Structural Features of Iperoxo-BQCA Muscarinic Acetylcholine Receptor Hybrid Ligands Determining Subtype Selectivity and Efficacy.

Selective agonists for the human M and M muscarinic acetylcholine receptors (mAChRs) are attractive candidates for the treatment of cognitive disorders, such as Alzheimer's disease and schizophrenia. Past efforts to optimize a ligand for selective agonism at any one of the M-M mAChR subtypes has proven to be a significant challenge. Recently, research efforts have demonstrated that hybrid ligands may offer a potential solution to the lack of selectivity at mAChRs.

Photochemical transformation of a cellulose biosynthesis inhibitor into phytoene desaturase inhibitors.

Mode of action studies showed that 5-methyl-N,N-bis[6-(trifluoromethyl)pyridin-3-yl]pyridin-2-amine (4), a representative from a new class of herbicidal tris-pyridyl amines, is an inhibitor of cellulose biosynthesis (CB). The compound undergoes an oxidative photocyclization, when exposed to UV-B light (300-340 nm) in the presence of oxygen, to give a new class of herbicidal pyrrolodipyridines. These compounds are potent inhibitors of the herbicide target enzyme phytoene desaturase and no longer inhibit CB.