Results 81 to 90 of about 2,756 (214)

Synthesis of benzofurans and benzopyrans

, 2002
Syntheses of 2,3-dihydrobenzofurans and 3,4-dihydrobenzopyrans normally involve several stages, therefore efficient syntheses of these compounds are desirable. A number of 3,4-dihydrobenzopyrans derivatives were prepared in one pot syntheses. The reaction is thought to proceed through cation intermediates, involving allylic cations generated by the ...
openaire   +2 more sources

Safety and Efficacy of Direct Oral Anticoagulants Versus Vitamin K Antagonists for Cerebrovascular Ischemic Outcomes in Non‐Valvular Atrial Fibrillation: A Systematic Review and Meta‐Analysis

Clinical Cardiology, Volume 49, Issue 4, April 2026.
Direct Oral Anticoagulants (DOACs) were associated With lower rates of cerebrovascular ischemic events and major bleeding compared With Vitamin K antagonists in non‐valvular atrial fibrillation, With similar mortality. These findings support DOACs as the preferred anticoagulant strategy for stroke prevention in contemporary clinical practice.
Anam Nasir, Naqash Anwar, Abdullah Bin Kamran, Ayesha Muhammad, Ali Haider, Muhammad Mubashar, Fatima Tariq, Mostafa Helou, Besher Shami   +8 more
wiley   +1 more source

Synthesis of Benzopyrans by Pd(II)- or Ru(II)-Catalyzed C–H Alkenylation of 2‑Aryl-3-hydroxy-2-cyclohexenones

, 2016
2-Aryl-3-hydroxy-2-cyclohexenones are shown to be competent substrates for palladium- and ruthenium-catalyzed C–H alkenylation reactions with terminal alkenes, providing, in most cases ...
Hon Wai Lam (1932658), Martin D. Wieczysty (1997788), Imtiaz Khan (1997791), Suresh Reddy Chidipudi (1932661)   +3 more
core   +1 more source

Heteroaromatization with 4-Hydroxycoumarin Part II: Synthesis of Some New Pyrano[2,3-d]pyrimidines, [1,2,4]triazolo[1,5-c]pyrimidines and Pyrimido[1,6-b]-[1,2,4]triazine Derivatives

Molecules, 2001
A variety of novel [1,2,4]triazolo[1,5-c]pyrimidine-13-ones (4a-f) and (5b-d) could be obtained via reaction of 9-amino-7-(4’-chlorophenyl)-8,9-dihydro-8-imino-6H,7H-[1]benzopyrano[3`,4`:5,6]pyrano[2,3-d]pyrimidine-6-one (3) with a variety of ...
A. H. Bedair, A. H. Fakery, N. A. El-Hady, M. S. Abd El-Latif, A. M. El-Agrody   +4 more
doaj   +1 more source

Asymmetric Roadmap to Diverse Polycyclic Benzopyrans via Phosphine-Catalyzed Enantioselective [4 + 2]-Annulation Reaction

, 2016
The catalytic addition of the amino acid derived bifunctional N-acylamino­phosphine to an α-substituted allene ester generated a zwitterionic dipole that engaged the vinylogous ester function of 3-cyano-chromones in a [4 + 2] annulation reaction to ...
Carsten Strohmann (1307016), Adithi Danda (2744476), Golz, C., Kamal Kumar, Kamal Kumar (91852), Naredla, K., Carsten Strohmann, Danda, A., Christopher Golz (1528303), Kumar, K., Strohmann, C., Naredla Kesava-Reddy (2744479), Christopher Golz, Naredla Kesava-Reddy, Adithi Danda   +14 more
core   +2 more sources

Synthesis and Chemical Properties of 3-Phosphono-coumarins and 1,2-Benzoxaphosphorins as Precursors for Bioactive Compounds

Molecules, 2019
Coumarins are an important class of natural heterocyclic compounds that have attracted considerable synthetic and pharmacological interest due to their various biological activities.
Ana I. Koleva, Nevena I. Petkova-Yankova, Rositca D. Nikolova   +2 more
doaj   +1 more source

Sc(OTf)₃-catalyzed diastereoselective synthesis of 3,4-dihydro-4-amino-2H-1-benzopyrans

, 2001
2,2-Dimethoxypropane reacts with a variety of o-hydroxybenzaldimines in the presence of a catalytic amount of scandium triflate at ambient temperature to afford a series of new compounds, 3,4-dihydro-4-amino-2-methoxy-2-methyl-2H-1-benzopyrans, in high ...
Chandra Sekhar, K., Geetha, V., Yadav, J. S., Subba Reddy, B. V.   +3 more
core   +1 more source

Trifluoroacetic acid-mediated facile transformation of 2-C-hydroxymethyl-D-glycals to chiral pyrano[2,3-b]benzopyrans

, 2009
Treatment of 2-C-hydroxymethyl-D-glycals with phenols in trifluoroacetic acid at ambient temperature leads to an extremely facile transformation affording chiral pyrano[2,3-b]benzopyrans in high ...
Santhi, Meenakshisundaram, Bhagavathy, Shanmugasundaram, Balasubramanian, Kalpattu K.   +2 more
core   +1 more source

Electron impact induced cyclizations in 4-chioro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans

, 1987
Intramolecular substitutions leading to cyclizations with the ejection of chlorine have been noticed during mass spectral fragmentation of 4-chloro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans.
Balasubramanian, K. K., Ramana, D. V., Srinivas, R., Saiganesh, R., Swaminathan, K.   +4 more
core   +1 more source

Synthesis of 3,4-Disubstituted 2H-Benzopyrans through C−C Bond Formation via Electrophilic Cyclization

, 2016
The electrophilic cyclization of substituted propargylic aryl ethers by I2, ICl, and PhSeBr produces 3,4-disubstituted 2H-benzopyrans in excellent yields.
Tuanli Yao (1340802), Tanay Kesharwani (2368204), Richard C. Larock (1353099), Shilpa A. Worlikar (2333623)   +3 more
core   +2 more sources