Synthesis Of Quinazolin-4 Research Articles

Synthesis of quinazolin-4(3H)-ones in natural deep eutectic solvents: Comparison of various synthetic methods and calculation of ADME properties

In this work, natural deep eutectic solvents (NADESs) were used as a worthy alternative to organic solvents in combination with microwave-assisted, ultrasound-assisted, and mechanochemical synthesis for the preparation of substituted quinazolin-4(3H)-one derivatives 1–29. Choline chloride-based (ChCl) NADESs were tested in the condensation of 2-methylbenzoxazin-4-ones (f–j) and amines or hydrazides to obtain substituted quinazolin-4(3H)-one derivatives. The reaction conditions were optimized for each method using 2-methylbenzoxazin-4-one and 4-chloroaniline as model substrates. Their structures were also confirmed by 1H- and 13C NMR and mass spectrometry. Prediction of biological activities and drug-like properties of the compounds was performed by in silico methods. Among 20 tested NADESs, choline chloride/urea was proven to be the best solvent and catalyst system for the synthesis of target compounds. Synthesized quinazolin-4(3H)-ones were obtained conventionally with 17–73% yields, by microwave-assisted synthesis (10–41%), ultrasound-assisted synthesis (15–56%), and mechanochemical synthesis (45–87%), respectively. Synthesized quinazolin-4(3H)-ones have the potential to be anticonvulsants, skeletal muscle relaxants, and antifungal drugs. These green procedures provide better methods for the synthesis of substituted quinazolin-4(3H)-ones, because mechanochemical synthesis, among others, shown the best efficiency. Leading compounds for the design of future drugs were pointed out.

Cobalt-Centered Supramolecular Nanoensemble for Regulated Aerobic Oxidation of Alcohols and "One-Pot" Synthesis of Quinazolin-4(3H)-ones.

The supramolecular assemblies of the donor-acceptor (D-A) system Im-Tpy, having phenanthro[9,10-d]imidazole as the donor and terpyridyl group as the acceptor unit, have been developed, which serve as supramolecular host to stabilize Co(II) in its nanoform. The as-prepared supramolecular nanoensemble Im-Tpy@Co in DMSO:water (7:3) shows high thermal stability and photostability. Even in the case of solvent mismatch, i.e., on dilution with cosolvent THF/DMSO, insignificant changes were observed in the size/morphology of the nanoensemble. The as-prepared Im-Tpy@Co nanoensemble in low catalytic loading (0.1 mol % of Co) catalyzes the oxidation of a wide variety of alcohols to aromatic aldehydes/ketones using visible light radiations as the source of energy without the need of any additive at room temperature. In comparison to already reported systems, the Im-Tpy@Co nanoensemble exhibits high turnover numbers (TONs) and turnover frequencies (TOFs). The practical application of the catalytic system has also been demonstrated in the gram-scale synthesis of 4-chlorobenzaldehyde. The Im-Tpy@Co nanoensemble exhibits recyclability up to four catalytic cycles with insignificant leaching and morphological changes. The present study also demonstrates the catalytic activity of the Im-Tpy@Co nanoensemble in "one-pot" synthesis of quinazolin-4(3H)-ones from 2-aminobenzamide and primary alcohols with better efficiency in comparison to other transition-metal-based catalytic systems.

Synthesis of Quinazolin-4(3H)-ones via a novel approach

The present work was designed based on the new multi-component reaction, which forms 2-aryl/alkyl-quinazolin-4(3H)-ones in a one-pot reaction with good to excellent yields (86–97 %) using 2-aminobenzoic acid, organic acid, and ammonium hexafluorophosphate (NH4PF6). The advantages of the presented method include inexpensive and readily available starting materials, simple procedures, and easy workup. In this newly discovered method, ammonium hexafluorophosphate (NH4PF6) was used as a highly efficient reagent and catalyst for quinazolin-4(3H)-ones synthesis. All of the synthesized compounds were characterized by 1H NMR and 13C NMR techniques.

Diaryliodonium salt as oxidant in sp3 C-H activation and synthesis of quinazolin-4(3H)-ones

Reactions of 2-aminobenzamides with diaryliodonium salts in N,N-dimethylacetamide (DMA) led to the formation of unexpected product quinazoline-4(3H)-one derivatives instead of the desired N-arylated 2-aminobenzamides. Most likely the diaryliodonium salts activated the sp3 C-H of N-methyl group of DMA through oxidation thereby produced an iminium species, the reaction of which with 2-aminobenzamides caused the annulation.

