Results 171 to 180 of about 10,732 (222)

Chromene as Antioxidants

2023
Chromene is a heterocyclic compound that contains oxygen in its ring. It is widely obtained naturally from both animals and plants, and it is an integral part of alkaloids, tocopherol, anthocyanins, and flavonoids. The 2-oxo-2H-chromene is called coumarins, and coumarins have excellent antioxidant potential due to the presence of the phenol group, more
Rajeshwar Kamal Kant Arya, Arun Kumar, Anchala Guglani, Dheeraj Bisht, Deepak Kumar   +4 more
openaire   +1 more source

Photochromism of chromene crystals; a new property of old chromenes

Chemical Communications, 2000
Of the four chromene compounds; 3,3-diphenyl-5,10a-dihydro-3H-benzo[f]chromene (CHR1), 6-methoxy-2,2-diphenyl-2H-benzo[h]chromene (CHR2), 2,2-diphenyl-2H-benzo[h]chromene (CHR3) and 6,7-dimethoxy-2,2- diphenyl-2H-chromene (CHR4), CHR2–4 exhibited crystalline state photochromism.
Jonathan Hobley, Masahiro Goto, Maki Kishimoto, Vincenzo Malatesta, William Giroldini, Lucia Wis, Roberto Millini, H. Fukumura   +7 more
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ChemInform Abstract: Natural and Synthetic Chromenes, Fused Chromenes, and Versatility of Dihydrobenzo[h]chromenes in Organic Synthesis

ChemInform, 2014
AbstractReview: 438 refs.
Ramendra Pratap, Vishnu Ji Ram
openaire   +1 more source

Syntheses on the basis of 2H-chromen-2-one and 2H-chromene-2-thione

Russian Journal of Organic Chemistry, 2006
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A. A. Avetisyan, A. G. Alvandzhyan
openaire   +1 more source

Unusual chromenes from Peperomia blanda

Phytochemistry, 2006
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Leosvaldo S M, Velozo, Marcelo J P, Ferreira, Maria Isabel S, Santos, Davyson L, Moreira, Vicente P, Emerenciano, Maria Auxiliadora C, Kaplan   +5 more
openaire   +2 more sources

Chromenes and Chromanones. Part I The Birch Reduction of Coumarins and 2H-Chromenes

HETEROCYCLES, 1994
The reduction of coumarin, 4-methylcoumarin, 2,2-dimethyl- 2H-chromene and 2,2,4-trimethyl-2H-chromene with sodium or lithium in liquid ammonia with the presence or without donor of protons was carried out. The formation of phenolic products was observed when a limited amount of alcohol as a proton donor was present in the reaction medium.
Czeslaw Wawrzenczyk, Miroslaw Aniol, Przemyslaw Lusiak   +2 more
openaire   +1 more source

Bioactive chromenes fromRhyncholacis penicillata

Phytochemistry, 1994
Investigation of the aerial parts of Rhyncholacis penicillata afforded the new chromenes, 7-hydroxy-6-(3-methylbutyryl)-5-oxymethyl-chromene (rhynchonin A) and 7-hydroxy-6-(2-methylbutyryl)-6-oxymethylchromene (rhynchonin B). Structures were elucidated by spectroscopic methods and independent synthesis.
G, Burkhardt, H, Becker, M, Grubert, J, Thomas, T, Eicher   +4 more
openaire   +2 more sources

Dimeric chromenes and mixed dimers of a chromene with euparin from Encelia canescens

Phytochemistry, 1983
Abstract The investigation of Encelia canescens afforded, in addition to several known compounds, four new dimeric p -hydroxyacetophenone derivatives, two epimeric chromene dimers and two epimeric mixed dimers of euparin and encecalin. Furthermore, derivatives of tremetone and of encecalin were present. The structures were elucidated hy high field
Ferdinand Bohlmann, Elena Tsankova, Jasmin Jakupovic, Robert M. King, Harold Robinson   +4 more
openaire   +1 more source

Pharmacokinetic Aspects of Chromenes

2023
Unfavourable pharmacokinetics is the major hurdle for the new chemical entity (NCE) to become a drug during the drug discovery and development process. Early evaluation of absorption, distribution, metabolism, and excretion (ADME) characteristics for the promising candidates not only speed up the drug development stages but also lower the attrition ...
Abhishek Gour, Ashish Dogra, Utpal Nandi
openaire   +1 more source

Novel photoreactions of chromene derivatives. The photolysis of 4-acetoxy-2-chromene.

Tetrahedron, 1987
Abstract The photolysis of 4-acetoxy-2 H -chromene 1a leads to a mixture of o -acetoxyphenyl vinyl ketone 2a , 4-chromanone 3, chromone 4 , 3-acetoxy-4-chromanone 5, 3-hydroxy-4-chromanone 6 and a cyclobutane dimer with anti head-to-head structure (7).
Maria J. Climent, Hermenegildo Garcia, Miguel A. Miranda, J. Primoa   +3 more
openaire   +1 more source