2-Methoxy-4-hydroxy-6- -benzoic

When substituents can also be involved in the resonance effects, changes in acidity become more marked. Consider hydroxy- and methoxy-benzoic acid derivatives. The pATa values are found to be 3.0, 4.1, and 4.6 for the ortho, meta, and para hydroxy derivatives respectively, and 4.1, 4.1, and 4.5 respectively for the corresponding methoxy derivatives. 

Saravanan, N., Rajasankar, S. and Nalini, N. (2007) Antioxidant effect of 2-hydroxy-4-methoxy benzoic acid on ethanol-induced hepatotoxicity in rats. Journal of... 

Hydroxy-3,5-dimethoxy-benzeneacetic acid, methyl ester (methyl homosyringate) 4-Hydroxy-3,5-dimethoxy-benzoic acid (syringic acid) 4-Hydroxy-3,5-dimethoxy-benzoic acid ethyl ester (ethyl syringate) 4-Hydroxy-3,5-dimethoxy-benzoic acid methyl ester (methyl syringate) 4-Hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde) 4-Hydroxy-3-methoxy-benzeneacetic acid methyl ester (methyl homovanillate) 4-Hydroxy-3-methoxy-benzoic acid (vanillic acid)... 

Hydroxy-3-methoxy-benzoic acid ethyl ester (ethyl vanillate) 4-Hydroxy-3-methoxy-benzoic acid ethyl ether (vanillyl ethyl ether) 4-Hydroxy-3-methoxy-benzoic acid methyl ester (methyl vanillate) 4-Hydroxy-3-methoxy-benzoic acid methyl ether (vanillyl methyl ether) 4-Methyl-2-(2 -methyl-l-propenyl)-phenol 4-Methyl-2,6-dimethoxyphenol (methylsyringol)... 

Table 11.1 Overview of studies for profiling human pathogens with MALDI-TOF MS at the strain level Examples of strain categorization (A), strain differentiation (B), and strain identification (C). MRSA methicillin-resistant Staphylococcus aureus, MSSA methicillin-sensitive S. aureus, L library-based approach, P proteomics-based approach, CHCA a-cyano-4-hydroxycinnamic acid, CMBT 5-chloro-2-mercaptobenzothiazole, DHB 2-hydroxy-5-methoxy benzoic acid, FA ferulic acid, HABA 2,4-hydroxyphenylazobenzoic acid, SA 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid), THAP 2,4,6-trihydroxyacetophenon. Adapted and modified from Sandrin et al. (2013)... 

Rhizonic acid, 4-0-Metbyl-p-orcinolcarboxylic acid, 2-Hydroxy,3,6-dimethyl-4-methoxy-benzoic acid (Rbizoninsaure, 4-0-Metbyl-P-orcinolcarbonsaure, 2-Hydroxy-3,6-dimetbyl-4-metboxybenzoesaure)... 

Preparation by reaction of 2-hydroxy-4-methoxy-benzoic acid with anisole in the presence of stannic chloride at 115-120° for 3-4 h [190,237,671]. 

Benzoic acid, /(-chloro-Benzoic acid, m-hydroxy-Benzoic acid, o-hydroxy-Benzoic acid, p-hydroxy-Benzoic acid, mercapto-Benzoic acid, methoxy-Benzoic acid, methyl-Benzoic acid, o-, m-, and... 

All cements that contain eugenol inhibit the polymerization of acrylates, and those of EBA-eugenol are no exception. In order to remedy this and other defects, Brauer and his coworkers examined alternatives to eugenol (Figure 9.7). These included the esters of vanillic acid (3-methoxy-4-hydroxybenzoic acid, HV) and syringic acid (3,5-dimethoxy-4-hydroxy-benzoic acid). Both are 3-methoxy-4-hydroxy compounds and are thus chemically related to eugenol and guaiacol. Both are solids and have to be dissolved in EBA where they form satisfactory cements with EBA zinc oxide powder. The vanillate (EBA-HV) cements are the more important. 

Figure 12.12 THM GC/MS curves of a Winsor Newton lemon alkyd paint (a) and of an alkyd sample taken from Fontana s work Concetto spaziale (1961) (b). Peak assignments 1, 1,3 dimethoxy 2 propanol 2, 1,2,3 trimethoxy propane 3, 3 methoxy 1,2 propandiol 4, 4 chloro benzenamine 5, 3 methoxy 2,2 bis(methoxymethyl) 1 propanol 6, 3 chloro N methyl benzenamine 7, 3 methoxy 2 methoxymethyl 1 propanol 8, 4 chloro N methyl benzenamine 9, phthalic anhydride 10, 3 chloro 4 methoxy benzenamine 11, suberic acid dimethyl ester 12, dimethyl phthalate 13, azelaic acid dimethyl ester 14, sebacic acid dimethyl ester 15, palmitic acid methyl ester 16, oleic acid methyl ester 17, stearic acid methyl ester 18, 12 hydroxy stearic acid methyl ester 19, 12 methoxy stearic acid methyl ester 20, styrene 21, 2 (2 methoxyethoxy) ethanol 22, 1,1 oxybis(2 methoxy ethane) 23, benzoic acid methyl ester 24, adipic acid dimethyl ester 25, hexadecenoic acid methyl ester 26, dihydroisopimaric acid methyl ester 27, dehydroabietic acid methyl ester 28, 4 epidehydroabietol...

