The Vilsmeier–Haack formylation of 2,3-dihydro-4H-1,3-benzoxazin-4-ones and isomeric 1,2-dihydro-4H-3,1-benzoxazin-4-ones: an effective approach to functionalized 2H-/4H-chromenes and tetrahydroacridines
摘要:
We found that 1,3- and isomeric 3,1-benzoxazin-4-ones react with the Vilsmeier reagent in vastly different ways. Thus, either 2H- or 4H-chromenes were obtained in good yields when 1,3-benzoxazin-4-ones were reacted at 75-80 degrees C, while the formylation of 3,1-benzoxazines at ambient temperature leads to acridine-9-one or 9-chloroacridine derivatives, depending on the amount of Vilsmeier reagent and the nature of substrate. (C) 2015 Elsevier Ltd. All rights reserved.
A facile approach for the synthesis of novel xanthene derivatives with Vilsmeier–Haack reagent
作者:Oleg K. Farat、Ivan V. Ananyev、Svetlana A. Varenichenko、Ekaterina V. Zaliznaya、Victor I. Markov
DOI:10.1007/s10593-019-02416-6
日期:2019.1
A series of new derivatives of formylxanthenes have been synthesized via the reaction of substituted 1,3-benzoxazines with Vilsmeier–Haack reagent. It has been shown that 1,3-benzoxazines unsubstituted in the aromatic part and 6-bromo-1,3-benzoxazines are rearranged into xanthene derivatives under heating at 80°C for 1.5 h. Substitution at the C-8 position of 1,3-benzoxazines, especially with electronegative
Reactions of 2Н(4Н)-chromenes with dinucleophiles: one-step synthesis of 2-(1H-(bi)pyrazol-3-yl)- and 2-(1,4(5)-(benzo)diazepin-4-yl)phenols
作者:Serhii P. Zahorulko、Svetlana А. Varenichenko、Oleg K. Farat、Aleksander V. Mazepa、Sergiy I. Okovytyy、Victor I. Markov
DOI:10.1007/s10593-018-2367-y
日期:2018.9
Novel derivatives of 2-(1H-(bi)pyrazol-3-yl)phenols and 2-(1,4(5)-(benzo)diazepin-4-yl)phenols were obtained in the reaction of (4-amino-2H-chromen-2-ylidene)malondialdehyde and 4H-chromen-4-imines with 1,2-, 1,3-, and 1,4-dinucleophiles proceeding as a cascade reaction initiated by the Michael reaction.
Substituted furochromene compounds of antiinflammatory action
申请人:Mercep Mladen
公开号:US20060148890A1
公开(公告)日:2006-07-06
The present invention relates to novel compounds of the formula (I)
including all stereoisomers and tautomers thereof, to the pharmaceutically acceptable salts and solvates thereof, to the processes and reactive intermediates for their preparation and to their use in the prophylaxis and treatment of asthma and other inflammatory diesases and/or conditions in humans.