Results 41 to 50 of about 51,192 (201)

[DMImd-DMP]: A highly efficient and reusable catalyst for the synthesis of 4H-benzo[b]pyran derivatives

Heterocyclic Communications, 2019
A series of substituted 4H-pyrans derivatives were synthesized by a one-pot, multi-component reaction of aromatic aldehydes, malononitrile, and pyrazolone derivatives or active methylene carbonyl compounds such as dimedone, in the presence of 1,3 ...
Redouane Mohamed Abdenour, Khiri-Meribout Naima, Benzerka Saida, Debache Abdelmadjid   +3 more
doaj   +1 more source

Synthesis of New 2-Substituted 4-(2-Furyl)-4H-pyrans

, 1994
Substituted 2-amino-3-cyano-4H-pyrans represent important precursors in syntheses of condensed heterocycles containing a 4H-pyran nucleus. In the context of studies of reactivity of 2-amino-5-acetyl-4-(5-X-2-furyl)-3-cyano-6-methyl-4H-pyrans we were ...
Dušan Ilavský, Milan Bruncko, Štefan Marchalín, Lubomír Zalibera   +3 more
core   +1 more source

Oxidative Difunctionalization of 2‑Amino‑4H‑pyrans in Iodobenzene Diacetate and N‑Chlorosuccinimide: Reactivity, Mechanistic Insights, and DFT Calculations

, 2016
Oxidative difunctionalization of 2-amino-4H-pyrans was accomplished with iodobenzene diacetate (IBD) and N-chlorosuccinimide (NCS) reagents in alcoholic medium.
Santhosh Reddy Mandha (2015458), Vittal Rao Bommena (2015461), Manjula Alla (2015452), Santosh Kumar Lingala (2015455), Jagadeesh Babu Nanubolu (567973), Soujanya Yarasi (2015449)   +5 more
core   +2 more sources

H5BW12O40 as a green and efficient homogeneous but recyclable catalyst in the synthesis of 4H-Pyrans via multicomponent reaction

, 2022
Keggin-type heteropolyacid, H5BW12O40 (BWA) with a higher negative charge and stronger Brønsted acidity comparing to Si and P derivatives was used as an efficient, green, and reusable catalyst in a three-component reaction involving the cyclocondensation
Vahideh Zadsirjan (6272597), Seyed Yahya Shirazi Beheshtiha (556375), Majid Mommahed Heravi (9225485), Masoud Mirzaei (1645132), Fatemeh Mashayekh Ameli (11992726), Maryam Bazargan (10588409)   +5 more
core   +1 more source

A Facile One-Pot and Green Multi-Component Synthesis of 2-Amino-4H-pyrans Promoted by Pyridinium p-Toluenesulfonate in Aqueous Medium [PDF]

, 2016
International audienceBackground: 4H-benzo[b] pyran derivatives have attracted great interest due to biological and pharmacological properties including antimicrobial, antiviral, antipro liferative, sex pheromone, antitumor, cancer therapy, central ...
Boureghda, Chaima, Debache, Abdelmadjid, Carboni, Bertrand, Khodja, Imène Amine, Boulcina, Raouf, Kermiche, Oumeima   +5 more
core   +1 more source

pKa engineering of a near‐infrared fluorescent probe for sensitive imaging of oxidative stress in atherosclerotic plaques

Smart Molecules, EarlyView.
A pKa‐engineered near‐infrared fluorescent probe (DCM‐2F‐B) enables sensitive imaging of oxidative stress in atherosclerotic plaques. Difluoro substitution lowers the phenolic hydroxyl pKa from 9.1 to 6.0, achieving near‐complete ionization at physiological pH.
Qianqian Yu, Jiahui Liang, Tijian Zhou, Qiaomeng Chen, Xuechun Yan, Zhikang Zheng, Huyou Wang, Jihong Liu, Yi Dong, Wei‐Hong Zhu, Qi Wang   +10 more
wiley   +1 more source

Advances in Unconventional and Sustainable Synthetic Approaches to Benzopyran Scaffolds

The Chemical Record, EarlyView.
This review provides a comprehensive and critical analysis of low‐impact synthetic methodologies reported in the last 8 years (2018–2026) for the construction of benzopyran‐derived scaffolds, such as coumarins, flavones, chromones, chromenes, and chromanes. The benzopyran scaffold is a versatile family of heterocycles found in a wide range of bioactive
Nathalia B. Sá, Patrick C. Nobre, Isabelly O. Ferreira, Juliano B. Azeredo, Vanessa Nascimento   +4 more
wiley   +1 more source

Electrospun Biomass‐Derived Flexible Anodes With Hierarchical Structure via Cobalt MOF Integration for Sodium‐Ion Batteries

ENERGY &ENVIRONMENTAL MATERIALS, Volume 9, Issue 6, November 2026.
Hierarchically porous, N‐doped freestanding anode enables reversible Na+ insertion/desorption and Na–Co alloying, delivering fast kinetics, structural robustness, and durable sodium‐storage performance even under bending/folding. To develop a green, sustainable, and high‐performance anode for sodium‐ion batteries (SIBs), flexible biomass‐based carbon ...
Yuqiong He, Shengping Hou, Jie Liu, Shengbo Ge, Siqun Wang, Mashallah Rezakazemi, Feng Liang, Guanben Du, Kaimeng Xu   +8 more
wiley   +1 more source

Ionic liquid–driven pyran synthesis: Pathways and perspectives

Journal of Ionic Liquids
Pyrans and their fused derivatives are privileged oxygen heterocycles with broad biological activity and industrial relevance, yet their sustainable synthesis remains a continuing challenge.
Pravas Maity, Amrit Krishna Mitra
doaj   +1 more source

Organocatalytic clean synthesis of densely functionalized 4H-pyrans by bifunctional tetraethylammonium 2-(carbamoyl)benzoate using ball milling technique under mild conditions

Green Chemistry Letters and Reviews, 2016
A green and simple method has been developed for efficient preparation of diverse annulated 2-amino-3-cyano-4H-pyran derivatives in the presence of a low loading of tetraethylammonium 2-(carbamoyl)benzoate (TEACB), as a bifunctional organocatalyst, under
Mohammad G. Dekamin, Mohammad Alikhani, Shahrzad Javanshir   +2 more
doaj   +1 more source