- Fungal Dioxygenase AsqJ Is Promiscuous and Bimodal: Substrate-Directed Formation of Quinolones versus Quinazolinones
-
Previous studies showed that the FeII/α-ketoglutarate dependent dioxygenase AsqJ induces a skeletal rearrangement in viridicatin biosynthesis in Aspergillus nidulans, generating a quinolone scaffold from benzo[1,4]diazepine-2,5-dione substrates. We report that AsqJ catalyzes an additional, entirely different reaction, simply by a change in substituent in the benzodiazepinedione substrate. This new mechanism is established by substrate screening, application of functional probes, and computational analysis. AsqJ excises H2CO from the heterocyclic ring structure of suitable benzo[1,4]diazepine-2,5-dione substrates to generate quinazolinones. This novel AsqJ catalysis pathway is governed by a single substituent within the complex substrate. This unique substrate-directed reactivity of AsqJ enables the targeted biocatalytic generation of either quinolones or quinazolinones, two alkaloid frameworks of exceptional biomedical relevance.
- Einsiedler, Manuel,Jamieson, Cooper S.,Maskeri, Mark A.,Houk, Kendall N.,Gulder, Tobias A. M.
-
p. 8297 - 8302
(2021/03/01)
-
- Visible light induced tandem reactions: An efficient one pot strategy for constructing quinazolinones using in-situ formed aldehydes under photocatalyst-free and room-temperature conditions
-
A facile tandem route has been developed for constructing quinazolinones from various aminobenzamides and in-situ generated aldehydes. Visible light was found to play a dual role: first oxidizes the alcohol to the aldehyde and then facilitates its cyclization with o-substituted aniline. Furthermore, alcohols are perfect alternatives to aldehydes because they are greener, more available, more economical, more stable, and less toxic than aldehydes. The first reaction step continuously provides material for the second step, which effectively reduces loss through volatilization, oxidation, and polymerization of the aldehyde, while avoiding its toxicity. A variety of quinazolinones can be prepared in the presence of visible light without any additional photocatalyst. The developed synthesis protocol proceeds with the merits of mild conditions, broad substrate scope, operational simplicity, and high atom efficiency, with an eco-energy source under metal-free, photocatalyst-free, and ambient conditions.
- Xie, Zongbo,Lan, Jin,Zhu, Haibo,Lei, Gaoyi,Jiang, Guofang,Le, Zhanggao
-
supporting information
p. 1427 - 1431
(2020/11/02)
-
- Synthesis of 2-aryl quinazolinones: Via iron-catalyzed cross-dehydrogenative coupling (CDC) between N-H and C-H bonds
-
Herein, we describe the direct synthesis of quinazolinones via cross-dehydrogenative coupling between methyl arenes and anthranilamides. The C-H functionalization of the benzylic sp3 carbon is achieved by di-t-butyl peroxide under air, and the subsequent amination-aerobic oxidation process completes the annulation process. Iron catalyzed the whole reaction process and various kinds of functional groups were tolerated under the reaction conditions, providing 31 examples of 2-aryl quinazolinones using methyl arene derivatives in yields of 57-95percent. The synthetic potential has been demonstrated by the additional synthesis of aryl-containing heterocycles. This journal is
- Jang, Yoonkyung,Lee, Seok Beom,Hong, Junhwa,Chun, Simin,Lee, Jeeyeon,Hong, Suckchang
-
supporting information
p. 5435 - 5441
(2020/08/03)
-
- Quinazolin-4(3H)-ones and 5,6-dihydropyrimidin-4(3H)-ones from β-aminoamides and orthoesters
-
Quinazolin-4(3H)-ones have been prepared in one step from 2-aminobenzamides and orthoesters in the presence of acetic acid. Simple 2-aminobenzamides were easily converted to the heterocycles by refluxing in absolute ethanol with 1.5 equivalents of the orthoester and 2 equivalents of acetic acid for 12–24 h. Ring-substituted and hindered 2-aminobenzamides as well as cases incorporating an additional basic nitrogen required pressure tube conditions with 3 equivalents each of the orthoester and acetic acid in ethanol at 110?C for 12–72 h. The reaction was tolerant towards functionality on the benzamide and a range of structures was accessible. Workup involved removal of the solvent under vacuum and either recrystallization from ethanol or trituration with ether-pentane. Several 5,6-dihydropyrimidin-4(3H)-ones were also prepared from 3-amino-2,2-dimethylpropionamide. All products were characterized by melting point, FT-IR, 1H-NMR, 13C-NMR, and HRMS.
