255723-98-9Relevant academic research and scientific papers
Efficient one-pot synthesis of enantiomerically pure: N -protected-α-substituted piperazines from readily available α-amino acids
Jida, Mouhamad,Ballet, Steven
, p. 1595 - 1599 (2018/02/09)
A new pathway towards enantiomerically pure 3-substituted piperazines, bearing a benzyl protecting group, has been developed in good overall yields (83-92%), starting from commercially available N-protected amino acids. The methodology represents an efficient and simple one-pot procedure, employing a synthetic sequence consisting of an Ugi-4 component reaction, a Boc-deprotection, an intramolecular cyclisation reaction and a final reduction (UDCR). From the benzyl protected precursors, the 2-substituted piperazines bearing a Boc-protecting group could consequently also be obtained via a simple protection and deprotection step of the corresponding piperazines. The practical utility of this methodology was demonstrated for chiral drug synthesis.
Exploring the structure-activity relationships of [1-(4-(4- tert-butyl-3'-hydroxy)benzhydryl-4-benzylpiperazine] (SL-3111), a high-affinity and selective δ-opioid receptor nonpeptide agonist ligand
Alfaro-Lopez, Josue,Okayama, Toru,Hosohata, Keiko,Davis, Peg,Porreca, Frank,Yamamura, Henry I.,Hruby, Victor J.
, p. 5359 - 5368 (2007/10/03)
SL-3111 [1-(4-tert-butyl-3'-hydroxy)benzhydryl-4- benzylpiperazine] is a de novo designed, high-affinity and selective nonpeptide peptidomimetic agonist of the δ-opioid receptor. In a previous report we had described the unique biological characteristics of this ligand and also a need for further structural evaluation. To pursue this, we have introduced a completely different heterocyclic template (2 and 3), which, based on molecular modeling studies, may present the required structural features to properly orient the pharmacophore groups. We also have made more subtle changes to the original piperazine scaffold (5 and 11). The biological activities of these compounds revealed an important participation of the scaffold in the ligand-receptor interaction. To further explore functional diversity on the scaffold, we have maintained the original piperazine ring and introduced four different functionalities at position 2 of the heterocyclic ring (15a-d; a = CH2-O-CH2-Ph; b = Me; c = CH2Ph; d = CH2OH). The biological activities observed for these compounds showed a very interesting trend in terms of the steric effects of the groups introduced at this position. A decrease of almost 2000-fold in affinity and potency at the δ- receptor was observed for 15c compared with 15b. This difference may be explained if we postulate that the bioactive conformation of these peptidomimetics is close to the minimal energy conformations calculated in our study. On the basis of these findings we have realized the importance of this position to further explore and simplify the structure of future generations of peptidomimetic ligands.
