开发了一种新颖实用的铜催化方法制备5-芳基吲哚并[3,2 - b ]喹唑啉-7(5 H)-ones。通过使等角酸酐与芳基肼反应,可以容易地制备2-氨基-N'-芳基苯并肼。然后,在CuI的存在下,通过2-硝基苯甲醛的缩合/分子内环化反应,以高收率产生了相应的5-芳基吲唑并[3,2 - b ]喹唑啉-7(5 H)-。
A new cascade reaction: concurrent construction of six and five membered rings leading to novel fused quinazolinones
作者:K. Siva Kumar、P. Mahesh Kumar、V. Sreenivasa Rao、Ahamed A. Jafar、Chandana Lakshmi T. Meda、R. Kapavarapu、Kishore V. L. Parsa、Manojit Pal
DOI:10.1039/c2ob25296a
日期:——
A one-pot cascade reaction has been developed leading to the concurrent construction of six and five membered fused N-heterocyclic rings of indazolo[3,2-b]quinazolinones. The methodology involved the reaction of isatoic anhydride, a hydrazine and o-iodo benzaldehyde in the presence of Pd(PPh3)4 and BINAP in MeCN. The mechanism of this cascade reaction is discussed. A variety of indazolo[3,2-b]quinazolinone derivatives were prepared by using this methodology in good yields, some of which were tested for their PDE4 inhibitory properties in vitro. The dose response and docking study performed using a representative compound is presented.
Copper-catalyzed intramolecular C–N bond formation reaction of 3-amino-2-(2-bromophenyl)dihydroquinazolinones: synthesis of indazolo[3,2-b]quinazolinones
A copper-catalyzed intramolecular C-N bond formation reaction of 3-amino-2-(2-bromophenyl)dihydroquinazolinones has been developed for the synthesis of indazolo[3,2-b]quinazolinones in moderate to good yields. The structure of the newly synthesized indazolo[3,2-b]quinazolinones was unambiguously confirmed by X-ray single-crystal diffraction analysis. Moreover, a possible mechanism for the formation of indazolo[3,2-b]quinazolinones is discussed. (C) 2013 Elsevier Ltd. All rights reserved.