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Organocatalytic Synthesis of Chiral Benzopyrans.
ChemInform, 2006AbstractChemInform 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.
Thavendran Govender +3 more
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Letters in Organic Chemistry, 2005
Sulfamic acid catalyses the one-pot three components coupling of aldehydes, anilines and electron rich dienophiles such as dihydropyran, dihydrofuran and ethyl vinylether resulting in the formation of pyrano, furano and ethoxy benzopyrans.
R. Kumar +3 more
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Sulfamic acid catalyses the one-pot three components coupling of aldehydes, anilines and electron rich dienophiles such as dihydropyran, dihydrofuran and ethyl vinylether resulting in the formation of pyrano, furano and ethoxy benzopyrans.
R. Kumar +3 more
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Journal of the Chemical Society, Chemical Communications, 1983
Trapping and low temperature matrix isolation experiments show that 2-benzopyran-3-one (1) is efficiently generated by thermolysis or photolysis of the bis-lactone (2); flash vacuum thermolysis of (2) yields isocoumarin (5) and photolysis of (2) in an argon matrix gives (1) and the ketene (6).
David A. Bleasdale +3 more
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Trapping and low temperature matrix isolation experiments show that 2-benzopyran-3-one (1) is efficiently generated by thermolysis or photolysis of the bis-lactone (2); flash vacuum thermolysis of (2) yields isocoumarin (5) and photolysis of (2) in an argon matrix gives (1) and the ketene (6).
David A. Bleasdale +3 more
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Benzopyrans. Part 44. Synthesis of 3‐(4‐Oxo‐4H‐1‐benzopyran‐2‐yl)indolizines.
ChemInform, 2003AbstractFor Abstract see ChemInform Abstract in Full Text.
Chandra Kanta Ghosh +2 more
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Journal of the Chemical Society, Perkin Transactions 1, 1988
The enamine (2), prepared from the title benzopyranone (1; R2= H, Me, and Ph) and dimethylformamide dimethyl acetal, on treatment with ammonia and hydroxylamine gives the fused pyridine (5) and pyridine 2-oxide (10), respectively. Hydrazine, phenylhydrazine, and guanidine undergo initial 1,6-addition to the enamine (2) ultimately giving the pyrazoles ...
Chandra Kanta Ghosh +3 more
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The enamine (2), prepared from the title benzopyranone (1; R2= H, Me, and Ph) and dimethylformamide dimethyl acetal, on treatment with ammonia and hydroxylamine gives the fused pyridine (5) and pyridine 2-oxide (10), respectively. Hydrazine, phenylhydrazine, and guanidine undergo initial 1,6-addition to the enamine (2) ultimately giving the pyrazoles ...
Chandra Kanta Ghosh +3 more
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Benzopyrans from Melicope ptelefolia leaves
Phytochemistry, 1997Abstract Investigation of leaves of Melicope ptelefolia afforded 18 2,2-dimethyl-2H-1-benzopyrans, consisting of 14 new members, including one benzodipyran and four known compounds. Their structures were established by mass and NMR spectroscopy, especially NOE and HMBC experiments. © 1997 Elsevier Science Ltd.
Christine Kamperdick +3 more
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Benzopyran sulfonamides as KV1.5 potassium channel blockers
Bioorganic & Medicinal Chemistry Letters, 2007K(V)1.5 blockers have the potential to be atrium-selective agents for treatment of atrial fibrillation. The benzopyrans provide a template for the synthesis of potent and selective K(V)1.5 blockers.
John, Lloyd +11 more
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Benzopyran dimers from melicope ptelefolia
Phytochemistry, 1998Abstract The leaves of Melicopte ptelefolia afforded two new 2,2–dimethyl–2H–1–benzopyran dimers named 5,5’–dimethoxy–alloagerasanin and melifolin. Their structures were established by NMR spectroscopy, especially NOE and HMBC. © 1998 Published by Elsevier Science Ltd. All rights reserved.
Nguyen Hong Van +3 more
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Benzopyran derivatives from Werneria nubigena
Phytochemistry, 1997Abstract The investigation of Werneria nubigena afforded the rare 2,2-dimethyl-6-acetyl-8-(3′-hydroxy-3′-methyl- trans -but- 1′-enyl)-chrom-3-ene and new 2,2-dimethyl-6-acetyl-8-(3′-hydroxy- 3′-methyl- trans -but-1′-enyl)-chroman-4-one ( 1 ). Thechemotaxonomic relevance is discussed briefly.
PIACENTE, Sonia +4 more
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A benzopyran derivative substituted at position 3
Acta Crystallographica Section C Crystal Structure Communications, 2002In (E)-3-[[(diphenoxyphosphoryl)methylhydrazono]methyl]-4H-1-benzopyran-4-one, C(23)H(19)N(2)O(5)P, the benzopyran-methylhydrazone moiety is planar and the two phenoxy phenyl rings are inclined at angles of 21.29 (6) and 89.33 (5) degrees. Weak C[bond]H...O and C[bond]H...N intramolecular interactions exert some influence on the planarity and ...
Agnieszka J, Rybarczyk-Pirek +3 more
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