- Gavin, Joshua T.,Annor-Gyamfi, Joel K.,Bunce, Richard A.
-
-
- Palladium-catalyzed four-component carbonylative synthesis of 2,3-disubstituted quinazolin-4(3H)-ones: Convenient methaqualone preparation
-
A palladium-catalyzed four-component carbonylative cyclization reaction for the synthesis of 2,3-disubstituted quinazolin-4(3H)-ones has been developed. A range of different 2,3-disubstituted quinazolin-4(3H)-one derivatives were prepared in moderate to good yields employing simple and readily accessible 2-iodoanilines, nitro compounds and acid anhydrides as the synthetic precursors. Mo(CO)6 acted both as a solid CO source and a reductant. Notably, methaqualone as a sedative and hypnotic medication can be prepared easily in 68% yield (4b) under our conditions as well.
- Peng, Jin-Bao,Geng, Hui-Qing,Wang, Wei,Qi, Xinxin,Ying, Jun,Wu, Xiao-Feng
-
-
- Metal-free oxidative cyclization of 2-amino-benzamides, 2-aminobenzenesulfonamide or 2-(aminomethyl)anilines with primary alcohols for the synthesis of quinazolinones and their analogues
-
A general metal-free oxidative cyclization process has been developed for the synthesis of quinazolinones, benzothiadiazines and quinazolines. By this protocol, a range of substituted 2-aminobenzamides, 2-aminobenzenesulfonamide and 2-(aminomethyl)anilines react with various alcohols, leading to the desired annulated products smoothly. This protocol features many advantages as broad substrate scope, mild reaction conditions, low environmental pollution, high atom-economy and good to excellent yields.
- Sun, Jinwei,Tao, Tao,Xu, Dan,Cao, Hui,Kong, Qinggang,Wang, Xinyu,Liu, Yun,Zhao, Jianglin,Wang, Yi,Pan, Yi
-
p. 2099 - 2102
(2018/05/04)
-
- Expeditious synthesis and spectroscopic characterization of 2-methyl-3-substituted-quinazolin-4(3H)-one derivatives
-
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, 1H-NMR, 13C-NMR and DEPT-135 as well as analytical data.
- Ajani, Olayinka O.,Audu, Oluwatosin Y.,Germann, Markus W.,Bello, Babatunde L.
-
p. 562 - 574
(2017/05/26)
-
- A facile synthesis of quinazolinone derivatives through Vilsmeier intermediate
-
The reaction of ethyl 2-aminobenzoate with different substituted amide compounds led to cyclization through Vilsmeier intermediate in dry dichloromethane and ambient temperature, affording the 4(3H)-quinazolinone derivatives with higher yields. The struct
- Mohammed, Shireen,Khalid, Maher
-
-
- Phosphorous acid functionalized polyacrylonitrile fibers with a polarity tunable surface micro-environment for one-pot C-C and C-N bond formation reactions
-
The preparation and application of fiber catalysts have attracted much attention. However, research on the effect of the micro-environment of fiber catalysts on the catalytic activities though of special importance is limited. In this work, a novel strategy for the synthesis of phosphoric acid-functionalized polyacrylonitrile fibers with a polarity tunable surface micro-environment by hydrophobic groups for one-pot C-C and C-N bond formation reactions is reported. The special hydrophobic surface micro-environment of the fiber catalysts is proven to promote the catalytic activities impressively in cyclocondensation of β-ketoesters with 2-aminobenzamides, the Knoevenagel condensation as well as the multi-component Biginelli reactions in green solvents. Both the surface synergy of the catalytic sites and hydrophobic auxiliary groups (benzyl or n-butyl) in the surface of fiber catalysts and interface acceleration in reaction medium play an important role in the highly efficient promotion of catalytic activity. Thereby a surface synergistic mechanism is proposed to explain the micro-environment effect. In addition, the fiber catalysts could be simply separated from the reaction system using tweezers and directly used in the next cycle without further treatment. Importantly, even after 10 reaction cycles in water or ethanol, there is no significant loss in their catalytic activity. The results indicate that the phosphoric acid functionalized fibers show green and sustainable potential for industrial production.
