21235-63-2Relevant articles and documents
Stereoselective Synthesis of Vinylboronates by Rh-Catalyzed Borylation of Stereoisomeric Mixtures
Li, Shenhuan,Li, Jie,Xia, Tianlai,Zhao, Wanxiang
supporting information, p. 462 - 468 (2019/03/28)
The stereoselective preparation of vinylboronates via rhodium-catalyzed borylation of E/Z mixtures of vinyl actetates is described, and this method was also extended to synthesis of vinyldiboronates. These transformations feature high functional group compatibility and mild reaction conditions. Control experiments support a mechanism that involved a Rh-catalyzed borylation-isomerization sequence. The isomerization of (Z)-vinylboronates to (E)-isomers was also demonstrated.
N-Propynyl analogs of β-phenylethylidenehydrazines: Synthesis and evaluation of effects on glycine, GABA, and monoamine oxidase
MacKenzie, Erin M.,Fassihi, Afshin,Davood, Asghar,Chen, Qiao-Hong,Rauw, Gillian,Rauw, Gail,Knaus, Edward E.,Baker, Glen B.
experimental part, p. 8254 - 8263 (2009/04/07)
A group of β-phenylethylidenehydrazines possessing a variety of substituents (Me, OMe, Cl, F, and CF3) at the ortho-, meta-, or para-positions of the phenyl ring, in conjunction with either a N-bis-(2-propynyl) or a N-mono-(2-propynyl) moiety, were synthesized and compared to the novel neuroprotective drug β-phenylethylidenehydrazine (PEH) with regard to their ability to inhibit the enzymes GABA-transaminase (GABA-T) and monoamine oxidase (MAO)-A and -B in vitro in brain tissue. Two of the analogs synthesized (mono- and bis-N-propynylPEH) were also studied ex vivo in rats to compare their effects to those of PEH with regard to ability to inhibit GABA-T and MAO and to change brain levels of several important amino acids. Unlike PEH, none of the new drugs inhibited GABA-T in vitro at 10 or 100 μM, and all of the drugs (including PEH) were poor inhibitors (at 10 μM) of MAO-A and -B in vitro. The two analogs studied ex vivo inhibited GABA-T to a lesser extent than PEH, unlike PEH that did not elevate brain levels of GABA, and inhibited MAO-A and -B more potently than PEH. Interestingly, unlike PEH, the two analogs caused marked increases in brain levels of glycine; because of the current interest in drugs that increase glycine availability in the brain as potential antipsychotic drugs, these two analogs now warrant further investigation.
Design and biological evaluation of phenyl-substituted analogs of β-phenylethylidenehydrazine
Sowa, Bernard,Rauw, Gillian,Davood, Asghar,Fassihi, Afshin,Knaus, Edward E.,Baker, Glen B.
, p. 4389 - 4395 (2007/10/03)
β-Phenylethylidenehydrazine (PEH) has been demonstrated previously to be an inhibitor of γ-aminobutyric acid transaminase (GABA-T) and to cause a marked increase in rat brain levels of GABA, a major neurotransmitter. A group of PEH analogs, possessing a variety of substituents (Me, OMe, Cl, F, and CF3) at the 2-, 3-, and 4-positions of the phenyl ring, were synthesized for evaluation as inhibitors of GABA-T. The details of the synthesis and chemical characterization of the analogs are described. Preliminary in vitro screening for GABA-T inhibition showed that all the analogs possessed activity against this enzyme, although substitution of CF3 at the 2- and 4-positions caused reduced activity. One of the drugs, 4-fluoro-β- phenylethylidenehydrazine, was investigated further ex vivo, where it was shown to inhibit GABA-T, elevate brain levels of GABA, and decrease levels of glutamine, similar to the profile observed previously for PEH.
