1234-21-5Relevant articles and documents
Investigation of active sites using solid state 27Al and 31P MAS NMR in ceramic amorphous aluminophosphate materials prepared from different potassium salts of phosphate for the synthesis of diphenyl urea derivatives
Harish,Kathyayini,Baby, Bindhu,Nagaraju
, (2021/04/19)
Ceramic amorphous aluminophosphate (CAmAlP) catalysts were prepared by precipitation method using different phosphate salts of potassium such as KH2PO4, K4P2O7 and K2HPO4 as well as H3PO4. The prepared materials were characterized by PXRD, FT-IR, XPS, SEM, BET Surface area, NH3-TPD, 27Al NMR and 31P NMR analytical methods. The catalytic activity of the materials was checked in the synthesis of diphenyl urea (DPU) from aniline and diethyl carbonate, under refluxing conditions. Further, the general application of the catalysts was tested using various substituted anilines. The recyclability of the catalysts was also studied. Uncertainties in percentage yields were calculated to check the reproducible surface properties. The P-XRD, BET Surface area and NH3-TPD results indicated that the materials were amorphous with mesoporous texture, surface areas and acidities in the range 200–260 m2/g and 0.4–0.7 mmol/g respectively. 27Al NMR studies revealed that Al is present in three different coordination states such as tetrahedral, pentagonal and octahedral. The relative percentages of these Al sites depends on the type of the potassium precursor phosphate salt used. Both tetrahedral and pentagonal Al sites in conjunction with each other represented catalytically active sites. An increase in the pentagonal sites contributed to additional increments to the catalytic activity of CAmAlP. The catalyst prepared from KH2PO4 was found to be the best and demonstrated 96% DPU yield.
1,3-disubstituted ureas as antiglycating agents
Perveen, Shahnaz,Mustafa, Sana,Khan, Khalid Mohammed,Choudhary, Muhammad Iqbal
, p. 1603 - 1611 (2014/03/21)
Twenty one (21) 1,3-disubstituted urea derivatives were screened for their antiglycating potential and some of them displayed promising activity. Compound N-butyl-N'-(4-nitrophenyl)urea (6) and Nisopropyl-N'-(4-nitrophenyl)urea (18) exhibited excellent activity and could be investigated in search of medicines treating diabetes and associated complications.
Substituted urea derivatives: A potent class of antidepressant agents
Perveen, Shahnaz,Mustafa, Sana,Khan, Muhammad A.,Dar, Ahsana,Khan, Khalid M.,Voelter, Wolfgang
experimental part, p. 330 - 336 (2012/08/28)
A series of fourteen (14) N-nitrophenyl-N'-(alkyl/aryl)urea and symmetrical 1,3-disubstituted urea derivatives were synthesized and evaluated for their antidepressant activity in mice. Among them, N-(4-nitrophenyl)-N'-(1'- phenylethyl)urea (1), demonstrat
