18006-57-0Relevant academic research and scientific papers
Sulfated polyborate-catalyzed efficient and expeditious synthesis of (un)symmetrical ureas and benzimidazolones
Rekunge, Deelip S.,Khatri, Chetan K.,Chaturbhuj, Ganesh U.
, p. 4304 - 4307 (2017)
The excellent catalytic potential of sulfated polyborate is utilized in the synthesis of (un)symmetrical ureas and benzimidazolones by heating amines or substituted OPDA and urea or N-phenylureas under a solvent-free condition at 120 °C is described. The key advantages of the present protocol are phosgene-free, and other hazardous reagents or organic solvent free, high reaction rates and yields, simple workup procedure, and recyclability of the catalyst.
One-pot sequential synthesis of isocyanates and urea derivatives via a microwave-assisted Staudinger-aza-Wittig reaction
Carnaroglio, Diego,Martina, Katia,Palmisano, Giovanni,Penoni, Andrea,Domini, Claudia,Cravotto, Giancarlo
supporting information, p. 2378 - 2386 (2014/01/06)
A fast and efficient protocol for the synthesis of N,N'-disubstituted urea derivatives from alkyl halides and primary or secondary amines has been developed. The synthetic pathway combines nucleophilic substitutions and a Staudinger-aza-Wittig reaction in the presence of polymer-bound diphenylphosphine under 14 bar of CO2 pressure and has been performed in a one-pot two-step process. The protocol has been optimized under microwave irradiation and the scale-up experiment has been conducted under conventional conditions in a Parr reactor. The final compounds were isolated after simple filtration in almost quantitative overall yields which makes this procedure facile and rapid to execute.
Ureylene anticonvulsants and related compounds
Dimmock,Vashishtha,Stables
, p. 490 - 494 (2007/10/03)
The results from a previous study led to the postulate that a number of aryl semicarbazones displaying anticonvulsant activity in the maximal electroshock (MES) screen interacted at both a hydrophobic and a hydrogen bonding areas on a specific binding site. These two parts of the binding site may be referred to as areas A and B, respectively. In order to circumvent the possible problems of the carbimino group in semicarbazones, such as toxicity and acid lability, some related ureylenes were considered. Initial evidence suggested that a second lipophilic group in the molecule was advantageous; this group may interact at area C on the proposed binding site. Most of the compounds prepared with a view to interacting at areas A, B and C showed protection in mice against MES induced siezures. Of particular interest were the compounds 1d, j which contained an α-methylbenzyl group attached to the N1 atom of the ureylenes which afforded good protection in the MES screen. The areas A and C at which lipophilic moieties were considered to interact were capable of accommodating groups of different sizes as measured by their solvent accessible surface areas. A number of compounds were active when given orally to rats and devoid of neurotoxicity at the doses utilized. Several compounds including 1d, f, j, 2d are useful prototypic molecules for subsequent development of further novel anticonvulsants.
