Cyclic Urea Derivatives Research Articles

Inhibitory effect of a cyclic urea derivative on rubella virus replication.

1-(4-Morpholinomethyl)-tetrahydro-2(1H)-pyrimidinone (mopyridone) exhibited a marked activity against rubella virus (Judith and RA27/3 strains), a MIC50 value of 0.9 microM and selectivity ratio of 557.7 been found in the case of Judith strain. These data, in addition to the previous ones about its anti-alphavirus effects suggest the compound to be considered as a broad spectrum inhibitor of togavirus replication.

Quantitative structure–activity relationship studies on cyclic cyanoguanidines acting as HIV-1 protease inhibitors

A quantitative structure–activity relationship study has been performed on some cyclic cyanoguanidines that inhibit the enzyme HIV-1 protease (HIV-1-PR) and exhibit antiviral potency, and the results have been compared with those of cyclic urea derivatives. Both the enzyme inhibition activity and antiviral potency in cyclic cyanoguanidines as well as in cyclic urea derivatives are found to be primarily governed by hydrophobic property of substituents attached to nitrogen (P2/P2′) and further enhanced by OH or NH2 group, if any, present in the substituents. However, aromatic substituents are found to be unfavourable to both the activities of cyclic cyanoguanidines but not to any activity of cyclic urea derivatives. Cyclic urea derivatives are indicated to be more potent than cyclic cyanoguanidines. A model for the interaction of cyclic cyanoguanidines with the receptor is proposed.

Three-dimensional quantitative structure-activity relationship study on cyclic urea derivatives as HIV-1 protease inhibitors: application of comparative molecular field analysis.

Three-dimensional quantitative structure-activity relationship (3D-QSAR) models have been developed using comparative molecular field analysis (CoMFA) on a large data set (118 compounds) of diverse cyclic urea derivatives as protease inhibitors against the human immunodeficiency virus type 1 (HIV-1). X-ray crystal structures of HIV-1 protease bound with this class of inhibitors were used to derive the most probable bioactive conformations of the inhibitors. The enzyme active site was used as a constraint to limit the number of possible conformations that are sterically accessible. The test sets have been created keeping in mind structural diversity as well as the uniform simple statistical criteria (mean, standard deviation, high and low values) of the protease inhibitory activities of the molecules compared to the training sets. Multiple predictive models have been developed with the training sets (93 compounds in each set) and validated with the corresponding test sets (25 compounds in each set). All the models yielded high predictive correlation coefficients (q2 from 0.699 to 0.727), substantially high fitted correlation coefficients (r2 from 0.965 to 0.973), and reasonably low standard errors of estimates (S from 0. 239 to 0.265). The steric and electrostatic effects have approximately equal contributions, 45% and 55% (approximately), respectively, toward explaining protease inhibitory activities. This analysis yielded models with significant information on steric and electrostatic interactions clearly discerned by the respective coefficient contour plots when overlapped on the X-ray structure of the HIV-1 protease. The HINT CoMFA study revealed significant contribution of hydrophobicity toward protease inhibitory activity. The 3D visualization technique utilizing these contour plots as well as the receptor site geometry may significantly improve our understanding of the inhibitor-protease (HIV-1) interactions and help in designing compounds with improved activity.

ChemInform Abstract: Comparative Molecular Field Analysis (CoMFA) of a Series of Symmetrical Bis‐Benzamide Cyclic Urea Derivatives as HIV‐1 Protease Inhibitors.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Inhibition of pestivirus (BVDV) replication by a cyclic urea derivative

Inhibition of pestivirus (BVDV) replication by a cyclic urea derivative

Cyclic HIV-1 protease inhibitors derived from mannitol: synthesis, inhibitory potencies, and computational predictions of binding affinities.

Ten C2-symmetric cyclic urea and sulfamide derivatives have been synthesized from L-mannonic gamma-lactone and D-mannitol. The results of experimental measurement of their inhibitory potencies against HIV-1 protease were compared to calculated free energies of binding derived from molecular dynamics (MD) simulations. The compounds were selected, firstly, to enable elucidation of the role of stereochemistry for binding affinity (1a-d) and, secondly, to allow evaluation of the effects of variation in the link to the P1 and P1' phenyl groups on affinity (1a and 2-5). Thirdly, compounds with hydrogen bond-accepting or-donating groups attached to the phenyl groups in the P2 and P2' side chains (6 and 7) were selected. Binding free energies were estimated by a linear response method, whose predictive power for estimating binding affinities from MD simulations was demonstrated.