- Xu, Gang,Wang, Lu,Li, Mengmeng,Tao, Minli,Zhang, Wenqin
-
supporting information
p. 5818 - 5830
(2017/12/26)
-
- A quinazoline compound and its synthesis method
-
The invention discloses a synthetic method of a quinazolinone compound. The method can be used for preparing the quinazolinone compound by carrying out reaction at a proper temperature and time by taking a 2-aminobenzamide derivative and a 1, 3-diketone compound as raw materials, taking chiral Bronsted acid or Lewis acid as a catalyst and water and biodegradable ethyl lactate and polyethylene glycol as a mixed solvent. The synthetic method of the quinazolinone compound provided by the invention is mild in reaction condition, low in cost, environment-friendly, high in yield and suitable for industrial production.
- -
-
Paragraph 0096-0107
(2017/11/16)
-
- FeCl3-catalyzed tandem condensation/intramolecular nucleophilic addition/C-C bond cleavage: A concise synthesis of 2-substitued quinazolinones from 2-aminobenzamides and 1,3-diketones in aqueous media
-
A concise approach for the synthesis of 2-substituted quinazolinones using an iron-catalyzed tandem reaction of 2-aminobenzamides with acyclic or cyclic 1,3-diketones via condensation, intramolecular nucleophilic addition, C-C bond cleavage in an aqueous solution of poly(ethylene glycol) under oxidant-free conditions has been developed.
- Shen, Guanshuo,Zhou, Haifeng,Sui, Yuebo,Liu, Qixing,Zou, Kun
-
supporting information
p. 587 - 590
(2016/01/20)
-
- Metal- and Oxidant-Free Synthesis of Quinazolinones from β-Ketoesters with o-Aminobenzamides via Phosphorous Acid-Catalyzed Cyclocondensation and Selective C-C Bond Cleavage
-
A general and efficient phosphorous acid-catalyzed cyclocondensation of β-ketoesters with o-aminobenzamides via selective C-C bond cleavage leading to quinazolinones is developed. This reaction proceeds smoothly under metal- and oxidant-free conditions, giving both 2-alkyl- and 2-aryl-substituted quinazolinones in excellent yields. This strategy can also be applied to the synthesis of other N-heterocycles, such as benzimidazoles and benzothiazoles.
- Li, Zhongwen,Dong, Jianyu,Chen, Xiuling,Li, Qiang,Zhou, Yongbo,Yin, Shuang-Feng
-
p. 9392 - 9400
(2015/10/12)
-
- Br?nsted acid-catalyzed selective C-C bond cleavage of 1,3-diketones: A facile synthesis of 4(3H)-quinazolinones in aqueous ethyl lactate
-
A facile and green approach was developed for the synthesis of 4(3H)-quinazolinones by using camphorsulfonic acid as a catalyst in an aqueous solution of biodegradable ethyl lactate. Various 2-aryl-, 2-alkyl-, and 2-(4-oxoalkyl)quinazolinones were obtained by cyclization of 2-aminobenzamides with a wide range of acyclic or cyclic 1,3-diketones via C-C bond cleavage in satisfactory to excellent yields.
- Shen, Guanshuo,Zhou, Haifeng,Du, Peng,Liu, Sensheng,Zou, Kun,Uozumi, Yasuhiro
-
p. 85646 - 85651
(2015/11/03)
-
- Copper-catalyzed benzylic C(sp3)-H alkoxylation of heterocyclic compounds
-
We achieved intra- and intermolecular C(sp3)-H alkoxylation of benzylic positions of heteroaromatic compounds using CuBrn (n = 1, 2)/5,6-dimethylphenanthroline (or 4,7-dimethoxyphenanthroline) and ( tBuO)2 as a
- Takemura, Noriaki,Kuninobu, Yoichiro,Kanai, Motomu
-
supporting information
p. 2528 - 2532
(2014/04/17)
-
- Metal-free aerobic oxidative C-N bond cleavage of tertiary amines for the synthesis of N-heterocycles with high atom efficiency
-
An efficient metal-free aerobic oxidative C-N bond cleavage of tertiary amines has been developed to construct N-heterocycles using molecular oxygen as the sole oxidant with high atom efficiency, in which all of the three alkyl groups in tertiary amines can be utilized and transformed into N-heterocycles. This journal is the Partner Organisations 2014.
