Quinazoline derivatives has attracted considerable attention due to their significant biological activities[1, 2], especially antiallergic, antifungal, anti-HIV, antihypertensive, anti- inflammatory, antibacterial, anticonvulsant[9, 10], antithrombotic, antitubercular, CNS depressant, antihistaminic. In this paper, we report a new route for the synthesis of N3 substituted derivatives of quinazolinone.
A mixture of 2-substituted-4H-3, 1-benzoxazin-4-one1, 2 (0.01 mol) and selected amino acids namely, aspartic acid, arginine, histidine, tyrosine, threonine, valine and methionine (0.01 mol) were refluxed in a pyridine for 6 h. The mixture was then poured in an ice/water mixture, stirred and left to allow the white solid precipitate to settle down. The solid was filtered, washed, dried and finally crystallized from the proper solvent to yield compounds 3-14, respectively.
Quinazoline and quinazolinone derivatives are well-known bioactive heterocycles owing to their therapeutic diversity and extensive medicinal application in drug design and pharmaceutics. A series of 2-methyl-3-substituted quinazolin-4(3H)-one derivatives 8a-q was herein synthesized from synthetic conversion of anthranilic acid to 2-methyl-4H-3,1-benzoxazi-4-one, 7 which was subsequently transformed to the targeted 2,3-disubstituted quinazolin-4(3H)-one derivatives 8a-q by reacting with some notable amino-containing moieties via an ameliorable pathway. The catalyst- free synthesis was successful achieved by careful reaction optimization study using solvent choice and reaction temperature variability as key parameters. The chemical structures of the synthesized compounds were confirmed by IR, UV, 1 H-NMR, 13 C-NMR and DEPT-135 as well as analytical
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In the present work, six novel 2-[4-(substituted aryl)piperazine-1-yl]-3- (4-hydroxy phenyl)quinazolin-4(3H)-one were synthesized by condensation, it is condensation between 3-(4-hydroxy phenyl )2- chloro,4(3H)quinazolinone and substituted substituted piperazine to yield 2-[4-(substited aryl)piperazine-1-yl]-3-(4-hydroxy phenyl)quinazolin-4(3H)-one derivatives. The structures of the synthesized compounds were characterized on the basis of IR, NMR and Mass spectral data. Among all synthesized compounds only few selected compounds are screened for their antihypertensive activity by tail-cuff method, Prazocin is employed as a reference standard. From the results it is concluded that, compound III and IV exhibited potent, rest of compounds exhibited mild to moderate activity antihypertensive activity.
2,4(1H,3H)-Quinazolinedione derivatives are of interest because of their biological activity, and they have been widely used as key structures in medicinal drugs (Goto et al., 1993; Mohri, 2001; Mizuno et al., 2007). We herein report the crystal structure of the title compound (I). In the molecule (Fig. 1), the bond lengths and angles are within normal ranges. Intermolecular N—H···O hydrogen bonds involving amine NH and carbonyl groups O atoms form a two dimensional network (Table 1 and Fig. 2). Weak π–π stacking interactions are also observed in the crystal structure.
The antimicrobial activity of the synthesized phenyl quinazoline on two kinds of bacteria namely, staphylococcus aureous and Escherichia coli was investigated. The investigation was carried out via cup method with nutrient agar as a media for bacterial growth using 0.1ml of DMF as a solvent for all samples. The agar was scoop up from the sterilized cork borer cups and transferred into a bacterially inoculated petri dish. After then, a 0.1 ml aliquot of the solution of the investigated compound was introduced to each dish and the dishes were incubated for 24 hrs at 37°C.
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one ring system is a core structure in various pharmaceutical agents displaying a broad spectrum of biological activity profile [17-19]. Thiazolidinones explored diverse biological activities such as antimicrobial , anti-inflammatory , analgesic [22,23], antibacterial as well as antifungal [24-28], anticancer , anti-HIV . Thiazolidin-4-ones also found in nature; thus actithiazic acid [(-)2-(5-carboxypentyl)thiazolidin-4-one] isolated from the strains of Streptopmyces displayed highly specific invitro activity against Mycobacterium tuberculosis [31,32]. On the other hand, piperazines and substituted piperazines are important pharmacophores that can be found in many marketed drugs, such as the Merck HIV protease inhibitor Crixivan [33-35] and drugs under development [36-38]. Piperazinyl linked ciprofloxacin dimers reported as potent antibacterial agents against resistant strains  and also explored several other biologically activity viz. insecticidal , anti-inflammatory , antibacterial  and antigungal . It is found that bacterial infections generally result into pain and inflammation. In normal practice, two groups of drugs (chemotherapeutic, analgesic and anti-inflammatory) are prescribed simultaneously. Unfortunately, currently none of these drugs possess these three activities in a single compound. A large amount of research work and activities has been undertaken to synthesize new derivatives of quinazoline-4(3H)-ones having different biological activities. In continual of our research work [20,44], it is interesting to synthesize and characterize novel quinazoline-4(3H)-one derivatives.
