Results 31 to 40 of about 2,756 (214)

One-Pot Pyrrolidine-Catalyzed Synthesis of Benzopyrans, Benzothiopyranes, and Dihydroquinolidines

CHIMIA, 2007
A simple catalytic racemic synthesis of benzopyranes, benzothiopyranes and 1,2-dihydroquinolines is presented. The organocatalytic domino reactions between 2-heteroatom substituted aldehyde derivatives and ?,?-unsaturated aldehydes or ...
Ismail Ibrahem, Henrik Sundén, Ramon Rios, Gui-Ling Zhao, Armando Córdova   +4 more
doaj   +1 more source

Nano-SiO2/DBN: an efficacious and reusable catalyst for one-pot synthesis of tetrahydrobenzo[b]pyran derivatives

BMC Chemistry, 2021
Background The nano-sized particles enhance the exposed surface area of the active part of the catalyst, thereby increasing the contact between precursors and catalyst considerably. In this study, nano-SiO2/1,5-diazabicyclo[4.3.0]non-5-en was synthesized,
Maryam Mehravar, Bi Bi Fatemeh Mirjalili, Elaheh Babaei, Abdolhamid Bamoniri   +3 more
doaj   +1 more source

Antimicrobial Benzopyrans from the Receptacle of Sunflower

Bioscience, Biotechnology, and Biochemistry, 1996
The antimicrobial substances in sunflower (Helianthus annuus) were investigated. Two antifungal benzopyran derivatives, 6-acetyl-2,2-dimethyl-1,2-benzopyran (1) and 6-acetyl-7-hydroxy-2,2-dimethyl-1,2-benzopyran (2), were isolated from the ethanol extract of sunflower receptacles.
SATOH, Atsushi, UTAMURA, Hisashi, ISHIZUKA, Masato, ENDO, Natsuyo, TSUJI, Masahisa, NISHIMURA, Hiroyuki   +5 more
openaire   +2 more sources

Comparative Metabolomics Study of Four Kinds of Xihu Longjing Tea Based on Machine Fixing and Manual Fixing Methods

Foods, 2023
China Xihu Longjing tea is famous for its good flavor and quality. However, information on its related metabolites, except for flavonoids, is largely deficient. Different processing methods for China Xihu Longjing tea fixing—by machines at both the first
Hongchun Cui, Yuxiao Mao, Yun Zhao, Haitao Huang, Junfeng Yin, Jizhong Yu, Jianyong Zhang   +6 more
doaj   +1 more source

Enantioselective Decarboxylative Alkylation of β‑Keto Acids to ortho-Quinone Methides as Reactive Intermediates: Asymmetric Synthesis of 2,4-Diaryl-1-benzopyrans

, 2018
A novel and efficient asymmetric synthesis of 2,4-diaryl-1-benzopyrans via enantioselective decarboxylative alkylation of β-keto acids to o-QM intermediates, followed by sequential cyclization and dehydration, has been developed. The synthetically useful
Dae Young Kim (1734676), Hyun Jung Jeong (5159462)   +1 more
core   +1 more source

Iodine-Substituted Dithiocarbamic Flavanones—A Structure–Activity Relationship Study of Their Antioxidant Properties

Molecules
The antioxidant properties of novel diiodo-substituted 3-dithiocarbamic flavanones were investigated. The three frameworks that proved to be the most active ones in our previous studies were selected.
Mihail Lucian Birsa, Laura Gabriela Sarbu   +1 more
doaj   +1 more source

Specific stereochemistry of OP-1074 disrupts estrogen receptor alpha helix 12 and confers pure antiestrogenic activity

Nature Communications, 2018
Estrogen receptor alpha (ERα) plays critical roles in the etiology and treatment of breast cancer. Here the authors synthesize benzopyrans with variable side chains to identify antiestrogenic compounds and characterize OP-1074, a compound that exhibits ...
S. W. Fanning, L. Hodges-Gallagher, D. C. Myles, R. Sun, C. E. Fowler, I. N. Plant, B. D. Green, C. L. Harmon, G. L. Greene, P. J. Kushner   +9 more
doaj   +1 more source

Amberlyst 15 Catalyzed Prenylation of Phenols: One-Step Synthesis of Benzopyrans

Molecules, 1997
A convenient one-step synthesis of 2,2-dimethylchromans and chromenes using Amberlyst 15 as a catalyst is described.
A. Banerji, A. Jain, G. P. Kalena
doaj   +1 more source

Radical cyclisation : synthesis of 4H-furo(3,2-c)-1-benzopyrans

, 1988
3,4-dihydro-3-bromo-4-(prop-2-ynyloxy)-2H-1-benzopyrans (3) undergo radical cyclisation when treated with nBu3SnH and AIBN to give good yield of 2,3,3a,9b-tetrahydro-3-methylene-4H-furo (3,2-c)benzopyrans (4)
Balasubramanian, K. K., K.K Balasubramanian, Ariamala, G., G Ariamala   +3 more
core   +1 more source

A Structure–Activity Relationship Study on the Antioxidant Properties of Dithiocarbamic Flavanones

Antioxidants
The antioxidant properties of 3-dithiocarbamic flavanones have been investigated. The influence of the halogen substituents on ring A of the flavanones and the nature of the secondary amine from the dithiocarbamic moiety have been accounted.
Mihail Lucian Birsa, Laura Gabriela Sarbu   +1 more
doaj   +1 more source