32338-22-0Relevant articles and documents
One-Pot Generation of Benzynes from Phenols: Formation of Primary Anilines by the Deoxyamination of Phenols
Akai, Shuji,Ikawa, Takashi,Masuda, Shigeaki
, (2020/03/23)
Benzynes were selectively generated in situ from phenols and trapped regioselectively with potassium hexamethyldisilazide to form primary anilines following acidic workup. The direct conversion of a phenolic hydroxyl group into a free amino group is a useful method for the preparation of primary aryl amines that are hard to synthesize by using coupling reactions involving phenol derivatives with ammonia. Whereas reactions of ortho- and meta-substituted phenols produced meta-substituted anilines exclusively, those of para-substituted phenols provided ortho-silylanilines.
Photoswitchable thioureas for the external manipulation of catalytic activity
Osorio-Planes, Laura,Rodriguez-Escrich, Carles,Pericas, Miquel A.
supporting information, p. 1704 - 1707 (2014/04/17)
A series of azobenzene-based thiourea catalysts have been developed with the aim of achieving control over the catalytic activity by the use of light. The conceptual design of these systems relies on the inactivation by means of intramolecular hydrogen bonding, only likely to take place in one of their isomeric forms. After fine structure modulation of the catalyst a substantial difference in activity has been observed between the irradiated and the nonirradiated reaction. Furthermore, the system allowed in situ manipulation of the catalyst activity during the course of a given experiment.
Helical conformational dynamics and photoisomerism of alternating pyridinedicarboxamide/m-(phenylazo)azobenzene oligomers
Tie, Chenyang,Gallucci, Judith C.,Parquette, Jon R.
, p. 1162 - 1171 (2007/10/03)
Alternating sequences of pyridine-2,6-dicarboxamides and meta-(phenylazo)azobenzenes have been assembled into oligomers composed of four (8) and eight (9) azobenzene linkages. X-ray crystallography confirmed that oligomer 8 adopts a two-turn helical conformation with a helical pitch of approximately 3.4 A in the solid state. The presence of a two- and four-turn helical conformation of 8 and 9, respectively, in polar and nonpolar solvents was elucidated by the anisotropic upfield shifting of protons located within the helices, NOE enhancements between protons oriented toward the helix interior, and the diastereotopicity of the terminal benzyloxycarbonyl (CBz) methylene protons. 1H NMR line shape analysis of the CBz methylene hydrogens at the chain ends revealed a dynamic equilibria interconverting M and P helical conformations with energetic barriers (ΔG?) of 11.1 (ΔS? = -19.4 ± 1.6 cal mol-1 K-1; ΔH? = 6.5 ± 0.4 kcal/mol) for 8 and 13.8 kcal/mol (ΔS? = -6.6 ± 6.2 cal mol -1 K-1; ΔH? = 11.8 ± 1.8 kcal/mol) for 9. Irradiation of the oligomers with 350 nm light induces an E → Z isomerization of the azo linkages that decreases in efficacy at longer helix lengths. The suppression of E -Z isomerization is a consequence of the contrasting behavior of the azo linkages located at the helix termini, which afford ZIE ratios similar to those of model compound 7d, and the internal azo groups, which undergo significantly lower ZIEconversion ratios compared with 7e.
Synthesis and anticonvulsant and neurotoxic properties of substituted N- phenyl derivatives of the phthalimide pharmacophore
Vamecq, Joseph,Bac, Pierre,Herrenknecht, Christine,Maurois, Pierre,Delcourt, Philippe,Stables, James P.
, p. 1311 - 1319 (2007/10/03)
A series of compounds including 4-amino (1), 3-amino (2), 4-nitro (3), 2-methyl-3-amino (4), 2-methyl-3-nitro (5), 2-methyl-4-amino (6), 2-methyl-4- nitro (7), 2-methyl-5-amino (8), 2-methyl-5-nitro (9), 2-methyl-6-amino (10), 2-methyl-6-mitro (11), 2,6-dimethyl (12), 2-methyl-3-carboxy (13), 2- methoxycarbonyl (14), 2-methyl-4-methoxy (15), 2,4-dimethoxy (16), 2-chloro- 4-amino (17), and 2-chloro-4-nitro (18) N-phenyl substituents of phthalimide were evaluated along with N-[3-methyl-(2-pyridinyl)]phthalimide (19), N-(3- amino-2-methylphenyl)succinimide (20), and phenytoin for anticonvulsant and neurotoxic properties. Initial screening in the intraperitoneal (ip) maximal electroshock-induced seizure (MES) test and the subcutaneous pentylenetetrazol-induced seizure (scPtz) test in mice led to the selection of 1, 2, 4, 10, 12, 17, and 19 for oral MES evaluation in rats. The resultant ED50 values for 4, 10, 17, and phenytoin were 8.0, 28.3, 5.7 and 29.8 mg/kg, respectively. In the batrachotoxin affinity assay, IC50 values for 17 and phenytoin were 0.15 and 0.93 μM, respectively, and in the recently validated magnesium deficiency-dependent audiogenic seizure test, ED50 values of 5.2 and 23 mg/kg were obtained for 17 and phenytoin, respectively. Electrophysiology studies on compound 17 point out its ability to (i) potentiate GABA-evoked current responses with a failure to directly activate the GABAA receptor and (ii) to affect, at 100 μM excitatory non NMDA, but not NMDA, receptors with a 25% block of kainate-evoked response. Electrophysiology measurements on voltagegated sodium channels in N1E-115 neuroblastoma cells confirm voltage-dependent block of these channels by compound 17. In view of its interaction with multiple ion channels, one would predict that compound 17 might be active in a wide range of seizure models.