Regiospecific Functionalization of 1,3-Dihydro-2H-benzimidazol-2-one and Structurally Related Cyclic Urea Derivatives

Regiospecific Functionalization of 1,3-Dihydro-2H-benzimidazol-2-one and Structurally Related Cyclic Urea Derivatives

ChemInform Abstract: A New Route to Cyclic Urea Derivatives of Sugars via Phosphine Imides.

AbstractThe glycosyl azides (I) react with triphenylphosphine (II) to form the phosphine imides (III) which are converted to the phosphonium perchlorates (IV).

A new route to cyclic urea derivatives of sugars via phosphinimines

Sugar phosphinimines and the corresponding aminophosphonium salts were prepared from 2-amino-2-deoxy-d-glucosyl azide derivatives and their structures were established by 13C- and 13P-n.m.r. spectroscopy. A simple one-pot procedure, involving reaction of the azides with triphenylphosphine and carbon dioxide, provides an efficient access to cyclic urea derivatives.

ChemInform Abstract: CYCLIC UREA AND THIOUREA DERIVATIVES AS INDUCERS OF MURINE ERYTHROLEUKEMIA DIFFERENTIATION

AbstractDie Diamine (I) reagieren mit Schwefelkohlenstoff zu den Dithiocarbamaten (II), die thermisch zu den Thioharnstoffen (III) cyclisieren.

Cyclic urea and thiourea derivatives as inducers of murine erythroleukemia differentiation.

A series of derivatives of tetramethylurea, a known inducer of the differentiation of Friend erythroleukemia cells, has been synthesized and tested for its capacity to induce erythroid maturation, as measured by the synthesis of hemoglobin. Cyclic urea and thiourea derivatives consisting of five-, six-, and seven-membered ring systems containing N-alkyl substituents were prepared. Most of these agents were relatively effective inducers od differentiation, with N-alkyl substitution appearing to be essential for maximum response. The most potent agents developed were N,N'-dimethyl cyclic ureas. Exposure to concentrations of 2 to 4 mM of these derivatives resulted in more than 90% of the cell population achieving a differentiated state. Under these conditions, the parent compound, tetramethylurea, was slightly less efficacious, causing differentiation of only 68% of the population at its maximum effective level of 4 mM.

ChemInform Abstract: TOPICAL MOSQUITO REPELLENTS. XII: N‐SUBSTITUTED UREAS AND CYCLIC UREAS

AbstractDie Repellent‐Wirkung der auf konventionellem Wege synthetisierten Harnstoffe (II) und (IV) gegenüber Aedes aegypti ist teilweise besser als die des Diethyltoluamids.

Topical Mosquito Repellents XII: N-Substituted Ureas and Cyclic Ureas

Various N-substituted urea and cyclic urea derivatives were synthesized and evaluated as repellents for Aedes aegypti mosquitoes with an in vitro blood-feeding test system. Several compounds were superior to diethyltoluamide.

Physical Chemistry of Crosslinking

Crosslinked cotton fabrics suffer significant losses in strength and abrasion resistance. In order to understand why these losses occur and also to reduce them, the physical chemistry of the process of crosslinking and the role of adsorption in the crosslinking reaction were studied. An attempt is made to relate adsorption and reactivity of different cyclic urea derivatives (DMEU, DMPU, DHEU, and DMDHEU) to the molecular structure, solution properties, pH, nature and concentration of catalyst, temperature, and time of reaction. Solution properties of crosslinking compounds were determined from measurements of electrical conductivity and the depression of the freezing points of aqueous solutions of the crosslinking compounds. A study on chemisorption with different cyclic urea derivatives showed that the maximum chemisorption takes place at pH 2.5 with DMEU and DMPU, and at 0.8 and zero pH with DHEU and DMDHEU, respectively. The kinetics of chemisorption in these crosslinking compounds revealed that the amount of DMEU and DMPU chemisorbed increases initially with time and then decreases and finally reaches an equilibrium value. The chemisorption of DHEU and DMDHEU increase with time and finally reach an equilibrium value. The data show that the chemisorption of these crosslinking compounds are pseudo first-order reactions with respect to the concentration of the crosslinking agent. Equilibrium physical and chemisorption for all the four crosslinking compounds were studied and found to be of the Langmuir type. The thermodynamic parameters such as affinity, enthalpy, and entropy of chemisorption were calculated. The saturation value for different crosslinking compounds are found to be in the order DMEU > DMPU > DHEU > DMDHEU.

