TY  - JOUR
A1  - Wieber, Markus
A1  - Fetzer-Kremling, Isa
A1  - Reith, Hildegard
A1  - Burschka, Christian
T1  - Synthese und Struktur von Phenyltetra(acetato)stiboran
T1  - Synthesis and structure of Phenyltetra(acetato)stiborane
N2  - No abstract available
KW  - Chemie
KW  - Phenyltetra(acetato)stiborane
KW  - Synthesis
KW  - X-Ray Crystal Structure
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47137
ER  - 
TY  - JOUR
A1  - Wieber, Markus
A1  - Lang, Stefan
A1  - Rohse, Stefan
A1  - Habersack, Ralph
A1  - Burschka, Christian
T1  - Synthese und Kristallstruktur von Triphenyltelluroniumsulfid
T1  - Synthesis and Crystal Structure of Triphenyltelluroniumsulfide
N2  - No abstract available
KW  - Chemie
KW  - Triphenyltelluroniumsulfide
KW  - Synthesis
KW  - NMR Data
KW  - Crystal Structure
KW  - Secondary Bonding
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47151
ER  - 
TY  - JOUR
A1  - Darwish, Hany W.
A1  - Attia, Mohamed I.
T1  - New spectrofluorimetric methods for determination of melatonin in the presence of N-{2-[1-({3-[2-(acetylamino)ethyl]-5-methoxy-1H-indol-2-yl}methyl)-5-methoxy-1H-indol-3-yl]- ethyl}acetamide: a contaminant in commercial melatonin preparations
N2  - Background: Melatonin (MLT) has many health implications, therefore it is of valuable importance to develop specific analytical methods for determination of MLT in the presence of its main contaminant, N-{2-[1-({3-[2-(acetylamino)ethyl]-5-methoxy-1H-indol-2-yl}methyl)-5-methoxy-1H-indol-3-yl]ethyl}acetamide (10). For development of these analytical methods, compound 10 had to be prepared in an adequate amount. Results: Compound 10 was synthesized in six steps starting from 5-methoxyindole-2-carboxylic acid (1). Analytical performance of the proposed spectrofluorimetric methods was statistically validated with respect to linearity, accuracy, precision and specificity. The proposed methods were successfully applied for the assay of MLT in laboratory prepared mixtures containing up to 60 % of compound 10 and in commercial MLT tablets with recoveries not less than 99.00 %. No interference was observed from common pharmaceutical additives and the results were favorably compared with those obtained by a reference method. Conclusions: This work describes simple, sensitive, and reliable second derivative spectrofluorimetric method in addition to two multivariate calibration methods, principal component regression (PCR) and partial least square (PLS), for the determination of MLT in the presence of compound 10.
KW  - Chemie
KW  - Melatonin
KW  - Contaminants
KW  - Synthesis
KW  - Spectrofluorimetry
KW  - Commercial preparations
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78234
ER  -