- Chen, Xiuling,Chen, Tieqiao,Zhou, Yongbo,Han, Daoqing,Han, Li-Biao,Yin, Shuang-Feng
-
supporting information
p. 3802 - 3807
(2014/06/09)
-
- KAl(SO4)2·12H2O (Alum) catalyzed one-pot three-component synthesis of 2-alkyl and 2-aryl-4(3H)-quinazolinone under microwave irradiation and solvent free conditions
-
Twenty 2,3-disubstituted-4(3H)-quinazolinones were synthesed by one-pot three-component method with isatoic anhydride, orthoesters and amines as raw materials in the presence of KAl(SO4)2·12H 2O (Alum) under microwave irradiation and solvent-free conditions. 6-Bromo-2-propyl-3-p-tolylquinazolin-4(3H)-one (4m), 6-bromo-2-methyl-3- phenethylquinazolin-4(3H)-one (4n) and 6-bromo-2-ethyl-3-phenethylquinazolin- 4(3H)-one (4o) were characterized by IR, 1H NMR, 13C NMR and elemental analysis. Twenty 2,3-disubstituted-4(3H)-quinazolinones were synthesed by one-pot three-component method with isatoic anhydride, orthoesters and amines as raw materi-als in the presence of KAl(SO4) 2·12H2O (Alum) under microwave irradiation and solvent-free conditions. 6-Bromo-2-propyl-3-p-tolylquinazolin-4(3H)-one (4m), 6-bromo-2-methyl-3-phenethylquinazolin-4(3H)-one (4n) and 6-bromo-2-ethyl-3- phenethylquina-zolin-4(3H)-one (4o) were characterized by IR, 1H NMR, 13C NMR and elemental analysis. Copyright
- Mohammadi, Ali A.,Sadat Hossini
-
experimental part
p. 1982 - 1984
(2012/06/04)
-
- N3-Alkylation during formation of quinazolin-4-ones from condensation of anthranilamides and orthoamides
-
Dimethylformamide dimethylacetal (DMFDMA) is widely used as a source of electrophilic one-carbon units at the formate oxidation level; however, electrophilic methylation with this reagent is previously unreported. Reaction of anthranilamide with DMFDMA at 150 °C for short periods gives mainly quinazolin-4-one. However, prolonged reaction with dimethylformamide di(primary-alkyl)acetals leads to subsequent alkylation at N3. 3-Substituted anthranilamides give 8-substituted 3-alkylquinazolin-4-ones. Condensation of anthranilamides with dimethylacetamide dimethylacetal provides 2,3-dimethylquinazolin-4-ones. In these reactions, the source of the N 3-alkyl group is the O-alkyl group of the orthoamides. By contrast, reaction with the more sterically crowded dimethylformamide di(isopropyl)acetal diverts the alkylation to the oxygen, giving 4-isopropoxyquinazolines, along with N3-methylquinazolin-4-ones where the methyl is derived from N-Me of the orthoamides. Reaction of anthranilamide with the highly sterically demanding dimethylformamide di(t-butyl)acetal gives largely quinazolin-4-one, whereas dimethylformamide di(neopentyl)acetal forms a mixture of quinazolin-4-one and N3-methylquinazolin-4-one. The observations are rationalised in terms of formation of intermediate cationic electrophiles (alkoxymethylidene-N,N-dimethylammonium) by thermal elimination of the corresponding alkoxide from the orthoamides. These are the first observations of orthoamides as direct alkylating agents.
- Nathubhai, Amit,Patterson, Richard,Woodman, Timothy J.,Sharp, Harriet E. C.,Chui, Miranda T. Y.,Chung, Hugo H. K.,Lau, Stephanie W. S.,Zheng, Jun,Lloyd, Matthew D.,Thompson, Andrew S.,Threadgill, Michael D.
-
experimental part
p. 6089 - 6099
(2011/10/08)
-
- Polycyclic N-heterocyclic compounds. Part 601): Reactions of 3-(2-cyanophenyl)quinazolin-4(3H)-ones with primary amines
-
The reaction of 3-(2-cyanophenyl)quinazolin-4(3H)-one with various primary alkylamines gave 3-alkylquinazolin-4(3H)-ones via an addition of the nucleophile, ring opening, and ring closure (ANRORC) mechanism. This type of reaction required hydroxy group fu
- Okuda, Kensuke,Tagata, Tsuyoshi,Kashino, Setsuo,Hirota, Takashi,Sasaki, Kenji
-
experimental part
p. 1296 - 1299
(2010/05/02)
-
- Copper(I) iodide catalyzed domino process to quinazolin-4(3H)-ones
-
An efficient synthesis of substituted quinazolin-4(3H)-ones by a one-pot ligand-free CuI-catalyzed coupling/condensative cyclization under mild conditions is described. Our study provides an alternative strategy for the preparation of biologically active quinazolin-4(3H)-ones. Georg Thieme Verlag Stuttgart.