Phenolic acids Benzoic acid derivatives OH Caffeic acid 1 Gentisic acid Benzoic acid 1 1 Vanllic acid Protocatechuic acid 1 /7-Hydroxybenzoic acid COOH Syringic acid Hydroxy-isochromans HO. l-phenyh6,7- dihydroxy-isochroman l-(3 -methoxy-4- hydroxyphenyh6,7- dihydroxydsochroman R1... 

This does not occur in the case of catalyst and reactants here described. With Bronsted-type catalysis, the reaction between the benzoyl cation, Ph-C" =0, and the hydroxy group in phenol is quicker than the electrophilic substitution in the ring. This hypothesis has been also confirmed by running the reaction between anisole and benzoic acid in this case the prevailing products were (4-methoxy)phenylmethanone (the product of para-C-benzoylation) and methylbenzoate (obtained by esterification between anisole and benzoic acid, with the co-production of phenol), with minor amounts of phenylbenzoate, phenol, 2-methylphenol and 4-methylphenol. Therefore, when the 0 atom is not available for the esterification due to the presence of the substituent, the direct C-acylation becomes the more favored reaction. 

P-D-Glucopyranosyloxy-2-methoxy-6-hydroxy-benzoic acid-2 -p-D-glucopyranosyl-oxybenzylester Leiocarposide... 

Benzoic acid, o bromo-, 58, 56 Benzoic acid, 4-bromo-, 56, 86 Benzoic acid, fcrr-butyl ester, as impurity m fcrfbuty111 thium, 55, 125 Benzoic acid, 4-chloro-, 56, 86 Benzoic acid, 2,4-dimethoxy-, 56, 31 Benzoic acid, 3,4-dimethoxy-, 56, 31 Benzoic acid, 3,4-dimethyl-, 56, 31 Benzoic acid 3,5-dimethyl-, 56, 86 Benzoic acid, 4-hydroxy, 56, 60 Benzoic acid, 4-methoxy-, methyl ester, 55,40... 

Compound retention during RP-HPLC depends on the relative hydrophobicity of the sample compounds. As expected, the elution of phenolics for reversed-phase HPLC is in the order of decreasing polarity. Polarity is increased most by hydroxyls at the 4-position, followed by those at the 2- and 3-positions. Availability of the methoxy group and the acrylic substitution reduces polarity and increases retention times (4). Loss of polar hydroxy groups and/or addition of methoxy groups can decrease the polarity within each class of benzoic and cinnamic acid. Also, the presence of the ethylenic side chain in the cinnamic acids can reduce their polarity compared with similarly substituted benzoic acids (6). The elution order for benzoic acids is as follows (Table 1) gallic > a-resorcylic > protocatechuic > y-resorcylic > gentisic > p-hydroxyben-... 

Under a nitrogen blanket, a mixture of 3 g of 4-(2-piperidinoethoxy)benzoic acid hydrochloride, 2 drops of dimethylformamide, 2.5 ml of thionyl chloride and 40 ml of chlorobenzene was heated at 70°-75°C for about one hour. The excess thionyl chloride and 15-20 ml of solvent were then distilled off. The remaining suspension was cooled to ambient temperature, and to it were added 100 ml of dichloromethane, 2.7 g of 6-methoxy-2-(4-methoxyphenyl) benzo[b]thiophene and 10 g of aluminum chloride. The solution was stirred for about one hour, 7.5 ml of ethanethiol was added, and the mixture was stirred for 45 minutes more. Then 40 ml of tetrahydrofuran was added, followed by 15 ml of 20% hydrochloric acid, with an exotherm to reflux. Fifty ml of water and 25 ml of saturated aqueous sodium chloride was added. The mixture was stirred and allowed to cool to ambient temperature. The precipitate was collected by filtration and washed successively with 30 ml of water, 40 ml of 25% aqueous tetrahydrofuran, and 35 ml of water. The solids were then dried at 40°C under vacuum to obtain 5.05 g of product, which was identified by NMR as 6-hydroxy-2-(4-hydroxyphenyl)-3-[4-(2-piperidinoethoxy)benzoyl] benzo[b]thiophene hydrochloride melting point 217°C. 

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