Compound 1 obtained by random screening and displaying a micromolar activity on the mu opiate receptor was chosen as a starting point for optimization. Two complementary concepts of similarity were used for the design of analogues and compared. These are based, respectively, on a computer-aided comparison of pharmacophoric patterns and on topological similarity. The structure-activity relationships are discussed in light of both similarity concepts. Compound 40, an N-methyl-3-(4-oxo-1-phenyl-1,3,8-triazaspiro[4.5]decyl)acetamide derivative, designed by combining the structure-activity relationships enlightened by each method, has a subnanomolar affinity for mu (h) receptor (IC(50) = 0.9 nM). It is a promising lead, allowing the design of a new series of analogues substituted at the N-3 of the spirocycle moiety.
A novel mitochondria-localizing nitrobenzene derivative as a donor for photo-uncaging of nitric oxide
We report a novel green-fluorescent NO donor, NBDNO, bearing a 2,6-dimethylnitrobenzene moiety for photocontrollable NO release and a triphenylphosphonium moiety for targeting to mitochondria. Photorelease of NO from NBDNO was confirmed by means of ESR analysis in aqueous solution. Intracellular release of NO from NBDNO was confirmed by using DAR-4M AM, an NO-specific fluorescence probe. NBDNO was