18600-53-8Relevant academic research and scientific papers
C2-substituted quinazolinone derivatives exhibit A1 and/or A2A adenosine receptor affinities in the low micromolar range
Pieterse, Lianie,Terre'Blanche, Gisella,van der Walt, Mietha M.
supporting information, (2020/06/08)
Antagonists of the adenosine receptors (A1 and A2A subtypes) are widely researched as potential drug candidates for their role in Parkinson's disease-related cognitive deficits (A1 subtype), motor dysfunction (A2A subtype) and to exhibit neuroprotective properties (A2A subtype). Previously the benzo-α-pyrone based derivative, 3-phenyl-1H-2-benzopyran-1-one, was found to display both A1 and A2A adenosine receptor affinity in the low micromolar range. Prompted by this, the α-pyrone core was structurally modified to explore related benzoxazinone and quinazolinone homologues previously unknown as adenosine receptor antagonists. Overall, the C2-substituted quinazolinone analogues displayed superior A1 and A2A adenosine receptor affinity over their C2-substituted benzoxazinone homologues. The benzoxazinones were devoid of A2A adenosine receptor binding, with only two compounds displaying A1 adenosine receptor affinity. In turn, the quinazolinones displayed varying degrees of affinity (low micromolar range) towards the A1 and A2A adenosine receptor subtypes. The highest A1 adenosine receptor affinity and selectivity were favoured by methyl para-substitution of phenyl ring B (A1Ki = 2.50 μM). On the other hand, 3,4-dimethoxy substitution of phenyl ring B afforded the best A2A adenosine receptor binding (A2AKi = 2.81 μM) among the quinazolinones investigated. In conclusion, the quinazolinones are ideal lead compounds for further structural optimization to gain improved adenosine receptor affinity, which may find therapeutic relevance in Parkinson's disease-associated cognitive deficits and motor dysfunctions as well as exerting neuroprotective properties.
Palladium (0)-catalyzed C(sp2)-H oxygenation with carboxylic acids
Gong, Ai-Jun,Li, Xu-Qin,Vu, Huu-Manh,Yong, Jia-Yuan
supporting information, (2020/02/15)
Palladium (0)-catalyzed Ortho-benzoxylation of the sp2 C–H bond of arylbenzoxazinones with carboxylic acid is reported. With benzoxazinone as directing group, the reaction went smoothly under the benign condition and gave the desired product wi
Recyclable Heterogeneous Palladium-Catalyzed Carbonylative Cyclization of 2-Iodoanilines with Aryl Iodides Leading to 2-Arylbenzoxazinones
Cai, Mingzhong,Huang, Bin,Xu, Zhaotao,Zhou, Zebiao
, p. 581 - 590 (2020/02/13)
A highly efficient and practical heterogeneous palladium-catalyzed carbonylative coupling of 2-iodoanilines with aryl iodides has been developed. The reaction occurs smoothly in toluene at 110 °C with N, N -diisopropylethylamine as base under carbon monoxide (5 bar) and offers a general and powerful tool for the construction of various valuable 2-arylbenzoxazinones with excellent atom-economy, high functional group tolerance, good to high yields, and easy recyclability of the palladium catalyst. The reaction is the first example of heterogeneous palladium-catalyzed carbonylative coupling for the preparation of diverse 2-arylbenzoxazinones from commercially easily available 2-iodoanilines and aryl iodides.
Oxidative NHC catalysis for base-free synthesis of benzoxazinones and benzoazoles by thermal activated NHCs precursor ionic liquid catalyst using air as oxidant
Guan, Jiali,Liu, Wei,Liu, Yuchen,Song, Zhibin,Tao, Duan-Jian,Yan, Jieying,Yuan, Jian-Jun,Zhou, Youkang
, (2020/05/25)
A reusable thermal activated NHC precursor ionic liquid catalyst ([BMIm]2[WO4]) has been prepared and developed for the synthesis of nitrogen-containing heterocycles such as benzoxazinones and benzoazoles through imines activation. [BMIm]2[WO4] exhibited the good activity for the base-free condensation and oxidative NHC catalysis tandem under air atmosphere. The catalyst can be recovered and reused for at least five runs in gram scale synthesis without any decrease in catalytic activity. Furthermore, the control experiments demonstrated that the reaction involved formation of aromatic aldimines, NHC-catalyzed oxidative formation of imidoyl azoliums and intramolecular cyclization to generate the product.
