13201-86-0Relevant 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.
Ortho-substituent effects on diphenylurea packing motifs
Solomos, Marina A.,Watts, Taylor A.,Swift, Jennifer A.
, p. 5065 - 5072 (2018/03/01)
Hydrogen bonding between urea groups is a widely used motif in crystal engineering and supramolecular chemistry studies. In an effort to discern how the steric and electronic properties of substituents affect the molecular conformation and crystal packing
Antiproliferative effects of novel urea derivatives against human prostate and lung cancer cells; And their inhibition of β-glucuronidase activity
Perveen, Shahnaz,Mustafa, Sana,Qamar, Kehkashan,Dar, Ahsana,Khan, Khalid M.,Choudhary, Muhammad Iqbal,Khan, Ajmal,Voelter, Wolfgang
, p. 1099 - 1113 (2014/03/21)
Twenty-one novel urea derivatives were synthesized and their structures characterized by mass, NMR, IR, and UV spectroscopy. These compounds were evaluated for their antiproliferative profile against human PC-3 (prostate) and NCI-H460 (lung) cancer cell lines. Among them, compound 21 N-(3-nitrophenyl)- N′-(1-phenylethyl)urea was found to be active against both PC-3 (IC 50 ± SEM: 20.13 ± 0.91 μM) and NCI-H460 (GI 50: 22 ± 2.6 μM) cell lines; hence has the potential to be further studied as anticancer agent. These compounds were also investigated for their ability to inhibit urease, β-glucuronidase, and phosphodiesterase enzymes. N-(2,6-Dimethylphenyl)-N′-(4′-nitrophenyl)urea (1) demonstrated 90 % inhibition of β-glucuronidase enzyme (IC50 ± SEM: 3.38 ± 0.043 μM).
A simple and efficient synthesis of diaryl ureas with reduction of the intermediate isocyanate by triethylamine
Zhou, Shuguang,Yao, Ting,Yi, Jicheng,Li, Dashuai,Xiong, Jing
, p. 315 - 319 (2013/07/27)
Thirty symmetrical diaryl urea derivatives were synthesised in moderate to excellent yields from arylamine and triphosgene with triethylamine as a reducing agent for the intermediate, isocyanate. It was significant that part of the products could be collected in almost quantitative yield without column chromatography. The procedure under mild reaction conditions was tolerant of a wide range of functional groups. The structures of the compounds were determined by NMR, MS and X-ray crystallographic analyses.
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
An unplanned synthesis of symmetrical 1,3-disubstituted ureas
Perveen, Shahnaz,Mustafa, Sana,Khan, Khalid Mohammed
experimental part, p. 229 - 234 (2011/10/05)
When urea derivatives (N-aryl-N′, N'-dialkyl urea) or (N-aryl-N'-alkyl/arvl urea) la-lu react with diethylcarbamyl chloride at 50-60°C symmetrical 1,3-disubstituted ureas 2a-2f were furmed as major products instead of forming ployureas.
Co(acac)3/BMMImCl as a base-free catalyst system for clean syntheses of N,N′-disubstituted ureas from amines and CO2
Li, Jian,Guo, Xiaoguang,Wang, Liguo,Ma, Xiangyuan,Zhang, Qinghua,Shi, Feng,Deng, Youquan
experimental part, p. 1534 - 1540 (2010/11/04)
A base-free catalyst system Co(acac)3/BMMImCl was developed for the carbonylation of amines with CO2. 45%2-81% isolated yields for N,N-dialkylureas and 6%2-23% isolated yields for N,N-diarylureas were obtained. The catalyst system was recovered and reused without significant loss in activity. In this catalyst system, the base catalyst and chemical dehydrant were efficiently avoided. Different reaction conditions were also discussed and a postulated mechanism was proposed.
Effect of successive increase in alcohol chains on reaction with isocyanates and isothiocyanates
Perveen, Shahnaz,Yasmin, Arfa,Khan, Khalid Mohammed
experimental part, p. 18 - 23 (2010/04/23)
The reaction of isocyanates and isothiocyanates with long-chain alcohols, e.g. n-hexanol, n-heptanol and n-octanol, exclusively gave N-aryl-O-alkyl carbamates, while N-aryl-O-alkyl carbamates were formed along with symmetrical 1,3-disubstituted ureas and thioureas when the same reactions were carried out with small-chain alcohols at room temperature without using any solvent.
Expeditious method for synthesis of symmetrical 1,3-disubstituted ureas and thioureas
Perveen, Shahnaz,Abdul Hai, Syed M.,Khan, Rashid A.,Khan, Khalid Mohammed,Afza, Nighat,Sarfaraz, Tahira B.
, p. 1663 - 1674 (2007/10/03)
Symmetrical 1,3-disubstituted ureas and symmetrical thioureas have been synthesized from corresponding isocyanates, diisocyanates, and isothiocyanates by a new versatile, simple, and quick method in the presence of tertiary amines at room temperature. The method under discussion has several advantages over the existing techniques, as it is simple to carry out, does not require complicated equipment, has a simple workup, and does not use expensive chemicals. Moreover, the yields are almost quantitative. This method has potential in commercial applications. Copyright Taylor & Francis, Inc.
