Highly efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heteropoly acids in water

Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4（1H）-quinazolinones compounds in good to excellent yields.This method provides mild reaction conditions and clean reaction profiles,using a small quantity of catalyst and a simple workup procedure.

Silica-bonded S-sulfonic Acid as a Recyclable Catalyst for Synthesis of 2,3-Dihydroquinazolin-4（1H）-ones

2,3-Dihydroquinazolin-4（1H）-one derivatives were synthesized via a one-pot, three component reaction of isatoic anhydride and an aromatic aldehyde with ammonium acetate or primary amine catalyzed by silica-bonded S-sulfonic acid in ethanol at 80 ℃. The reaction work-up is simple and the catalyst is easily separated from the products by filtration. The heterogeneous catalyst was recycled for ten runs upon the condensation reaction of isa- toic anhydride and 4-chlorobenzaldehyde with ammonium acetate without losing its catalytic activity.

Synthesis and Crystal Structure of 3,3'-(2,2'-(Ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl))bis(2-(4-chlorophenylamino)quinazolin-4(3H)-one)

The title compound 3,3＇-（2,2＇-（ethane-1,2-diylbis（oxy））bis（ethane-2,1-diyl））bis（2- （4-chlorophenylamino）quinazolin-4（3H）-one） 3 （C34H30CI2N604, Mr = 657.54） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in space group P1 with a = 9.9185（8）, b = 10.6124（9）, c = 15.4064（13） A, α = 92.896（2）,β = 103.813（2）, γ= 94.635（2）°, V= 1565.5（2） A3, Z = 2, Dc = 1.395 g/cm^3,μ = 0.257 mm^-1, F（000） = 684, the final R = 0.0580 and wR = 0.1284 for 3400 observed reflections （I〉 2σ（I）. It remains triclinic in the crystal. Intra- and intermolecular N（3）-H（3A）…O（2）, N（6）-H（6A）…O（3） and C（19）-H（19A）…O（4） #1 （#1： 1-x, 1-y, -z） hydrogen bonds are observed in the title compound. A two-dimensional chain network is formed from the dimmers and intermolecular π-π interactions in the crystal structure. This open network has solvent-accessible voids （10A3）.

Synthesis and Crystal Structure of a New Quinazolinone Compound 2,3-Dihydro-2-(2-hydroxyphenyl)-3-phenyl-quinazolin-4(1H)-one

A new quinazolinone compound 2,3-dihydro-2-(2-hydroxyphenyl)-3-phenyl- quinazolin-4(1H)-one 3 ([C20H16O2N2]?C2H5OH, Mr = 362.42) and compound 2-(2-hydroxy- benzylidene-amino)-N-phenyl-benzamide 2 (C20H16O2N2, Mr = 316.34) were prepared from a precursor of 2-amino-N-phenyl-benzamide 1 (C13H12ON2, Mr = 212.25). Compound 3 was characterized by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic, space group Pbca with a = 1.2889(11), b = 1.6170(14), c = 1.7729(15) nm, V = 3.695(6) nm3, Z = 8, F(000) = 1536, Mr = 362.42, Dc = 1.303 g/cm3, μ(MoKα) = 0.087 mm-1, R = 0.0447 and wR = 0.0879. The crystal structure analysis indicates that the title compound has a two-dimensional network structure formed by hydrogen bonds and electrostatic interactions.

Synthesis and Crystal Structure of 1-(4-Fluorophenyl)-2-hexylthiobenzo[4,5]-furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H)-one

The crystal structure of the title compound 1-（4-fluorophenyl） -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5（1H） -one（C23H21FN4O2S,Mr = 436.5） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 13.9854（3） ,b = 17.2678（4） ,c = 18.1828（5）A,β = 99.364（2） °,V = 4332.58（18） A^3,Z = 4,Dc = 1.338,F（000） =1824,μ = 0.185 mm^-1,MoKa radiation（λ = 0.71073） ,R = 0.0538 and wR = 0.1162 for 4728 observed reflections with I 〉 2σ（I） . X-ray diffraction analysis reveals the fused rings of benzo[4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a] pyrimidin-5（1H） -one system are nearly coplanar. The crystal packing is mainly stabilized by weak intermolecular C-H···O hydrogen bond and π-π interactions.

Synthesis of some new bis-3,4-dihydropyrimidin-2(1H)-ones by using silica-supported tin chloride and titanium tetrachloride

Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as the catalysts for the synthesis of bisdihydropyrimidin -2(1H)-ones from aromatic dialdehydes,1,3-dicarbonyl compounds and urea at 90℃under solvent-free conditions.

