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Updated: Jul 25, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Structure-activity relationship in a series of new 1-(2-pyrimidinyl)piperazine derivatives with hypnotic activity
Z Chilmonczyk1, M Bogdal, M Mazgajska
1Pharmaceutical Research Institute, Warszawa, Poland.
Abstract:
Preparation, biological properties and QSAR of new derivatives of 1-[4-(2-pyrimidinyl)-1-piperazinyl]-1, 3-butandione (11-13, and 15-18) and 3-[4-(2-pirimidinyl)-1-piperazinyl]-3-oxopropanoate (20-22) exhibiting hypnotic activity in mice are reported. The best therapeutic indices (TI = LD50/ED50) 4.7 and 9.4 for po and ip administration, respectively, were found for 1-[4-(2-pyrimidinyl)-1-piperazinyl]-2-n-pentyl-1,3-butandione (15). QSAR studies showed that the biological activity grows initially with an increase in lipophilicity to drop dramatically for log P > 2.5.
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