- SIMPLE COUMARINS FROM TWO POPULATIONS OF DIOSMA ACMAEOPHYLLA
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Investigation of two collections of Diosma acmaeophylla afforded seven simple coumarins, three of which were common to both samples.The chemotaxonomic significance of the isolated coumarins is discussed. - Key Word Index: Diosma acmaeophylla; Rutaceae; 7-, 6,7- and 7,8-oxygenated coumarins; chemical systematics.
- Campbell, William E.,Provan, Gordon J.,Waterman, Peter G.
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- Electronic Finetuning of 8-Methoxy Psoralens by Palladium-Catalyzed Coupling: Acidochromicity and Solvatochromicity
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Differently 5-substituted 8-methoxypsoralens can be synthesized by an efficient synthetic route with various cross-coupling methodologies, such as Suzuki, Sonogashira and Heck reaction. Compared to previously synthesized psoralens, thereby promising daylight absorbing compounds as potentially active agents against certain skin diseases can be readily accessed. Extensive investigations of all synthesized psoralen derivatives reveal fluorescence in the solid state as well as several distinctly emissive derivatives in solution. Donor-substituted psoralens exhibit remarkable photophysical properties, such as high fluorescence quantum yields and pronounced emission solvatochromicity and acidochromicity, which were scrutinized by Lippert–Mataga and Stern–Volmer plots. The results indicate that the compounds exceed the limit of visible light, a significant factor for potential applications as an active agent. In addition, (TD)DFT calculations were performed to elucidate the underlying electronic structure and to assign experimentally obtained data.
- Geenen, Sarah R.,Presser, Lysander,H?lzel, Torsten,Ganter, Christian,Müller, Thomas J. J.
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supporting information
p. 8064 - 8075
(2020/06/02)
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- Chemically selective mono-methylation method of coumarin catechol compounds
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The invention provides a chemically selective mono-methylation method of coumarin catechol compounds, and belongs to the field of natural drug synthesis. According to the method, catechol coumarin compounds are added into an organic reaction system in the presence of a proper amount of alkali catalyst, and high selectivity methylation reactions happen between the catechol coumarin compounds and a methylation reagent so as to obtain a mono-methylation product; wherein the mole ratio of the alkali to the catechol coumarin compounds is 1.0-5.0:1; the mole ratio of the methylation reagent to the catechol coumarin compounds is 1.0-2.0:1, the temperature of the reaction system is -20 to 10 DEG C, and the reaction time is 0.5 to 3 hours. The method has the characteristics of simple operation, mild conditions, good selectivity, and high yield, and can be used to prepare mono-methylation products of coumarin catechol compounds with different substituents.
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Paragraph 0038; 0039; 0040; 0041
(2017/05/06)
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- METHODS FOR SYNTHESIS OF PSORALEN DERIVATIVES
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Methods for the synthesis of psoralen derivatives are provided. In one embodiment, the method may include acetylating a compound of formula (II) to form a compound of formula (III), subjecting the compound of formula (III) to a Fries rearrangement to form a compound of formula (IV), and subjecting the compound of formula (IV) to cyclization, reduction and aromatization, to form a compound having the following formula (I):
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- Revision of the structure of a new coumarin isolated from Artemisia carviforia wall
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Four coumarins (1-4) were synthesized by the routes shown in Schemes 2-5, respectively. The previously proposed structure for a new coumarin isolated from Artemisia carviforia was incorrect; the structure of the coumarin is represented by formula (3).
- Harayama, Takashi,Katsuno, Keiko,Nishita, Yoshitaka,Fujii, Masako,Abe, Hitoshi,Takeuchi, Yasuo
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p. 319 - 328
(2007/10/03)
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- Revision of structure of a new coumarin isolated from Artemisia carviforia wall
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Four coumarins (1-4) were synthesized by routes shown in Charts 2-5, respectively. A proposed structure for a new coumarin isolated from Artemisia carviforia was incorrect, and the structure of coumarin should be represented by formula (3).
- Harayama,Katsuno,Nishita,Fujii
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p. 1550 - 1552
(2007/10/02)
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- Synthesis of Apigravin
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Apigravin (V), a new prenylated coumarin, isolated from the seeds of Apium graveolens, has been synthesised starting from 7,8-dihydroxycoumarin (I).The coumarin (I) on partial benzylation followed by methylation and catalytic debenzylation gives 7-hydroxy-8-methoxycoumarin (IV), which on prenylation yields the title compound (V), identical with a natural sample of apigravin.
- Raizada, M. B.,Garg, S. K.,Gupta, S. R.
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p. 918 - 919
(2007/10/02)
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- The Chemical Components of Artemisia apiacea HANCE. II. More Coumarins from the Flower Heads
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A new coumarin, 7-isopentenyloxy-8-methoxycoumarin, was isolated together with 7-hydroxy-8-methoxycoumarin and daphnetin from the flower heads of Artemisia apiacea HANCE. Keywords: Artemisia apiacea HANCE; Compositae; coumarins; daphnetin; 7-hydroxy-8-methoxycoumarin; 7-isopentenyloxy-8-methoxycoumarin
- Shimomura, Hiroko,Sashida, Yutaka,Ohshima, Yukio
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p. 347 - 348
(2007/10/02)
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