7-Ethoxy-4- coumarin

On the other hand, the metabolism of benzo[a]pyrene, ethoxy-coumarin and ethoxyresorufin, which are preferentially oxidized by rodent cytochrome P -450, was greatly induced by the polyhalogenated biphenyls and 3-naphthoflavone. Despite large changes in... 

A. Steensma, J. A. Beamand, D. G. Walters, R. J. Price, B. G. Lake, Metabolism of Coumarin and 7-Ethoxy coumarin by Rat, Mouse, Guinea Pig, Cynomolgus Monkey and Human Precision-Cut Liver Slices , Xenobiotica 1994, 24, 893-907. 

Many of the enzyme/microorganism mediated dealkylation procedures that have been reported have come from the work of Rosazza and his coworkers as a consequence of their studies on Microbial models on Mammalian metabolism. These studies have largely concerned with demethylation of various alkaloids with bacteria and fungi. 0-deethylation reactions with Streptomyces griseus as with dealkylation of 7-ethoxy coumarin gave very poor yields and therefore was not considered a viable synthetic procedure. The quinone imine(I), has been prepared in 64%isolated yield by horseradish peroxidase/hydrogen peroxide O-demethylation of 9-methoxy-ellipticine(II). Studies with H2 0 as a reaction medium demonstrated that the reaction was not a simple demethylation but rather a replacement of the methoxy group by OH from the solvent (as shown in Fig.l)... 

CPH-treatment of rats (1200 mg/kg/d for 2 d) induced the enzymatic activities of other renal cortical drug-metabolizing enzymes such as 7-ethoxy-coumarine-O-deethylase and cytosolic GSH-S-transferase whereas the enzymatic activities of aniline hydroxylase and aminopyrine-N-demethylase were simultaneously decreased or remained unchanged, respectively (Table 1) [74]. Treatment of male and female rats with cephaloridine (750 mg/kg/d) for two weeks to three months resulted in a 2-fold increase of glu-tathione-S-transferase activity in the renal cortex [76]. These results suggest an adaptive response to cephaloridine subchronic treatment. 

Inoue, R., H. Yamazaki, and T. Shimada (2000). Characterization of liver microsomal 7-ethoxy-coumarin 0-deethylation and chlorzoxazone 6-hydroxylation activities in Japanese and Caucasian subjects genotyped for CYP2E1 gene. Arch. Toxicol. 74, 372-378. 

Back DJ, Stevenscn P, Tjia JF. C nparative effects of two antimycotic agents, ketoconazole and terbinafine, on the metabolic of tolbutamide, ethinyloestradiol, cyclospcrin and ethoxy-coumarin by human liver microsomes in vitro. BrJ Clin Pharmacol (1989) 28,166-70. 

Miwa GT, Walsh JS, Lu AYH (1984) Kinetic isotope effects on cytochrome P-450-catalyzed oxidation reactions. The oxidative O-dealkylation of 7-ethoxy-coumarin. J Biol Chem 259 3000-3004... 

Yamazaki H, Nakano M, Gillam EM, Bell LC, Guengerich FP, Shimada T (1996) Requirements for cytochrome b5 in the oxidation of 7-ethoxy-coumarin, chlorzoxazone, aniline, and N-ni-trosodimethylamine by recombinant cytochrome P450 2E1 and by human liver microsomes. Biochem Pharmacol 52 301-309... 

Cyano-7-ethoxy coumarin (7-Ethoxy coumarin-3 -carbonitrile) 139... 

Abbreviations CEC 3-cyano-7-ethoxycoumarin EEC 7-ethoxy-4-trifluoro-methyl-coumarin DBE Dibenzylfluorescein 7-MEC 7-methoxy-4-trifluoro-methyl-coumarin AMMC 3-[2-(N,N-diethyl-N-methylamino)ethyl]-7-methoxy-4-methyl-coumarin 7-BQ 7-Benzyloxoquinone. 

B6 Cyclophosphamide, ifosphamide, nicotine 6 Aminochrysene, aflatoxin, NNK3 [ 7-ethoxy -4-trifluoro-methyl coumarin]... 

Coumarins are readily accessed via the Pechmann condensation of phenols and 1,3-dicarbonyl compounds, which proceeds via electrophilic aromatic substitution of the phenol followed by dehydration and lactonization <1984CHEC, 1996CHEC-II>. In this manner, the amino acid bearing coumarins 676 are formed by a Pechmann condensation of phenols and 2-amino-6-ethoxy-4,6-dioxohexanoic acid 677 (Scheme 161) <2004AGE3432>. The popularity of this approach results from the wide range of readily available substrates (phenols and 1,3-dicarbonyl compounds). However, a major drawback is that electron withdrawing groups on the phenolic component dramatically reduces the yield of a Pechmann reaction. 

An interesting application of the lithiation route for coumarin synthesis is the Michael addition of the aromatic lithio compound to ethoxy methylene malonic ester. 3-Carboxy coumarins are directly obtained by this method. The linear benzocoumarin is also accessible by this method... 

The compounds chosen for the transformation studies, namely 7-methoxy 4-methyl coumarin(III), 7-ethoxy 4-methyl coumarin(IV), 7-butoxy 4-methyl coumarin(V), 7-o-benzyloxy 4-methyl coumarin(VI) and 7-acetoxy 4-methyl coumarin(VII) (Fig. 2), were synthesized following classical chemical methods. Their purity was tested using TLC and their identity was confirmed by comparing their melting points and UV data, as shown in Table I, with literature cited values. 

M.J. Ashwood-Smith, and J. DiGiovanni (1993). Inhibition and inactivation of murine hepatic ethoxy- and pentoxyresorufin O-dealkylase by naturally occurring coumarins. Chem. Res. Toxicol. 6, 872-879. 

Coumarin 4-Methyl- 7-Ethoxy- 6-Methyl 3,4- 2-Thio 6-Amino- 6-Chloro-... 

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