7-Methoxycoumarin ester

Bousquet, E. Romeo, G. Giannola, L. I. High-performance liquid chromatography with fluorometric detection in biological tissues of the 4-bromomethyl-7-methoxycoumarin ester... 

For more specific analysis, chromatographic methods have been developed. Using reverse-phase columns and uv detection, hplc methods have been appHed to the analysis of nicotinic acid and nicotinamide in biological fluids such as blood and urine and in foods such as coffee and meat. Derivatization techniques have also been employed to improve sensitivity (55). For example, the reaction of nicotinic amide with DCCI (AT-dicyclohexyl-0-methoxycoumarin-4-yl)methyl isourea to yield the fluorescent coumarin ester has been reported (56). After separation on a reversed-phase column, detection limits of 10 pmol for nicotinic acid have been reported (57). 

CijHijNOj 83073-63-6) see Tilisolol hydrochloride l-methyl-2-[[4-(methoxycarbonyl)phenyl]methyl]-l,2-hy-drazinedicarboxylic acid bis(phenylmethyl) ester (CifiHjgNjOg) see Procarbazine 5-methyl-8-methoxycoumarin... 

The reaction of 2,2-dimethyl-4,6-dioxo-l,3-dioxane (Meldrum s acid 394) and its analogues with 3-dialkylaminophenols has been used to prepare some fluorescent 7-dialkylamino-4-hydroxycoumarins (Scheme 127) (77M499). The substituted malonic acid (395) or its dehydration product is a possible intermediate, since it is known that diaryl-malonic esters are accessible from phenols and the 1,3-dioxane. 3-Methoxyphenol yields the pyrano[3,2-c]benzopyran-2,5-dione (396) in this reaction, presumably by annelation of another ring on to initially formed 4-hydroxy-7-methoxycoumarin. 

No or only minimal cytotoxicity of most coumarins could be detected in normal cells in contrast to the positive control gallic acid. On the other hand, several of them showed concentration-dependent cytotoxicity against tumor cell lines HSC-2 and HSC-3. Among them, 6-hydroxy-7-methoxycoumarin derivatives (C29, C30, C39, C40, C41, C42, and C43) were cytotoxic to tumor cell fine HSC-2. However, C34 and C38 were relatively non-toxic to all cell lines used. It is suggested that the presence of polar substituents such as ester and alcohol group at the C-3 and/or C-4 position was unfavorable for cytotoxicity. This observation confirms the recent findings that 3,4-dimethyl- (C17) and 3,4-cyclopentano-6-hydroxy-7-methoxycoumarin (C22) showed marked cytotoxic effects [25]. However, it should be noted that 4-methyl-6-hydroxy-... 

In some cases, precolumn analyte derivatization is applied in bioanalytical LC-MS. Derivatization of L-368,899 with trifluoroacetic anhydride was performed to eliminate carryover and adsorption effects [8]. Derivatization of 5-fluorouracil with 4-bromomethyl-7-methoxycoumarin [9] and conversion of sampatrilat to its dimethyl ester [10] was performed in order to enhance the ionization efficiency. 

The feasibility of the screening scheme of fluorescent RNP sensors (Fig. 10.4) was demonstrated by utilizing libraries of fluorescent RNP receptors constructed from the 29 different ATP-binding RNP, which obtained from RRE30N RNAs (Fig. 10.2a) and Rev peptides modified with various fluorophores, 7-methoxycoumarin-3-carboxylic acid (7mC-Rev), 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole (NBD-Rev), and Cy5 mono NHS ester (Cy5-Rev) at the N-terminal. Complex formation of the 29 different RNA subunits and Pyr-Rev, 7mC-Rev, NBD-Rev, or Cy5-Rev afforded four independent fluorescent RNP libraries. 

The phenacyl esters are more readily prepared than the other derivatives. The fluorescent tag 4-bromomethyl-7-methoxycoumarin may however offer increased sensitivity. Due to the bulky nature of the fluorescent products, separation factors may be poorer and allow only positive identification of a limited number of fatty acids. 

A wide variety of other esters has been made, or may potentially be accessible, by the type of procedure outlined in this section. To give a couple of examples, the naphthacyl esters were made for improved detectability in HPLC analysis in the same way as the phenacyl esters mentioned earlier [102], the fluorescent esters of 4-methyl-7-methoxycoumarin were made from the 4-bromomethyl-7-methoxycoumarin by the potassium salt procedure [103] and anthrylmethyl esters were obtained by an extractive alkylation procedure [104]. 

Diazomethyl-7-methoxycoumarin is a rather stable reagent which allows convenient derivative formation carboxylic acids form esters by heating in acetonitrile. With alcohols, fluorescent ethers are obtained in dichlo-romethane in the presence of HBF4 as catalyst [477]. 

Hydroxymethylanthracene [493], 2-dansylaminoetha-nol [494] and 4-hydroxymethyl-7-methoxycoumarin (HO-Mmc) [495] have been used for ester formation. 

Bruno, R Caselli, M. Traini, A. HPTLC and OPEC separation and detection of prostaglandin esters using 4-bromomethyl-7-methoxycoumarin (BrMMC). J. Planar Chromatogr.-Mod. TLC1988, 1, 299-303. 

Li, J. Liu, X. Zhao, R. Xiong, S. Ma, H. Lu, Q. Xu, L. Labeling analysis of neuropeptides with 7-methoxycoumarin-3-carboxylic acid N-succinimidyl ester. Gaodeng Xuexiao Huaxue Xuebao 2006,27, 2297-2299. 

Methoxycoumarin-3-carbonyl azide 7-Methoxycoumarin-3-carboxylic acid 7-Methoxycoumarin-3-carboxylic acid succinimidyl ester Pacific Blue (6,8-Diliuoro-7-hydroxycoumarin-3-carboxylic acid)... 

Hydroxy-2-oxo-2//-1 -benzopyran-3-carboxylic acid Me ester, in H-00426 7-Methoxycoumarin-3-carboxylic acid, in H-00426... 

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