Results 51 to 60 of about 2,222 (186)

Copper-catalysed asymmetric allylic alkylation of alkylzirconocenes to racemic 3,6-dihydro-2H-pyrans

Beilstein Journal of Organic Chemistry, 2015
Asymmetric allylic alkylation is a powerful reaction that allows the enantioselective formation of C–C bonds. Here we describe the asymmetric alkylation of alkylzirconium species to racemic 3,6-dihydro-2H-pyrans.
Emeline Rideau, Stephen P. Fletcher
doaj   +1 more source

Enzymology of Pyran Ring A Formation in Salinomycin Biosynthesis [PDF]

Angewandte Chemie, 2015
AbstractTetrahydropyran rings are a common feature of complex polyketide natural products, but much remains to be learned about the enzymology of their formation. The enzyme SalBIII from the salinomycin biosynthetic pathway resembles other polyether epoxide hydrolases/cyclases of the MonB family, but SalBIII plays no role in the conventional cascade of
Luhavaya, Hanna, Dias, Marcio VB, Williams, Simon R, Hong, Hui, de Oliveira, Luciana G, Leadlay, Peter F   +5 more
openaire   +7 more sources

Photochromic carbazole photoinitiators for precision visible‐light photopolymerization

Polymer International, EarlyView.
New carbazole–naphthopyran derivatives were employed as visible‐light‐activated photoinitiators, enabling rapid and localized radical photopolymerization to produce well‐defined thin solid objects within minutes. Abstract Two carbazole derivatives, each incorporating a naphthopyran unit and an aromatic ketone, were synthesized and evaluated as ...
Mauro Magalhães, Céu M Sousa, José R Fernandes, Paulo J Coelho   +3 more
wiley   +1 more source

Stimulation of Antibody Formation by Pyran Copolymer

Experimental Biology and Medicine, 1970
SummaryPyran copolymer, administered with sheep red blood cells to mice, enhances the early rate of appearance of antibody-forming spleen cells. Although the cytotoxicity and pyrogenicity of pyran and bacterial endotoxins are similar, pyran, in contrast to endotoxin, does not trigger a nonspecific initiation of antibody formation; it only enhances ...
W, Braun, W, Regelson, Y, Yajima, M, Ishizuka   +3 more
openaire   +2 more sources

The continuing significance of chiral agrochemicals

Pest Management Science, Volume 81, Issue 4, Page 1697-1716, April 2025.
In the time frame 2018–2023, around 43% of the 35 chiral agrochemicals introduced to the market (herbicides, fungicides, insecticides, acaricides, and nematicides) contain one or more stereogenic centers in the molecule, and almost 69% of them have been marketed as racemic mixtures of enantiomers or stereoisomers.
Peter Jeschke
wiley   +1 more source

Structure‐Controlled Cyclopentadithiophene Derived Non‐Fullerene Acceptors for Efficient Near‐Infrared Organic Photodetectors

Small, EarlyView.
This work demonstrates high‐performance solution‐processed NIR OPDs using DTP‐ and DTTP‐based NFAs (OC and SC), where donor‐core engineering enables tunable absorption and balanced optoelectronic properties; notably, DTP‐based devices achieve broad NIR response, low dark current, and high detectivity, highlighting their potential for advanced NIR ...
Jong‐Woon Ha, Jae‐Hyun Kim, Byoungwook Park, Honghyun Park, Sung Cheol Yoon, Jaebin Jeong, Seunghun Lee, Jaeil Park, Jun‐Gyu Choi, Seo‐Jin Ko, Seung‐Hoon Lee, Sungjun Park   +11 more
wiley   +1 more source

An Efficient, Simple and Green Zn(Phen)2Cl2 Complex Catalyzed Synthesis of 4-H-Benzo[b]pyrans in Water at Ambient Temperature

E-Journal of Chemistry, 2011
An efficient method for the synthesis of 4-H-benzo[b]pyrans has been developed by the use of Zn(Phen)2Cl2(2 mol%) as an ecofriendly catalyst. The mixture of an appropriate aldehyde, malononitrile and dimedone in the presence of the Zn(Phen)2Cl2 as an ...
E. Mosaddegh, A. Hassankhani, G. Mansouri   +2 more
doaj   +1 more source

Energy Transfer in Nanodroplet‐Based Luminescent Solar Concentrators

Small, EarlyView.
We present novel luminescent solar concentrators (LSCs) featuring polymer composites with fluorescent dye‐doped oil nanodroplets. This liquid environment ensures high dye solubility and preserves fluorescence quantum yields, even at high local dye concentrations.
Lorenzo Vallan, Julia W. Mikurenda, Alex Parra Sánchez‐Camacho, Maria Lili, Sebastian J. M. Robben, Stefan C. J. Meskers, Michael G. Debije, Claudio Roscini   +7 more
wiley   +1 more source

Potassium phthalimide promoted green multicomponent tandem synthesis of 2-amino-4H-chromenes and 6-amino-4H-pyran-3-carboxylates

Journal of Saudi Chemical Society, 2014
A one-pot efficient, green, practical, and environmentally friendly multicomponent synthesis of 5-oxo-4-aryl-5,6,7,8-tetrahydro-4H-chromenes, ethyl-6-amino-4-aryl-5-cyano-2-methyl-4H-pyran-3-carboxylates as well as 2-amino-4-aryl-7-hydroxy-4H-chromene-3 ...
Hamzeh Kiyani, Fatemeh Ghorbani
doaj   +1 more source

Crystal Structures and Magnetic Properties of Coordination Polymer Complexes of Metal Ions With Kojic Acid Ligands

Zeitschrift für anorganische und allgemeine Chemie, EarlyView.
One‐dimensional coordination polymers of Cu(II) and Co(II) with kojic acid show distinct chain connectivities revealed by X ray crystallography and exhibit extremely weak magnetic interactions, as supported by magnetic measurements and molecular orbital calculations. The crystal structures and magnetic properties of coordination complexes [Cu(C6H5O4)2]
Wataru Fujita, Tomoko Yamaguchi
wiley   +1 more source