Methyl Esculetin

Methylene Iodide, 1, 57 7, 90 0-Methyl Esculetin, 4, 45 df-METHYL Ethyl Acetic Acid, 5,75 Methyl formate, 3, 67 a-M ETHYL d-GLUCOSIDE, 6, 64... 

Compounds 1 = 4-hydroxycoumarin 2 = umbelliferon 3 = 4-methyl-esculetin 4 = isopimpinellin 5 = esculin 6 = flavone 7 = a-naphtoflavone 8 = kaempferol 9 = quercetin 10 = isoquercitrin 11 = robinetin 12 = robinin 13 = myricetin 14 = luteolin 7-O-glucoside 15 = rutin 16 = hes-peretin 17 = hespiridin 18 = naringin 19 = pelargonin chloride 20 = polargonin chloride 21 = malvin chloride. 

A pure product may be obtained by dissolving with the aid of heat and stirring ioo g. of /3-methyl esculetin in a solution of 200 g. of borax in 700 cc. of water. The solution obtained is filtered while hot and then cooled, whereupon the esculetin borate separates (Note 3). This is filtered off and dissolved in 1800 cc. of water, and the solution thus obtained added to 50 g. of concentrated sulfuric acid in 500 cc. of water. /3-Methyl esculetin separates and, after the mixture has been cooled, is filtered, washed, and dried. From 100 g. of the crude material, 85 g. of pure product melting at 272-2740 (uncor.) is obtained. This is generally nearly colorless but occasionally possesses a slight grayish tinge. 

Methylene iodide, I, 57-59 /3-Methyl esculetin, IV, 45-46 (//-Methyl ethyl acetic acid, V, 75-77 Methyl formate, III, 67 Methyl hexyl carbinol, I, 61-66 Methyl iodide, I, 57, 59 5-Methyl isatin, V, 74 Methyl o-nitrobenzoate, III, 72 Methyl m-nitrobenzoate, III, 71-72, 73-Methyl oxalate, V, 60 Methyl Red, II, 47-51... 

Kim, B.G., Lee, Y., Hur, H.G., Lim, Y., Ahn, J.H. (2006b) Production of three O-methylated esculetins with Escherichia coli expressing O-methyltransferases from poplar. Biosci., Biotechnol. Biochem., 70,1269-72. 

Other Names Coumarin, 6,7-dihydroxy-4-methyl- Esculetin, 4-methyl- 4-Methyl-6,7-dihydroxy-coumarin 4-Methylaesculetin 4-Methylesculetin 4-Methylesculetol 6,7-Dihydroxy-4-methyl-coumarin Methylesculetin NSC 11828 NSC 688807 CA Index Name 2H-l-Benzopyran-2-one, 6,7-dihydroxy-4-methyl-CAS Registry Number 529-84-0 Merck Index Number Not listed Chemical Structur... 

NMR, 4, 575 Erythritol, 1,4-anhydro-structure, 4, 546 Erythromycin antibacterial veterinary use, 1, 206 as pharmaceutical, 1, 153 synthesis, 1, 480 Erythropterin biosynthesis, 3, 321 occurence, 3, 323 structure, 3, 276 synthesis, 3, 289 Erythropterin, 3,5-dimethyl-methyl ester synthesis, 3, 303 Erythrosine application, 3, 879 Esculetin... 

Sharma and Seshadri of the oxidative dimerization of both esculetin and isoscopoletin (7-methylesculetin) upon treatment with [Fe(DMF)3Cl2] [FeC ] strongly suggests the participation of 65 and its 7-methylated analog, or their protonated forms. The coupling positions are consistent with the positions of high spin population indicated in 65. 

Isoscopoletin (7), a 7- methyl derivative of esculetin is less inhibitory than esculetin itself, while scoparone (6), a 6,7-dimethyl derivative of esculetin, is completely inactive. The 7-O-methylesculin (11) and 6,7,8-trimethoxycoumarin (12) are totally deprived of activity. Evidently, a methylation of the phenolic OH decreases the activity. 

Two of the ten hydroxycoumarin derivatives tested showed activity against NDV, namely esculetin (2) and its diacetate (2a), when applied in cylinders at a dose of 2.8 and 1.9 mM/0.1 ml, respectively. Their activity was significant, although inferior when compared to that of ribavarin (used as a reference paramyxovirus inhibitor) at a dose of 2.0 mM /0.1 ml. The remaining compounds tested were without effect on the replication of the four viruses studied. Evidently, no definitive conclusion could be drawn regarding structure-activity correlations. It could be noticed, however, that methylation and glucosidation of esculetin (2) lead to a loss of activity. 

Phenylketonuria can be induced experimentally using various phenylalanine derivatives. Among these are phenylalanine alkylating agents [236] and several o-dihydroxy derivatives [237-239] particularly esculetin (6,7-dihydroxy-coumarin) derivatives were found to be very potent in inhibiting phenylalanine hydroxylase both in vivo and in vitro [240, 241]. This observation led to further structure-activity studies applying different 3- and 4-substituted 6,7-dihydroxy-coumarins. In vitro 4-methyl-, 4-butyl- and 4-pheny -6,7-dihydroxycoumarin, and in vivo esculin, 4-methyl- and 4-phenyl-6,7-dihydroxycoumarin appear to be the most powerful inhibitors of the rat liver enzyme (Table 3,7). 

Esculetin, umbeUiferone (7-hydroxycoumarin) and 7-hydroxy-4-methyl coumarin are strong xanthine oxidase inhibitors (Chang and Chiang 1995). The structure of 7-hydroxy coumarin plays a very important role in xanthine oxidase inhibition, the 6-hydroxy group present in the molecule of 7-hydroxy coumarin, e.g. esculetin enhanced the activity, whereas substitution by the 6-methoxy group, e.g. scopoletin (formula [47]), reduced the inhibitory effect. (Chang and Chiang 1995). 

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