Regioselective preparation and NMR spectroscopy study of 2-chloro-4-ethoxy-quinoline for the synthesis of 2-((3-aminopropyl)amino)quinolin-4(1H)-one.

Herein, we describe the C4-ethoxylation of 2,4-dichloroquinoline to prepare 2-chloro-4-ethoxy-quinoline (3), which is a prominent intermediate used for the synthesis of 2-substituted quinolones. To achieve this goal, we studied different conditions for the reaction between 2,4-dichloroquinoline and sodium ethoxide. We discovered that the use of 18-crown-6 ether as an additive and dimethylformamide as the reaction solvent allowed us to obtain the desired product 3 in very good yield and selectivity.

Novel series of tacrine-tianeptine hybrids: Synthesis, cholinesterase inhibitory activity, S100B secretion and a molecular modeling approach.

Tianeptine was linked to various 9-aminoalkylamino-1,2,3,4-tetrahydroacridines using EDC·HCl/HOBt to afford a series of tacrine-tianeptine hybrids. The hybrids were tested for their ability to inhibit AChE and BuChE and IC50 values in the nanomolar concentration scale were obtained. AChE molecular modeling studies of these hybrids indicated that tacrine moiety interacts in the bottom of the gorge with the catalytic active site (CAS) while tianeptine binds to peripheral anionic site (PAS).