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Antibacterial and antifungal diseases are very common all over the world. Currently used antimicrobial agents are not effective due to the resistance developed by the microbes, and therefore, it is an ongoing effort to synthesize new antimicrobial agents. Quinazolin-4(3H)-ones with substitution at position 3, has been reported to be associated with anti-microbial properties. 29-36 Examples of these substitutions were substituted phenyl ring moieties 29, 30 bridged phenyl rings 31, 32 heterocyclic rings 33 and aliphatic systems 34, 35 . The Baylis–Hillman reaction 37-41 has attracted the attention of organic chemists as this reaction provides synthetically useful multifunctional molecules. Inspired with the biological profile of quinazolinones and their increasing importance in pharmaceutical and biological fields, and in connection with our research on the design and synthesis of biologically active and pharmacologically important new heterocycles and their derivatives 42-48 it was thought worthwhile to synthesize the title compounds with a view to obtain certain new chemical entities and to have them evaluated for their antimicrobial activity. On the other hand, to the best of my knowledge previously, there is no report, on the synthesis of Baylis-Hillman derived 3-substituted cinnamyl quinazolinone derivatives. In this article, we illustrate the simple and efficient synthesis of Baylis-Hillman derived 3-N-cinnamyl substituted quinazoline-4-one derivatives and 4-O-cinnamyl substituted quinazoline derivatives and screened for their antimicrobial activity.
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chemical substances which may serve as leads for designing novel antitumor agents, we are particularly interested in the present work with quinazoline derivatives which have been identified as a new class of cancer chemotherapeutic agents with significant therapeutic efficacy against solid tumors. It is well known that quinazoline derivatives are potent inhibitors of Epidermal growth factor receptor (EGFR). Combining the inherent DHFR inhibition activity of the quinazolines and those functional groups in one structure was expected to produce more active compounds. Most of those functional groups are also known to increase lipid solubility. The present study is a continuation of our previous efforts aiming to create novel synthetic lead compound and its in vitro testing for future development as DHFR inhibitor.
A variety of aza-heterocycles have been proven to be very effective in various therapeutic diseases due to their wide and distinct biopharmaceutical activities. Quinazolin-4(3H)-ones [1-5] are classes of fused heterocycles that are of significant interest because of their biological activities such as anti-cancer [6,7], antitumor [8-12], antioxidant , antimicrobial [14,15], antifungal , anticonvulsant [17,18], anti-HIV , anti-HCV  anti-TMV  activities. Recently, a methodological study of the literature suggested that this type of fused heterocycles has a broad spectrum of applications as antioxidants [22-28]. Furthermore, there are many different reports that evaluate the antioxidant activity of vanillin against different free radicals [29-33]. On the other hand, * Corresponding author:
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4(3H)-Quinazolinones and their derivatives constitute an important class of heterocyclic compounds. They occupy an important position in medicinal chemistry, presenting a wide range of bioactivities. Many of them display anti-microbial, anti-tubercular, anticancer, anti-HIV, anti-fungal, anti-inflammatory, anticonvulsant, antidepressant, hypolipidemic, antiulcer and analgesic or immunotropic activities and are also known to act as thymidylate synthase, poly (ADP-ribose) polymerase (PARP) protein tyrosine Kinase inhibitors and dihydrofolate reductase inhibitors. As pesticides, they are used as insecticides, fungicides and antiviral agents such as TMV, CMV inhibitors. It is found in many bioactive natural products and looking at the biological significance of Quinazolinone nucleus it was thought to design and synthesize new derivatives of it.
