Results 31 to 40 of about 3,431 (233)

Pyrans and their Benzo Derivatives: Synthesis [PDF]

, 2008
The abundance of six-membered oxygen containing heterocycles in bioactive natural products continues to encourage the development of new and improved syntheses. There is a vast amount of new literature dedicated to the synthesis of pyrans and their benzo
Gibson, JS, M.A. Brimble, J.S. Gibson, Brimble, Margaret, J. Sperry, Sperry, Jonathan   +5 more
core   +1 more source

Construction of (Dihydro)naphtho[1,8-bc]pyrans via Rh(III)-Catalyzed Twofold C-H Activation of Benzoylacetonitriles [PDF]

, 2018
Rh(III)-catalyzed cascade C-H activation of benzoylacetonitriles and annulation with sulfoxonium ylides was realized, leading to selective synthesis of naphthols, 2,3-dihydronaphtho[1,8-bc]pyrans, and naphtho[1,8-bc]pyrans.
Yang, Shuang, Liu, Bingxian, Shuang Yang, Bingxian Liu, Youwei Xu, Ying Zhang, Zhang, Ying, Hu, Panjie, Li, Xingwei, Panjie Hu, Xu, Youwei, Xingwei Li   +11 more
core   +1 more source

Triphenylphosphine Catalysed Facile Multicomponent Synthesis of 2-Amino-3-Cyano-6-Methyl-4-Aryl-4H-Pyrans [PDF]

Iranian Journal of Chemistry & Chemical Engineering, 2017
Triphenyl phosphine(PPh3), an efficient and reusable catalyst, catalysed the synthesis of 2-amino-3-cyano-6-methyl-4-aryl-4H-pyran-5-ethylcarboxylate derivatives by one-pot condensation of aromatic aldehydes, malononitrile and ethyl acetoacetate in EtOH ...
Harikrishnan Ramadoss, Hamzeh Kiyani, Syed Sheik Mansoor   +2 more
doaj  

Construction of (Dihydro)naphtho[1,8-bc]pyrans via Rh(III)-Catalyzed Twofold C–H Activation of Benzoylacetonitriles [PDF]

, 2018
Rh­(III)-catalyzed cascade C–H activation of benzoylacetonitriles and annulation with sulfoxonium ylides was realized, leading to selective synthesis of naphthols, 2,3-dihydronaphtho­[1,8-bc]­pyrans, and naphtho­[1,8-bc]­pyrans.
Panjie Hu (3902923), Bingxian Liu (2038690), Xingwei Li (1391965), Youwei Xu (4170406), Shuang Yang (64650), Ying Zhang (1235337)   +5 more
core   +1 more source

Synthesis and Utility of 2,2-Dimethyl‑2H‑pyrans: Dienes for Sequential Diels–Alder/Retro-Diels–Alder Reactions [PDF]

, 2019
The practical use of 2,2-dimethyl-2H-pyrans as electron-rich dienes in sequential Diels–Alder/retro-Diels–Alder (DA/rDA) domino processes to generate aromatic platforms has been demonstrated.
Fernando García-Tellado (1724857), Samuel Delgado-Hernández (3206676), Abián Díaz-Díaz (6068549), Raquel Diana-Rivero (6068552), David Tejedor (1724863)   +4 more
core   +1 more source

Neuroprotective Properties and Molecular Mechanisms of Action of 4H-Pyran-Based Acids

Frontiers in Bioscience-Landmark
The development of effective neuroprotective agents remains one of the most urgent and complex challenges in modern medical and biological research, given the increasing prevalence of neurodegenerative diseases and the limited efficacy of existing ...
Alexander Kravtsov, Stanislav Kozin, Rodion Kondratenko, Oksana Lyasota, Anna Dorohova, Olga Leontyeva, Jose Luis Hernandez-Caceres, Stepan Dzhimak   +7 more
doaj   +1 more source

Cu-phthalocyanine Coated Hybrid Magnetic Nanoparticles: Preparation and Application in the Synthesis of Mono- and Bis pyrano[2,3-d]pyrimidinones and mono- and Bis-2-amino-4H-pyrans [PDF]

Iranian Journal of Chemistry & Chemical Engineering, 2020
In this research, Cu-phthalocyanine coated hybrid magnetic nanoparticles have been prepared in a simple method and evaluated as an efficient catalyst in the preparation of mono- and bis-pyrano[2,3-d]pyrimidinones and mono- and bis-2-amino-4H-pyrans from ...
Ali Reza Karimi, Fatemeh Bagherian, Marzie Karimi   +2 more
doaj   +1 more source

Nano-SiO2 catalyzed three-component preparations of pyrano[2,3-d]pyrimidines, 4H-chromenes, and dihydropyrano[3,2-c]chromenes

Journal of Saudi Chemical Society, 2018
An efficient one-pot three-component procedure has been developed for the preparation of tetrahydrobenzo[b]pyrans, dihydropyrano[3,2-c]chromenes, and pyrano[2,3-d]pyrimidines using nano-SiO2 as catalyst in H2O at 70 °C.
Ebrahim Mollashahi, Mohammad Nikraftar
doaj   +1 more source

Convenient One-Pot Synthesis of Spirooxindole-4H-pyrans in the Presence of SBA-Pr-NH2 and Evaluation of their Urease Inhibitory Activities [PDF]

Journal of Nanostructures, 2012
A simple and efficient one-pot three-component synthesis of the biologically important spirooxindole-4H-pyrans was carried out by the reaction of isatin, activated methylene reagents, and 4- hydroxycoumarin in aqueous medium. SBA-Pr-NH2 was found to be
G. Mohammadi Ziarani, N. Hosseini Mohtasham, N. Lashgari, A. Badiei, M. Amanlou, R. Bazl   +5 more
doaj   +1 more source

An efficient three-step synthesis of cyclopenta[b]pyrans via 2-donor-substituted Fischer ethenylcarbenechromium complexes [PDF]

, 2005
A wide range of cyclopenta[b]pyrans 4 has been synthesized in a one-pot reaction by treatment of different 2-donorsubstituted ethenylcarbene-chromium complexes 2 with alkynes in THF in moderate to excellent yields (41-90% for 14 out of 25 examples).
Funke, Frank, Belgardt, T., Schimer, H., de Meijere, Armin, Noltemeyer, M., Stein, F., Duetsch, Michael, Wu, Y., Knieriem, B.   +8 more
core   +1 more source