- Zhou, Jing,Fu, Liangbing,Lv, Man,Liu, Jinsong,Pei, Duanqing,Ding, Ke
-
experimental part
p. 3974 - 3980
(2009/05/27)
-
- Rapid synthesis of 2,3-disubstituted-quinazolin-4-ones enhanced by microwave-assisted decomposition of formamide
-
An efficient methodology for the preparation of a series of 2,3-disubstituted-quinazolin-4(3H)-ones is described via a three step reaction from anthranilic acid. The obtained results also reveal that microwave-assisted rapid decomposition of formamide under controlled conditions of power, temperature and time is a very convenient source of ammonia for the synthesis of 2-substituted-quinazolin-4(3H)-ones and other rings.
- Kostakis, Ioannis K.,Elomri, Abdelhakim,Seguin, Elisabeth,Iannelli, Mauro,Besson, Thierry
-
p. 6609 - 6613
(2008/03/12)
-
- One-pot synthesis of mono- and disubstituted (3H)-quinazolin-4-ones in dry media under microwave irradiation
-
AlCl3/ZnCl2 mixture supported on silica gel is an efficient medium for one-pot synthesis of (3H)-quinazolin-4-ones in the absence of solvent under microwave irradiation or classical heating. The reaction of orthoesters with 2-aminobenzamides ends up with the formation of monosubstituted (3H)-quinazolin-4-ones. One-pot synthesis of disubstituted (3H)-quinazolin-4- ones is also achieved by the reaction of isatoic anhydride with primary amines and orthoesters.
- Dabiri, Minoo,Salehi, Peyman,Mohammadi, Ali A.,Baghbanzadeh, Mostafa
-
p. 279 - 287
(2007/10/03)
-
- QUINAZOLINONE COMPOUNDS AS CALCILYTICS
-
Various calcilytic compounds and pharmaceutical compositions containing these compounds are disclosed. Calcilytic compounds are compounds capable of inhibiting calcium receptor activity. Techniques which can be used to obtain calcilytic compounds and uses of calcilyitc compounds as calcium receptor antagonists are also disclosed.
- -
-
-
- Synthesis of 2-quinazolinonyl imidazolidinones
-
2-Chloromethyl-3-methylquinazolin-4(3H)-one 1 is converted to the azide 4 which easily undergoes cyclisation to give 2-quinazolinonyl imidazolidinones 5. The azides, however, yield 2,3-dimethylquinazolin-4(3H)-one 6 and/or 2-aryl-aminomethyl-3-methylquina
- Reddy,Reddy, P. Pratap,Vasantha
-
p. 393 - 396
(2007/10/03)
-
- Transition-Metal Complex-Catalyzed Reductive N-Heterocyclization: Synthesis of 4(3H)-Quinazolinone Derivatives from N-(2-Nitrobenzoyl)amides
-
Several ruthenium and platinum complexes smoothly catalyze the reductive N-heterocyclization of N-(2-nitrobenzoyl)amides under carbon monoxide pressure to afford the corresponding 4(3H)-quinazolinone derivatives, including some quinazolinone alkaloids, in
- Akazome, Motohiro,Kondo, Teruyuki,Watanabe, Yoshihisa
-
p. 310 - 312
(2007/10/02)
-
- 4(3H)-Quinazolinones from the reaction of N-arylnitrilium salts with isocyanates
-
N-Arylnitrilium salts 1 react with isocyanates 2 to give salts 3 of 4(3H)-quinazolinones 4, from which compounds 4 can be obtained with base. A metathesis of an isocyanate with a nitrilium salt is reported.
