PubMed · 1389613
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
N Sarker. 1992-09-19. 'Alternatives to toothpaste'.. https://doi.org/10.1038/sj.bdj.4807981
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
Quantitative structure-activity relationship (QSAR) analyses of three different series of benzodiazepine ligands, pyridodiindoles, and beta-carbolines, having inverse agonist/antagonist and agonist actions have been performed with a view to understanding their likely mode of action at the benzodiazepine-receptor (BzR). From this study, the in vitro radioligand displacement activities of substituted 7,12-dihydropyrido[3,2-b: 5,4-b']diindoles (Figure 1) were found to be significantly correlated with resonance effect of R-substituents, van der Waals volumes at positions-1 and -3, hydrophobic constant at position-2 and field effect at position-4 of X-substituents. For 3-substituted beta-carbolines, a similar analysis has established that R-substituents at position-3 of beta-carbolines (Figure 2) are involved in strong hydrophobic interaction with some hydrophobic pocket on the receptor. For the analogues of 6-(benzyloxy)-4-(methoxymethyl)-beta-carbolines-3-carboxylic acid ethyl ester (Figure 3), however, the combined hydrophobicities of 6- and 4-substituents were shown to be important in determining ligand binding behaviour. The significant correlations so obtained are in agreement with the proposed models (Figures 4 and 5) of pharmacophores of inverse agonist/antagonist and of agonist sites at the BzR.
For evaluation of the cancer risk by the tryptophan pyrolysates a sensitive enzyme immunoassay for 3-amino-1-methyl-5H-pyrido-[4,3-b]indole (Trp-P-2), a mutagenic and carcinogenic substance, found in foods and biological fluids has been developed. The dose-response curve obtained was suitable for the determination of Trp-P-2 in the range of 20-800 pg. The immunoassay system was characterized to be satisfactorily specific as judged by cross-reactivity to gamma-carboline derivatives and their precursors, and comparison of immunoreactive Trp-P-2 levels in the basic and neutral fraction derived from pyrolyzed amino acids and related compounds.