterns proposed for the protonated molecules. Precursor ion scan analyses were also performed with a conventional quadrupole-hexapole-quadrupole tandem mass spectrometer and allowed the confirmation of the genesis of some diagnostic ions.