An efficient synthesis of 6H,7H-chromeno[4,3-b]chromenes and 6,7-dihydrothio chromeno[3,2-c]chromenes as 9-substituted xanthene like analogs
摘要:
An efficient synthetic route with good overall yields to access 7-aryl/heteroaryl/alkyl substituted 6H,7H-chromeno[4,3-b]chromene, and 6,7-dihydrothiochromeno[3,2-c]chromene scaffolds has been developed. The route to these xanthene-like analogs involves a three-step reaction sequence: (1) Michael addition of readily available phenol and thiophenol to 4-chloro-2,2-dimethyl-2H-chromene-3-carbaldehyde, (2) Grignard reaction of different aryl, heteroaryl and alkyl magnesium bromides on the resulting carbaldehydes followed by (3) FeCl3 catalyzed spontaneous intramolecular Friedel-Craft's reaction on the diarylmethyl carbinols. (C) 2011 Elsevier Ltd. All rights reserved.
Diversity oriented synthesis of chromene-xanthene hybrids as anti-breast cancer agents
作者:M. Srinivas Lavanya Kumar、Jyotsana Singh、Sudipta Kumar Manna、Saroj Maji、Rituraj Konwar、Gautam Panda
DOI:10.1016/j.bmcl.2017.12.065
日期:2018.2
A diverse library of chromene-xanthene hybrids were synthesized through intramolecular Friedel-Crafts reaction of the arenoxy carbinols. Examples include first incorporation of amino acid tyrosine into xanthene skeletons with polar functionalities. A careful structural evaluation revealed that tyrosine crafted chromene-xanthene hybrids exhibited good activities against breast cancer cell lines MCF-7
Synthesis, X-ray Structure, and Pharmacological Activity of Some 6,6-Disubstituted Chromeno[4,3-b]- and Chromeno- [3,4-c]-quinolines
作者:Mohamed I. Hegab、Abdel-Samee M. Abdel-Fattah、Nabil M. Yousef、Hany F. Nour、A. M. Mostafa、Mohey Ellithey
DOI:10.1002/ardp.200700089
日期:2007.8
Some chromeno[4,3‐b]quinolines 4a–i were obtained from β‐chloro carboxyaldehydes 3a–c with different aniline derivatives namely, aniline, 4‐fluoroaniline, and 2‐aminophenol. Surprisingly, 3a–c reacted with 2‐aminothiophenol and afforded the chromeno[3,4‐c]quinoline derivatives 5a–c. Single‐crystal X‐ray diffraction studies of 4e and 5b provided good support for the established structure. Compounds
Halogen-Exchange Fluorination of β-Chlorovinyl Aldehydes - Unexpected Cascade Transformations in the Fluorination of 4-Chloro-2<i>H</i>
-chromene and 4-Chloro-2<i>H</i>
-thiochromene-3-carbaldehydes
One of the most facile and robust ways of incorporating fluorine atoms in organic substrates is through the Halex fluorination. We have described here the Halex fluorination of β‐chlorovinyl aldehydes using KF/DMSO system under mild conditions. Further the transformation of the fluoro‐substituted intermediates to its dimeric compounds via a cascade sequence of six steps is discussed.
4-Chloro-2,2-disubstituted Chromen-3-carboxaldehyde: Synthesis of some Fused Polycyclic Heterocycles as Anti-inflammatory, Analgesic, Anticonvulsant, and Antiparkinsonian Agents
作者:Mohamed I. Hegab、Mohamed M. Abdulla
DOI:10.1002/ardp.200500124
日期:2006.1
Some new aldazino 4, pyrazolo 5, thieno 8, and thiooxopyrimidino chromenes 10 were prepared via reaction of the corresponding β‐chlorocarboxaldehyde 3 with hydrazine hydrate, mercaptoacetic acid, and thiourea, respectively. Wherever, 4‐chlorochromene derivatives 2 along with 4‐chlorochromen‐3‐carboxaldehyde derivatives 3 were prepared from the corresponding ketone 1 with Vilsmeier‐Haack reagent. Some
Microwave assisted [RuCl<sub>2</sub>(p-cymene)<sub>2</sub>]<sub>2</sub> catalyzed regioselective endo-tandem cyclization involving imine and alkyne activation: an approach to benzo[4,5]imidazo[2,1-a]pyridine scaffold
作者:Sudipta Kumar Manna、Gautam Panda
DOI:10.1039/c4ra02581d
日期:——
A microwave assisted efficient route to the synthesis of benzimidazole fused heterocycles through metal catalyzed endo-cyclization strategy involving imine and alkyne activation has been developed.