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Heterocyclic chemistry comprise as a minimum half of all organic chemistry research worldwide. In particular, heterocyclic structures form the basis of a lot of pharmaceutical, agrochemical and veterinary products. Quinazoline nucleus is a very attractive and useful scaffold in medicinal chemistry. The synthesized compounds were screened for in vitro and in-vivo antioxidant activity. The presence of antioxidants has been reported to protect lipids, blood and body fluids against the attack of reactive oxygen species like peroxide, superoxide and hydroxyl radicals. The presence of antioxidants in Test compounds (7a1, 7a2, 7a3, 7a4, 7a5, 7a6, 7a7, 7a8, 7b1, 7b2, 7b3, 7b4, 7b5, 7b6, 7b7 & 7b8) might be responsible for their observed antioxidant activity.
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One day prior of these testing, inoculations of the above fungal culture were made in the Sabouraud - Dextrose Agar and incubated the cultures of Candida albicans and Aspergillus niger at 25 °C for 48 h and 7 days respectively. Using sterile saline solution harvested the Candida albicans cultures and diluted with the sterile saline solution to bring the count to about 1 x 10 8 per ml. Similarly harvested
the ligand and their complexes were recorded on Perkin Elmer-577 using KBr disc. The electronic spectra were recorded on a Car y 2390 spectrophotometer. Magnetic susceptibility was recorded by Gouy method using Hg[Co(NCS) 4 ] as a calibrant. The molar conductivity was measured by systronics conductivity meter model 303 using DMF as a solvent. Analytical data, colour, electronic spectra, molar conductance measurement, decomposition temperature and molar mass of the ligand and metal complexes are recorded in Table- 1 and the important IR bands are recorded in Table-2.
The ﬂasks were shaken gently to avoid formation of air bubbles. This medium was transferred to Petri dishes of 9-cm diameter in 25 mL portions, so as to obtain 4-5 mm thickness of the media layer. The plates were left at room temperature to allow solidiﬁcation of the media. In each Petri plate, four cups of suitable diameter were made with a sterile borer. All these procedures were conducted aseptically under laminar air ﬂow workstation. The test com-pounds and Ciproﬂoxacin (Symed Lab India Pvt Ltd.,
 Wan, Z. Y.; Tao, Y.; Wang, Y. F.; Mao, T. Q.; Yin, H.; Chen, F. E.; Piao, H. R.; Clercq, E. D.; Daelemans, D.; Pannecouque, C. Hybrid chemistry. Part 4: Discovery of etravirine–VRX- 480773 hybrids as potent HIV-1 non-nucleoside reverse transcriptase inhibitors. Bioorg. Med. Chem. 2015, 23, 15, 4248–4255.
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orthogonal to the isobenzofuran-1-one ring system. The molecules, translated by one unit cell along the a-axis direction, are linked into a chain by intermolecular C— H O hydrogen-bonding interactions, and the inversion- related molecules of adjacent chains are linked via C—H O hydrogen bonds to form a ribbon structure.
Gazi Irez et al.,  In this study, (hydroxyimino)(2-phenyl(1,2,3,4-tetrahydroquinazolin-2- yl)) methane and (hydroxyimino) (2-(2-thienyl)(1,2,3,4- tetrahydroquinazolin-2-yl)) methane were synthesized by the condensation of 2-(hydroxyimino)-1-phenylethan-1- one and 2-(hydroxyimino)-1-(2-thienyl) ethan-1-one with 2-aminobenzylamine (2-ABA). Complexes of these ligands with Co 3+ were prepared with a metal: ligand ratio of 1:2. The ligands and their complexes were elucidated on the basis of elemental analyses, AAS, FT-IR, 1 H- and 13 C-NMR spectra, mass spectra, magnetic susceptibility measurements, and molar conductivity. (2008)
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10. Srivastava Sanjay K, Jha Amrita, Agarwal Shiv K, Mukherjee Rama, and Burman Anand C. Synthesis and structure-activity relationships of potent antitumor active quinoline and naphthyridine derivatives. Anti-Cancer Agents Medi Chem 2007; 7(6): 685-709.
The structure of the entire synthesized compound was confirmed by spectral analysis (IR, 1 HNMR, 13 C-NMR, Mass). The IR spectrum of compound (6a) shows that absence of C ≡ N peak in 2250 cm -1 and presence 3328 cm -1 for NH group and 1691 cm -1 for C=O of the carbonyl group indicates the formation of 6a. In 1 H NMR the characteristic peak observed as a singlet for NH proton at δ 8.01 ppm and as a singlet for methine proton at δ 4.01 ppm and all other protons were observed in the respective aromatic region ( δ 7.65-7.56) ppm. The mass spectrum of the compound showed a M+ ion peak at m/z 386.09 for the molecular formula C 22 H 15 ClN 4 O. The synthetic procedure