2038-01-9Relevant academic research and scientific papers
The synthesis of cyclic and acyclic long-chain arylpiperazine derivatives of salicylamide as serotonin receptor ligands
Kowalski, Piotr,Jaskowska, Jolanta,Bojarski, Andrzej J.,Duszynska, Beata
, p. 209 - 214 (2008/09/18)
(Chemical Equation Presented) The 1-arylpiperazine series of N-substituted 1,3-benzoxazine-2,4-diones as well as O- and N-substituted salicylamides with an n-propyl chain were synthesized in order to explore the effect of cyclic and acyclic salicylamide moieties on their binding affinity for 5-HT1A, 5-HT2A and 5-HT7 receptor sites. Target compounds 1 and 2 were prepared by a two-step procedure, i.e. by alkylation of 1,3-benzoxazine-2,4-dione or salicylamide with 1,3-dibromopropane and next by condensation of 3-bromopropyl intermediates with arylpiperazines; syntheses of 3-bromopropyl intermediates were performed in solvent-free conditions. Compounds 3 were prepared by hydrolysis of 1. In respect of salicylamide moieties, binding affinities for 5-HT1A and 5-HT7 receptors increase according to the rank of derivatives 3 2A receptors, increased activity of ligands was changed in reverse order to the affinity for 5-HT1A, i.e. 2 1A and 5-HT7 receptor binding constants were the highest for the 2-methoxyphenyl ligand 2c, while the 3-chlorophenyl ligand 3b was most active for 5-HT2A receptors.
N-alkylation of imides using phase transfer catalysts under solvent-free conditions
Jaskowska, Jolanta,Kowalski, Piotr
experimental part, p. 1371 - 1375 (2009/04/07)
(Chemical Equation Presented) N-Alkylation of imides in the reaction of imides and alkylhalides, catalyzed by PT catalysts under solvent-free conditions, has been developed. The reaction occurs in the presence of K 2CO3, and in many cases it takes place spontaneously. In the N-benzylation reaction, it has been recognized that TBAB (tetrabutylammonium bromide) and TBATFB (tetrabutylammonium tetrafluoroborate) show highest catalytic effect. Versatility and synthetic capacity of the solvent-free alkylation has been confirmed by N-benzylation and N-ethylation of various imides. The developed procedure gives easy access to N-(ω-bromoalkyl) imides.