Palladium-Catalyzed Olefination of 4H-Benzo[d][1,3]oxazin-4-one Derivatives with Activated Alkenes via Preferential Cyclic Imine-N-Directed Aryl C-H Activation
Panja, Subir,Maity, Srabani,Majhi, Biju,Ranu, Brindaban C.
, p. 5777 - 5786 (2019/08/30)
A palladium-catalyzed chelation-assisted selective ortho C-H bond olefination of biologically active 4H-benzo[d][1,3] oxazin-4-one derivatives with activated olefins has been achieved. The products are obtained in good yields with high regio- and stereose
One-Pot Synthesis of 2-Arylbenzoxazinones from 2-Arylindoles with (Diacetoxyiodo)benzene as the Sole Oxidant
Shang, Xian-Xing,Vu, Huu-Manh,Li, Xu-Qin
supporting information, p. 377 - 383 (2017/10/30)
A series of synthetically interesting 2-arylbenzoxazinones was prepared from 2-arylindoles by an efficient oxidative reaction mediated by (diacetoxyiodo)benzene [PhI(OAc) 2 ] and assisted by water. PhI(OAc) 2 was used as the sole oxi
Silver-Mediated Synthesis of 4H-Benzoxazin-4-ones by Intramolecular Decarboxylative O-Acylation Reactions with α-Oxocarboxylic Acid
Bharathimohan, Kuppusamy,Ponpandian, Thanasekaran,Jafar, Ahamed A.
, p. 2806 - 2813 (2017/05/29)
The first example of an intramolecular decarboxylative acylation reaction for the synthesis of 4H-benzoxazin-4-one derivatives has been described. The silver-mediated reaction has a broad substrate scope and provides a mild and rapid approach to the corre
Catalytic aza-wittig reaction of acid anhydride for the synthesis of 4H-benzo[d][1,3]oxazin-4-ones and 4-benzylidene-2-aryloxazol-5(4H)-ones
Wang, Long,Xie, Yi-Bi,Huang, Nian-Yu,Yan, Jia-Ying,Hu, Wei-Min,Liu, Ming-Guo,Ding, Ming-Wu
, p. 4010 - 4016 (2016/07/06)
Compared to the aza-Wittig reaction of aldehydes, ketones, amides, and esters, the aza-Wittig reaction of acid anhydride was always overlooked, which should be an important part of Wittig reactions. Here, the aza-Wittig reaction of anhydride and catalytic aza-Wittig reaction of anhydride were both developed with high yields, which provides an efficient method to synthesize of 4H-benzo[d][1,3]oxazin-4-ones and 4-benzylidene-2-aryloxazol-5(4H)-ones. The strategy of copper-catalyzed reduction of phosphine oxide was used and found effective for this transformation. Additionally, the one-pot catalytic aza-Wittig reaction of carboxylic acids was achieved. Furthermore, NMR experiments and Hammett plot recorded the process of catalytic aza-Wittig reaction of anhydride, which provides direct proof that the copper-catalyzed reduction of waste phosphine oxide is the key step in this transformation.
RETRACTED ARTICLE: Palladium-Catalyzed Decarboxylative Selective Acylation of 4H-Benzo[d][1,3]oxazin-4-one Derivatives with α-Oxo Carboxylic acids via Preferential Cyclic Imine-N-Directed Aryl C-H Activation
Majhi, Biju,Kundu, Debasish,Ghosh, Tubai,Ranu, Brindaban C.
, p. 283 - 295 (2016/02/16)
The benzoxazine scaffolds are of much interest as they are found in a large array of natural products and pharmaceutical drugs with diverse activities. We have developed a palladium-catalyzed decarboxylative selective mono- and bis-acylation of 4H-benzo[d
Selective Oxidative Decarbonylative Cleavage of Unstrained C(sp3)-C(sp2) Bond: Synthesis of Substituted Benzoxazinones
Verma, Ajay,Kumar, Sangit
supporting information, p. 4388 - 4391 (2016/10/11)
A transition metal (TM)-free practical synthesis of biologically relevant benzoxazinones has been established via a selective oxidative decarbonylative cleavage of an unstrained C(sp3)-C(sp2) bond employing iodine, sodium bicarbonate, and tbutyl hydroperoxide in DMSO at 95 °C. Control experiments and Density Functional Theory (DFT) calculations suggest that the reaction involves a [1,5]H shift and extrusion of CO gas as the key steps. The extrusion of CO has also been established using PMA-PdCl2.
