4490-97-5Relevant academic research and scientific papers
Selective N-acetylation with concurrent S-oxidation of o-amino thiol at ambient conditions over Ce doped ZnO composite nanocrystallites
Jagtap, Rohidas,Sakate, Sachin,Pardeshi, Satish
, p. 19 - 28 (2018/04/27)
The oxidative S–S coupling of thiol to disulfide is an imperative chemical transformation in the domain of biological processes and also finds numerous chemical applications. The CeO2 and ZnO are significant catalysts for oxidation of thiol to disulfide and N-acetylation of amines respectively. Dithiobis(phenylene)bis(benzyldeneimine) moiety containing N-acetyl and disulfide functional groups is a potential antimicrobial agent with Leishmanicidal and antihyperlipidemic activities. Herein, we report a synchronized catalytic application of Ce doped ZnO (Ce-ZnO) and CeO2-Ce-ZnO composites for selective synthesis of Dithiobis(phenylene)bis(benzyldeneimine) from o-amino thiol. The Ce-ZnO samples were synthesized by simple co precipitation method by calcination of hydroxide precursors at 400 °C to get 0–10% Ce-ZnO nanocrystallites. The formation of CeO2-Ce-ZnO composite material was observed beyond 1.5% Ce concentration. The synthesized materials were well characterized by IR, XRD, DRS spectroscopy and SEM-EDS analysis. The application of Ce doped ZnO as an efficient catalyst towards the selective N-acetylation and concurrent S-oxidation of o-amino thiol to afford Dithiobis(phenylene)bis(benzyldeneimine) at ambient temperature in acetonitrile was deliberated. Among all screened catalysts, the maximum selectivity was found for 7.5% Ce-ZnO as CeO2-Ce-ZnO composite catalyst. Lewis acidic property of catalyst supported probable mechanism for achieved dual transformations. Also, the 7.5% Ce-ZnO catalyst has demonstrated a versatile S–S coupling ability for variety of thiol substrates with excellent stability.
Thioacids mediated selective and mild N-acylation of amines
Mali, Sachitanand M.,Bhaisare, Rupal D.,Gopi, Hosahudya N.
, p. 5550 - 5555 (2013/07/25)
N-Acylated amines are ubiquitous in nature. Selective N-acylation at neutral conditions remains a key area of interest. Here we are reporting the copper sulfate-mediated highly selective, mild, and rapid N-acylation of various aliphatic and aromatic amines using thioacids in methanol at neutral conditions. All N-acylated products of primary and secondary amines were isolated in good to excellent yields. This method is found to be highly selective for the amines and not sensitive to other functional groups such as phenols, alcohols, and thiols. The simple workup, high yields, and high selectivity of this reaction can be an attractive alternative to those of the existing acyl halide- and acid anhydride-mediated N-acylation reactions.
Design, syntheses, and characterization of dioxo-molybdenum(vi) complexes with thiolate ligands: Effects of intraligand NH...S hydrogen bonding
Sengar, Raghvendra S.,Miller, Jonathan J.,Basu, Partha
, p. 2569 - 2577 (2008/09/20)
Presence of the hydrogen bonding near a metal center can influence the properties of the complex. Here, we describe changes in redox and spectral properties in discrete dioxo-molybdenum centers coordinated by a single thiolato ligand that can support an intra-ligand hydrogen bond. We have utilized thiophenolato ligands that can harbor hydrogen bonding between the thiophenolato sulfur with an amide functionality creating either a five- or a six-membered ring. Methylation of the amide functionality removes the NH...S hydrogen bonding thus providing a basis for understanding the effect of hydrogen bonding. These thiophenolato ligands have been used in synthesizing dioxo-MoVI complexes of type Tp*MoO2(S-o-RC6H4), where R = CONHMe (11), CONMe2 (12), NHCOMe (13), and N(Me)COMe (14). The complexes have been characterized by NMR, infrared, and UV-visible spectroscopy. Spectroscopic data clearly indicate the presence of hydrogen bonding in both 11 and 13, and stronger in 13, where hydrogen bonding stabilizes a five-membered ring. All complexes exhibit a MoVI/MoV redox couple and redox potentials are modulated by the nature of H-bonding. Compound 14 with the electron-releasing N(Me)COMe group has the highest reduction potential and is more difficult to reduce. The Royal Society of Chemistry.
Solid phase synthesis of benzothiazolyl compounds
Mourtas, Spyros,Gatos, Dimitrios,Barlos, Kleomenis
, p. 2201 - 2204 (2007/10/03)
2-Aminobenzenethiol, bound through its thiol function to the 2-chlorotrityl (Clt)-, trityl (Trt)-, 4-methyltrityl (Mtt)- and 4-methoxytrityl (Mmt)-resins, was acylated at the amino-function by aliphatic and aromatic acids. The obtained 2-N-acyl-aminobenzenethiols were cleaved from the resin by treatment with trifluoroacetic acid solutions in dichloromethane. The 2-N-acyl-aminobenzenethiols released from the resin were cyclised to the corresponding 2-substituted benzothiazoles, by standing in a solution of dithiothreitol in DMF or methanol for 1-3 h at room temperature.
Thermal ring transformation of 2,2-disubstituted benzothiazoline 1- oxides
Shimizu,Kanematsu,Hashimoto,Kobayashi
, p. 73 - 79 (2007/10/03)
Thermal rearrangement of 2,2-disubstituted benzothiazoline 1-oxides (1) in aprotic solvent afforded the corresponding 1,4-benzothiazines (2) and (3). The thermal reaction performed in the presence of electron-deficient acetylenic compounds produced new tricyclic compounds (7) whose structures have been established by an X-Ray crystal structure determination.
Bis(2-(acylamino)phenyl) disulfides, 2-(acylamino)benzenethiols, and S-(2-(acylamino)phenyl) alkanethioates as novel inhibitors of cholesteryl ester transfer protein
Shinkai,Maeda,Yamasaki,Okamoto,Uchida
, p. 3566 - 3572 (2007/10/03)
A series of bis(2-(acylamino)phenyl) disulfides, 2-(acylamino)benzenethiols, S-(2-(acylamino)-phenyl) alkanethioates, and related compounds were synthesized, and their inhibitory effect on cholesteryl ester transfer protein activity in human plasma was evaluated. This study elucidated the structural requirements for inhibitory activity and determined that the optimum compound was S-(2-((1-(2-ethylbutyl)cyclohexane)carbonylamino)phenyl) 2-methylpropanethioate (27) (JTT-705). This compound achieved 50% inhibition of CETP activity in human plasma at a concentration of 9 μM and 95% inhibition of CETP activity in male Japanese white rabbits at an oral dose of 30 mg/kg. It increased the plasma HDL cholesterol level by 27% and 54%, respectively, when given at oral doses of 30 or 100 mg/kg once a day for 3 days to male Japanese white rabbits.
Structure and properties of molybdenum(IV,V) arenethiolates with a neighboring amide group. Significant contribution of NH?S hydrogen bond to the positive shift of redox potential of Mo(V)/Mo(IV)
Ueyama, Norikazu,Okamura, Taka-Aki,Nakamura, Akira
, p. 8129 - 8137 (2007/10/02)
Monooxomolybdenum(V) and monooxomolybdenum(IV) complexes with o-(acylamino)benzenethiolate, (NEt4)[MovO(S-o-RCONHC6H4) 4] (R = CH3, r-Bu, CF3), (NEt4)2[Mos