Transition Metal-free Approach for the Synthesis of 2-substituted Quinazolin-4(3H)-one via Anhydrous Magnesium Perchlorate

Background:A convenient and efficient methodology for the synthesis of quinazolin- 4(3H)-ones from simple and readily available 2-amino benzamides and aromatic aldehydes in ethanol using Magnesium perchlorate are being reported in the present study. Good to excellent isolated yields (68-95%) of the corresponding 2-substituted quinazolinones were obtained under mild reaction conditions with excellent functional group tolerance. The affordability of the catalyst, the wide availability of the starting materials, transition metal free synthesis and the simplicity of the procedure renders the present methodology useful in organic synthesis.Objective:A maneuver methodology developed for the synthesis of quinazolin-4(3H)-ones via using Magnesium perchlorate from 2-amino benzamides and aromatic aldehydes in ethanol.Methods:10% mol anhydrous Magnesium perchlorate in presence of ethanol give to simply rapid formation of Quinazolin-4(3H)-ones from 1 mole of 2-amino benzamides and 1 mole of aromatic aldehydes.Results:Screening results of Anti-leishmanial showed that out of the synthesized series of 12 compounds, compounds 3c, 3d, 3g, 3h and 3i showed significant antileishmanial activities (L. donavani) with IC50 values 8.39, 9.37, 9.43, 7.1 and 8.7 μM.Conclusion:In summary, we have developed convenient synthesis of quinazolin-4(3H)-one, from simple and easily available precursor employing anhydrous Mg(ClO4)2 under green conditions.

Pd-Catalyzed Carbonylation-cyclization of N′-(2-bromophenyl)benzamidines by Chloroform as a CO Precursor for the Synthesis of Quinazolin- 4(3H)-ones

We present an efficient method for the synthesis of quinazolin-4(3H)-ones via Pdcatalyzed carbonylation-cyclization of N′-(2-bromophenyl)benzamidines. Chloroform cleanly generated CO under mild conditions. This method allows for the carbonylation-cyclization of N′-(2- bromophenyl)benzamidines in the presence of Pd(OAc)2 to give quinazolin-4(3H)-ones in good to excellent yields.

Resolving the Mystery of Ring Opening in the Synthesis of Benzo[d][1, 3]oxazin-4-one and Quinazolin-4(3H)-one

Quinazoline is the six-membered heterocyclic ring system reported for its versatile biological activities. This characteristic feature of quinazoline makes it a good template for a lead generation library. Ring opening is one of the major concerns in the synthesis of quinazolin-4(3H)-one that results in diamide formation. Here, alternative fusion strategy is reported, which is a time-saving and costeffective method to overcome the ring opening problem associated with the synthesis of benzo[ d][1,3]oxazin-4-one and quinazolin-4(3H)-one.

Synthesis of Quinazolin-4(3H)-ones via the Reaction of 2-Halobenzamides with Nitriles

This paper describes a convenient method to synthesize quinazolin-4(3 H)-ones from simple and readily available 2-halobenzamides and nitriles. The Lewis acid Cu-catalyzed nucleophilic addition of 2-halobenzamide to nitriles followed by SNAr reaction proceeds smoothly in the presence of tBuOK as a base to produce quinazolinone derivatives.

ChemInform Abstract: Palladium‐Catalyzed One‐Pot Synthesis of Quinazolinones via tert‐Butyl Isocyanide Insertion.

A novel palladium-catalyzed three-component reaction for the synthesis of quinazolin-4(3H)-ones from readily available 2-aminobenzamides and aryl halides via a palladium-catalyzed isocyanide insertion/cyclization sequence has been developed. This methodology efficiently constructs quinazolin-4(3H)-ones in moderate to excellent yields with the advantages of operational simplicity.

Ecofriendly Synthesis of Quinazolin‐4(3H)‐ones.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis of quinazolin-4(3H)-ones and 1,2-dihydroquinazolin-4(3H)-ones with the aid of a low-valent titanium reagent

A short and facile synthesis of a series of quinazolin-4(3H)-ones and 1,2-dihydroquinazolin-4(3H)-ones was accomplished in good yields via the novel reductive cyclization of o-nitrobenzamides and triethyl orthoformate, aldehydes or ketones promoted by TiCl4/Zn.

Synthesis of Quinazolin-4-(3h)-ones from O-Amidobenzonitriles Using Urea-hydrogen Peroxide1

Synthesis of quinazolin-4-(3H)-ones from o-amidobenzonitriles has been carried out by using urea-hydrogen peroxide as a mild, stable and non-hazardous reagent.