- Synthesis of 1-Alkyl-5-amino-1,2,4-triazoles Based on Nucleophilic Substitution and Reduction Reactions
-
A series of 1-alkyl-5-amino-1H-1,2,4-triazoles were synthesized starting from 3,5-dibromo-1H- 1,2,4-triazole by alkylation and subsequent nucleophilic substitution of the 5-bromine atom by azido group, reduction of the latter to amino group, and hydrodebromination.
- Tolstyakov
-
p. 1537 - 1547
(2019/01/04)
-
- Reinvestigating Raney nickel mediated selective alkylation of amines with alcohols via hydrogen autotransfer methodology
-
An efficient, cost-effective use of Raney nickel (R-Ni) a widely used industrial catalyst for N-alkylation using alcohols is highlighted here. The work describes the scope and capability of R-Ni in hydrogen autotransfer reactions enabling its widespread use in the Chemical and Pharmaceutical industry. R-Ni of W4, T4, and W7 grades were prepared and evaluated for alkylation of amines. The best activity and selectivity for mono alkylation of amines were obtained using W4 R-Ni at 1:4 moles of amine to alcohol in xylene at reflux. T4 R-Ni also showed ability to form stable imines. The prepared R-Ni was also recycled and reused for N-alkylation reaction. The optimized methodology was applied for synthesis of Active Pharmaceutical ingredients Piribedil and Mepyramine. The simplicity and wide substrate scope makes this method a preferred Hydrogen Auto-transfer protocol for the alkylation of amines.
- Mehta, Astha,Thaker,Londhe,Nandan, Santosh R.
-
p. 241 - 251
(2014/05/20)
-
- TRIAZOLE COMPOUNDS AND THEIR USE AS GAMMA SECRETASE MODULATORS
-
The present invention relates to compounds of formula (I) and pharmaceutically acceptable salts thereof. The invention also relates to pharmaceutical compositions comprising these compounds, to processes for making these compounds, and to their use as medicaments for treatment and/or prevention of Αβ-related diseases.
- -
-
Page/Page column 17; 18
(2015/01/06)
-
- Microemulsion technique for the novel synthesis of deferasirox using metal mediated coupling
-
A novel and efficient synthesis of Deferasirox has been accomplished using transition metal catalyzed sequential cross coupling reactions. First stage of the synthesis employs the use of Chan-Lam coupling between 3,5-dibromo-1H[1,2,4] triazole and (4-(methoxycarbonyl)-phenyl)boronic acid to give methyl 4-(3,5-dibromo-1H-1,2,4-triazol-1-yl)benzoate which is further elaboarated to Deferasirox by Suzuki-Miyaura coupling with 2-hydroxyphenyl-boronic acid pinacol ester in microemlusion.
- Roy, Bhairab Nath,Singh, Girij Pal,George, Shaji K.,Lathi, Piyush S.,Agrawal, Manoj K.,Trivedi, Anurag,Mishra, Madhan,Singh, Gajendra
-
p. 610 - 618
(2014/06/23)
-
- The first versatile synthesis of 1-alkyl-3-fluoro-1H-[1,2,4]triazoles
-
Reaction of 1-benzyl-3,5-dibromo-1H-[1,2,4]triazole (3) with cesium fluoride yielded selectively 1-benzyl-3-bromo-5-fluoro-1H-[1,2,4]triazole (4). Debenzylation and realkylation afforded 1-alkyl-5-bromo-3-fluoro-1H-[1,2,4]triazoles 7, which reacted with a wide variety of nucleophiles to give 5-substituted 1-alkyl-3-fluoro-1H-[1,2,4]triazoles.
- Zumbrunn, Albrecht
-
p. 1357 - 1361
(2007/10/03)
-