Antifungal activities of mono- and di-SCCl 3 substituted compounds: Structure-activity correlations

The mono- and di-N-SCCl 3 substituted derivatives of lactams, cyclic urea, 5,5-diphenylhydantoin and 5-ethyl-5-phenylbarbituric acid were synthesized. Many of these compounds have not been reported previously. The antifungal activities were determined by spore germination method using Stemphylium sarcinaeforme, Monilinia fructicola, Helminthosporium maydis and Alternaria solani. Among the lactam and cyclic urea derivatives studied 1,3-bis(trichloromethylthio)-2-imidazolidinone appears to be the most active compound against S. sarcinaeforme, and has activity slightly below those of the commercial products captan and folpet. Among the diphenylhydantoin and phenobarbital derivatives the mono-SCCl 3 compounds appear to be more potent than the disubstituted compounds in most of the cases examined, but they are not as active as the imidazolidinone derivative. The antifungal activity appears to be highly dependent on the lipophilic character as measured by the 1-octanol/water partition coefficient. Since the bis-SCCl 3 compounds are less potent than the mono-substituted compounds in both of the series of compounds studied, it is evident that the whole molecule rather than any decomposition products of the N-SCCl 3 moiety is responsible for the fungitoxicity.

ON THE TWO-STEP WASH AND WEAR FINISHING OF COTTON FABRICS WITH DIEPOXY COMPOUNDS

Two-step wash and wear finishing of cotton fabrics with diepoxy compounds was investigated. Cotton fabrics were padded with diepoxy compounds and cured under dry conditions in the presence of acidic catalysts (first treatment) and recured under wet conditions in the presence of alkali catalysts by the timing or steaming method (second treatment). The diepoxy compounds studied were as follows.(1) Diepoxy compounds soluble in water: diglycidyl ether (Epoxide I), glycerin diglycidyl ether (Epoxide III), polyethylene diglycidyl ether (Epoxide VI).(2) Diepoxy compounds insoluble in water: ethylene glycol diglycidyl ether (Epoxide II), butanediol diglycidyl ether (Epoxide IV), vinylcyclohexane dioxide (Epoxide VII).Both wet and dry crease recovery angles increased after the second treatment; the steaming method was more effective than the timing method. The high wet crease recovery angles obtained by the second wet curing were durable to repeated laundering. The diepoxy compounds soluble in water were more effective in the crease resistant finishing. The smaller the molecular weight of the diepoxy compounds, the more the improvement of the crease recovery angles. The tearing strength decreased by the second curing, the decrease was smaller however, than that by the first curing.Combination of Epoxide III and conventional cyclic urea derivatives for the two-step treatment was investigated. It was found that dimethyloldihyroxyethyleneurea (DMDHEU) was the most effective coreactant.Ten unsymmetrical sodium-4, 4′-bis-(substituted, 1, 3, 5-triazyl-6)-diaminostilbenedisulfonate 2, 2′ synthesized in the laboratory were compared with a commercial symmetrical whitening agent. The whitening agent was best applied on cotton before the padding of diepoxy compounds.Shirts were made from the cotton fabrics prepared by the two-step Epoxide treatment andthe wearing test was performed for 60 days and 30 launderings.

Influence of structure of cyclic urea derivatives on their reactivities with cotton

AbstractThe structure of the cyclic urea influenced the rate of reaction with cotton cellulose and the mechanism by which reaction occurred. Reaction of N, N′‐dimethylolethylene‐urea (DMEU) and N, N′‐dimethylolpropyleneurea (DMPU) with cellulose in presence of inorganic salt catalysts proceeded through methylol hydroxyls and at the same rate; but reaction mechanism differed. With DMEU, N → metal ion coordination occurred and SN2 mechanism prevailed. With DMPU, O → metal ion coordination resulted.Reaction of dihydroxyethylene urea (DHEU), N, N′‐dimethyldihydroxyethyleneurea (DMeDHEU), and N, N′‐dimethyloldihydroxyethyleneurea (DMDHEU) with cotton cellulose proceeded through ring hydroxyls with the formation of a carbonium ion, indicating an SN1 mechanism. The much faster rate of reaction with DMeDHEU than with DHEU was attributed to the more electronegative environment of its ring hydroxyl, while the much slower rate of reaction of DMDHEU was attributed to hydrogen bonding between its methylol and ring hydroxyls.