H_3PMo_(12)O_(40) catalyzed three-component one-pot synthesis of 4,6-diarylpyrimidin-2(1H)-ones under solvent-free conditions

4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component one-pot condensation of acetophe-none derivatives,aldehydes and urea in the presence of trimethylsilyl chloride and a catalytic amount of HPMoOunder solvent-free conditions.

3-Phenyl/Pyridinyl Derivatives of <i>Trans</i>-2-(aryl/heteryl)vinyl-3<i>H</i>-quinazolin-4-ones: Synthesis and Fluorescent Properties

Novel 3-phenyl/pyridinyl-trans-2-(aryl/heteryl)vinyl-3H-quinazolin-4-ones 3a,b, 4a, 5a, 7a and their 6,7-difluoro de- rivatives 3c,d, 4b, 5b, 7b have been obtained by condensation of the correspondent 2-methylquinazolin-4-ones 1, 6 with aromatic (heterocyclic) aldehydes in the presence of ZnCl2 (AcONa) or by the reaction of 2-methyl-3,1-benzoxazin-4- ones 2 with the Shiff bases. Effects of aryl(heteryl) substituents on photophysical properties of (aryl/heteryl) quinazolinylethenes have been studied.

Synthesis and Characterization of a Novel Copoly(aryl ether ketone) Containing 4, 4'-Biphenyl-bis[4-phthalazin-1(2H)-one] Moiety

A new monomer of 4, 4-biphenyl-bis[4-phthalazin-1(2H)-one] was synthesized from biphenyl and phthalic anhydride, and a novel copoly(aryl ether ketone) (PPEK) was synthesized from 2, 2-bis(4-hydroxyphenyl)-propane (BPA), 4, 4'-biphenyl-bis-[4-phthalazin-1(2H)-one], 4, 4- difluorodiphenylketone (DFK). The monomer and copolymer were characterized by FT-IR and 1H-NMR. DSC and TGA were used to the novel polymer.

Synthesis and Crystal Structure of 4-Bromo-5-ethoxy-3-methyl-5- (naphthalen-1-yl)-1-tosyl-1H-pyrrol-2(5H)-one

The title compound 4-bromo-5-ethoxy-3-methyl-5-（naphthalen-l-yl）-l-tosyl-lH- pyrrol-2（5H）-one 1 （C24H22BrNO4S, Mr = 500.40） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 8.8562（15）, b = 18.118（3）, c = 14.055（2）A, β = 99.855（3）^o, V= 2221.9（6）A3, Z = 4, Dc = 1.496 g/cm^3,μ= 1.975 mm^-1, 2 = 0.71073A, F（000） = 1024, R = 0.0607 and wR = 0.1371.

Synthesis,Crystal Structure and Anti-tumor Activity of Ethyl 3-(4-methoxyphenyl)-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate

The title compound（ethyl 3-（4-methoxyphenyl）-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate） has been synthesized,and its crystal structure was characterized by X-ray single-crystal diffraction.The crystal belongs to monoclinic,space group P21/n,with a = 10.124（4）,b = 11.754（4）,c = 13.792（5） ,β = 111.533（3）o,V = 1526.6（10） 3,Z = 4,C17H19O6,Mr = 319.32,Dc = 1.389 g/cm3,F（000） = 676,λ（MoKα） = 0.71073 ,μ = 0.105 mm-1,R = 0.0660 and wR = 0.2027 for 2993 observed reflections（I 2σ（I））.The compound shows potent anti-tumor activity in vitro.

Sulfamic acid as a reusable and green catalyst for efficient and simple synthesis of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones in water or methanol

A series of 2,3-dihydroquinazolin-4（1H）-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditions.The reaction was efficiently promoted by 10 mol%sulfamic acid（SA,H_2NSO_3H） and the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity.

Catalytic activity of TiO_2 nanoparticles in the synthesis of some2,3-disubstituted dihydroquinazolin-4(1H)-ones

Green chemistry is playing an important role for synthesizing organic compounds, due to its eco-friendly nature and low cost. In green chemistry, metal nanoparticles exhibited some useful physical and chemical properties （catalytic activity）. Due to its diverse properties, nanoparticles can be utilized as a catalyst in various organic reactions. Recent research has been directed towards the utilization of eco- friendly and bio-friendly plant materials in nanoparticles synthesis. In our present work, TiO2 nanoparticles （TiO2 NPs） were synthesized using Annona squamosa peel extract and their catalytic applications were studied on the 2,3-disubstituted dihydroquinazolin-4（l1H）-one synthesis. Synthesized compounds were confirmed using FT-IR.1H NMR, 13C NMR and GC-MS analyses.

Synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by zirconium(Ⅳ) chloride as a mild and efficient catalyst

2,3-Dihydroquinazolin-4（1H）-ones have been synthesized in the high to excellent yields via condensation of 2-aminobenzamide with aldehydes and ketones in the presence of catalytic amount of ZrCl_4 in EtOH at room temperature.Mild reaction conditions, clean reaction media,simple workup and easy purification are advantages of this methodology.

Silica-bonded N-propylsulfamic acid as a recyclable catalyst for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones

2,3-Dihydroquinazolin-4（1H）-one derivatives are synthesized via a one-pot, three component reaction of isatoic anhydride and an aromatic aldehyde with ammonium acetate or primary amine catalyzed by silica-bonded N-propylsulfamic acid （SBNPSA） in refluxing ethanol.

Strontium chloride-catalyzed one-pot synthesis of 2,3-dihydroquinazolin-4(1H)-ones in protic media

A wide range of mono-and disubstituted 2,3-dihydroquinazolin-4（1H）-ones were obtained in high yields by condensation of isatoic anhydride,aldehydes with ammonium salts or primary amines in the presence of strontium chloride in aqueous ethanol under reflux.

Synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by a-chymotrypsin

We discovered that a-chymotrypsin has a promiscuous ability to catalyze the cyclocondensation of aromatic and aliphatic aldehydes with 2-aminobenzamides to afford the corresponding 2,3-dihydroquinazolin-4（1H）-ones successfully in high yields（90%–98%） under alcohol solvent. The catalytic activity of a-chymotrypsin was evaluated through investigating the temperature, the enzyme loading and the ratio of substrates in the enzyme-catalyzed reactions. The present method proves to be efficient and environmentally friendly in terms of short reaction time, high yield, green catalyst and the clean products obtained without further purification processes.

Eco-friendly and Efficient Synthesis of 2,3-Dihydroquinazolin-4（1 H）-ones

A simple and facile method for the synthesis of 2,3-dihydroquinazolin-4（1H）-ones through the direct cyclocon- densation of one-pot three-component cyclocondensation of isatoic anhydride, ammonium acetate （or primary amines） and aldehydes; and anthranilamide and aldehydes using silica supported ferric chloride （SiO2-FeCl3） as catalyst under solvent-free conditions is described.

Design, synthesis, and biological evaluation of quinazolin-4(3H)-one derivatives co-targeting poly (ADP-ribose) polymerase-1 and bromodomain containing protein 4 for breast cancer therapy

This study was aimed to design the first dual-target small-molecule inhibitor co-targeting poly(ADP-ribose)polymerase-1(PARP1)and bromodomain containing protein 4(BRD4),which had important cross relation in the global network of breast cancer,reflecting the synthetic lethal effect.A series of new BRD4 and PARP1 dual-target inhibitors were discovered and synthesized by fragmentbased combinatorial screening and activity assays that together led to the chemical optimization.Among these compounds,19 d was selected and exhibited micromole enzymatic potencies against BRD4 and PARP1,respectively.Compound 19 d was further shown to efficiently modulate the expression of BRD4 and PARP1.Subsequently,compound 19 d was found to induce breast cancer cell apoptosis and stimulate cell cycle arrest at G1 phase.Following pharmacokinetic studies,compound 19 d showed its antitumor activity in breast cancer susceptibility gene 1/2(BRCA1/2)wild-type MDA-MB-468 and MCF-7 xenograft models without apparent toxicity and loss of body weight.These results together demonstrated that a highly potent dual-targeted inhibitor was successfully synthesized and indicated that co-targeting of BRD4 and PARP1 based on the concept of synthetic lethality would be a promising therapeutic strategy for breast cancer.

L-Proline catalyzed one-pot multi-component synthesis of 2-(1,3-diphenyl-1H-pyrazol-4-yl)quinazolin-4(3H)-one derivatives and their biological studies

A new series of quinazolin-4（3H）-one derivatives containing a（1 3-diphenyl-1H-pyrazol-4-yl） core with substituents at the 2-position and aromatic or heteroaromatic substituents at the 3-position were synthesized using an L-proline catalyzed one-pot multi-component reaction approach.All the synthesized compounds were characterized and screened for their antimicrobial,antifungal and anti-tubercular activities.