Results 81 to 90 of about 10,026 (250)

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

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

Pueraria mirifica: a critical review of the ethnobotany, phytochemistry, pharmacology and challenges in standardization and safety

Frontiers in Pharmacology
BackgroundPueraria candollei var. mirifica (Airy Shaw and Suvat.) Niyomdham (Pueraria mirifica), locally known as “White Kwao Krua” or “white kudzu”, is a renowned medicinal botanical drug indigenous to Southeast Asia, particularly Thailand and Myanmar ...
Haiqin Zeng, Haiqin Zeng, Haiqin Zeng, Juan Wen, Juan Wen, Juan Wen, Juan Wen, Minqi Chen, Minqi Chen, Minqi Chen, Zhendong Qiu, Zhendong Qiu, Zhendong Qiu, Shiping Huang, Erwei Hao, Erwei Hao, Erwei Hao, Zhengcai Du, Zhengcai Du, Zhengcai Du, Chun Yao, Chun Yao, Chun Yao, Xiaotao Hou, Xiaotao Hou, Xiaotao Hou, Xiaotao Hou, Jiagang Deng, Jiagang Deng, Jiagang Deng   +29 more
doaj   +1 more source

Synthesis and anticonvulsant and sedative-hypnotic activity of 4-(alkylimino)-2,3-dihydro-4H-1-benzopyrans and benzothiopyrans

, 1990
A series of 4-(alkylimino)-5-hydroxy-7-alkyl-2,3-dihydro-4H-1-benzopyrans and -thiopyrans were synthesized and evaluated for anticonvulsant activity. Preliminary screening of these compounds revealed that 2,2-dimethyl-4-[(2-hydroxyalkyl)imino]-5-hydroxy ...
A. Bonsignori, P. Melloni, L. Merlini, M. Valsecchi, M. L. Quadri, A. Arnoldi, A. C. Rossi   +6 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

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

Antitumor activity of three benzopyrans isolated from Hypericum polyanthemun

, 2005
In the present study we have investigated the in vitro antitumor effects of three benzopyrans, 6-isobutyryl-5,7-dimethoxy-2,2-dimethylbenzopyran (1), 7-hydroxy-6-isobutyryl-5-methoxy-2,2-dimethylbenzopyran (2) and 5-hydroxy-6-isobutyryl-7-methoxy-2,2 ...
Schwartsmann, Gilberto, Henriques, Amelia Teresinha, Rocha, Adriana Brondani da, Faria, Denise Heidrich, Poser, Gilsane Lino von, Grivicich, Ivana, Kayser, Guilherme B., Ferraz, Alexandre de Barros Falcão   +7 more
core   +1 more source

Preventing the Formation of the Long-Lived Colored Transoid-Trans Photoisomer in Photochromic Benzopyrans

, 2016
A new photochromic fused benzopyran presenting a bridge between the pyran double bond and the benzenic ring was prepared. While the UV irradiation of usual benzopyrans leads to the formation of two colored photoisomers with very different thermal ...
Stéphanie Delbaere (1744363), Céu M. Sousa (2178632), Paulo J. Coelho (1456876), João Seixas de Melo (2178630), Jérôme Berthet (2053732), João Pina (1363344)   +5 more
core   +1 more source