- Al-Talib,Jochims,Hamed,Wang,Ismail
-
p. 697 - 701
(2007/10/02)
-
- A NEW ROUTE TO QUINAZOLINONES VIA INTRAMOLECULAR AZA-WITTIG REACTION
-
Treatment of the imide derivatives 1 and 3 readily obtainable from 2-azidobenzoyl chloride and the corresponding amide derivatives with triphenylphosphine or tributylphosphine in xylene at room temperature gave quinazolinones 2 and 4 in excellent yields v
- Takeuchi, Hisato,Eguchi, Shoji
-
p. 3313 - 3314
(2007/10/02)
-
- A NEW EFFICIENT SYNTHESIS OF IMIDAZOLINONES AND QUINAZOLINONE BY INTRAMOLECULAR AZA-WITTIG REACTION
-
A new synthesis of imidazolinones and quinazolinones by intramolecular aza-Wittig reaction is described.Readily available azido substituted imides 4, 6, 10, and 12 reacted with triphenylphosphine or tributylphosphine to afford the corresponding imidazolin
- Takeuchi, Hisato,Hagiwara, Satoshi,Eguchi, Shoji
-
p. 6375 - 6386
(2007/10/02)
-
- Synthesis and Rearrangement of 4-Imino-4H-3,1-benzoxazines
-
N-Acylanthranilamides react with dibromotriphenylphosphorane in the presence of triethylamine as HBr captor to give 4-imino-4H-3,1-benzoxazines in good yields.If the reaction is carried out without acid acceptor, N-acetylanthranilamides yield 2-methyl-4-q
- Mazurkiewicz, Roman
-
p. 973 - 980
(2007/10/02)
-
- One-Pot Synthesis of 2,3-Disubstituted Quinazolin-4-ones
-
Whereas the condensation of N-acetylanthranilic acid (1a) with methyl and phenyl isothiocyanates (2) affords the corresponding 3-substituted 2-methylquinazolin-4-ones (7, R1=Me), N-benzoylanthranilic acid (1b) reacts with these isothiocyanates to give 2-phenyl-3,1-benzoxazin-4-one (5b: R1=Ph) and N-substituted o-benzoylaminobenzamide (6: R1=R2=Ph), respectively.
- Ashare, Ram,Mukerjee, Arya K.
-
p. 1180 - 1181
(2007/10/02)
-
- Functionalization of 2-Methyl-3-o-tolyl-4(3H)-quinazolinone and Related Compounds through Carbanion Reactions at the 2-Methyl Group
-
2-Methyl-3-o-tolyl-4(3H)-quinazolinone (methaqualone, 3a), 2,3-dimethyl-4(3H)-quinazolinone (3b), and 2-methyl-3-phenyl-4(3H)-quinazolinone (3c) were converted to the 2-lithiomethyl derivatives 4a, 4b, and 4c, respectively, by means of lithium diisopropylamide in THF-hexane at 0 deg C.Reactions of 4a-c with a series of electrophilic reagents led to elaboration at the original 2-methyl group.Thus, 4a was alkylated with methyl iodide, allyl bromide, and ethyl bromide, sulfenylated with diphenyl disulfide, and condensed with benzaldehyde and cyclohexanone.Although 4a failed to react with benzophenone and showed a preference for enolization with acetone and butanone, the less hindered salt 4b added readily to the carbonyl group of benzophenone and acetone.Lithio salt 4c underwent self-condensation on treatment with cyclohexanone.Photostimulated phenylation of 2-potassiomethyl derivative of 3a was effected with iodobenzene.Lateral acylation of 3a was accomplished with esters of aliphatic and aromatic acids in the presence of excess sodium hydride.
- Rathman, Terry L.,Sleevi, Mark C.,Krafft, Marie E.,Wolfe, James F.
-
p. 2169 - 2176
(2007/10/02)
-
- Phosphoramides. XIII. Phosphorus Pentaoxide-Amine Hydrochloride Mixtures as Reagents in the Synthesis of 4(3H)-Quinazolinones and 4-Quinazolinamines
-
4(3H)-Quinazolinones 3a-r have been prepared by heating methyl N-acylanthranilates 1a-c and the hydrochlorides of primary aliphatic and aromatic amines with phosphorus pentaoxide and N,N-dimethylcyclohexylamine at 180 deg C. 4-Quinazolinamines 4 and the amidine 7 were isolated as by-products.The carboxamides 5 and 6 were believed to be reaction intermediates.By raising the temperature to 250 deg C 4 was obtained in a preparative yield.
- Nielsen, Knud Erik,Pedersen, Erik B.
-
p. 637 - 642
(2007/10/02)
-