2-Amino-3,6-dihydroxy-benzoic acid

This highly substituted p-benzoquinone derivative tends to prevail at high pH values and also at pH 7 when the autoxidation products are checked after several hours [35], It certainly arises from a nucleophilic attack by OH on the quinoneimine C. This attack is obviously increasingly easy as the pH arises, and leads to 2-amino-3,6-dihydroxy-benzoic acid, which is in turn oxidised to the corresponding quinone. This is attacked at the 5 position by a molecule of still unreacted HA, and the corresponding adduct is finally oxidised to the stable final product I, Fig. 

In a recent modification of the second synthesis (50S) effected for fluvibactin (45) an o-xylene protection group was proposed (reaction of 2,3-dihydroxy-benzoic acid methyl ester with 1,2-di(bromomethyl)benzene) which could be removed later by hydrogenolysis. The formation of the oxazoline ring from protected DHB-L-threonine methyl ester was achieved with Mo(VI) catalysts (e.g. (NH4)2Mo04) without affecting the chiral centers. Derivatization of the primary amino groups of norspermidine with the protected DHB methyl ester was catalyzed by Sb(OC2115)3. 

Chemical Name 2-[(7-Chloro-4-quinolinyl)amino] benzoic acid 2 3-dihydroxy-propyl ester Common Name Glycerylaminophenaquine Structural Formula ... 

The 3-amino-4,7-dihydroxy-coumarin moiety is a core unit of this family of compounds. The amino group of coumarin scaffold is further decorated with derivatives of pyrrole or benzoic acid moieties. Also, branched deoxysugar 5-C-methyl-L-rhamnose (noviose) is installed onto one of the hydroxyls of the coumarin. Clorobiocin 67 and novobiocin 68 can be considered prototypical aminocoumarins. These molecules are potent inhibitors of bacterial gyrase and topo-isomerase IV and 68 is used to treat human infections. Several works also showed that analogs of 68, in combination with other drugs, can improve the chemotherapy of certain tumors [121]. 

BENZOIC ACID, 4-BENZOYL- see BDL860 BENZOIC ACID, BENZYL ESTER see BCMOOO BENZOIC ACID-n-BUTYL ESTER see BQK250 BENZOIC ACID, CHLORIDE see BDM500 BENZOIC ACID, 2,4-DIHYDROXY- (9CI) see HOE600 BENZOIC ACID,2-((3-(4-(l,l-DIMETHYLETHYL)PHENYL)-2-METHYLPROPYLIDENE)AMINO)-, METHYLESTER see LFTIOO... 

At the branching point of chorismic acid, either anthranilic acid, the precursor of tryptophan, or prephenic acid, the precursor of phenylalanine, itself the precursor of tyrosine and dopa (3,4-dihydroxy-phenylalanine), is formed (Fig. 10). Phosphorylation at the 3-position, condensation with phosphoenolpyru-vate, and elimination of phosphoric acid yields choris-mate from shikimate. Chorismate is also the precursor of a number of simple, and very important, aromatic compounds, including salicylic acid, 4-amino-benzoic acid (PABA), a constituent of folic acid, and 2,3-dihydroxybenzoic acid, a key acylating group of enterobactin. 

Benzoic acid, 4-amino-, triester with 2,4-dihydroxy-N-(3-hydroxypropyl)-3,3-dimethylbutanamide. SeeTripaba panthenol Benzoic acid, ammonium salt. See Ammonium benzoate... 

See Diethylene glycol dibenzoate Benzoic acid diester with dipropylene glycol. See Dipropylene glycol dibenzoate Benzoic acid, 2-(1-(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl) amino) carbonyl)-2-oxopropyl) azo). See Pigment yellow 151 Benzoic acid, 2,5-dihydrox-. See Gentisic acid Benzoic acid, 3,4-dihydroxy-5-[[3,4,5-tris[(1-oxo-9-octadecenyl) oxy] benzoyl] oxy]-, (Z,Z,Z)-. 

It has been found by experiment that substances of the type RX, containing two different haptenic groups, do not form precipitates with either anti-R serum or anti-X serum Alone, but do form precipitates with a mixture of the two specific antisera. This provides proof of the effective bivalence of the dihaptenic precipitating antigen, and thus furnishes further evidence for e framework theory of antigen-antibody precipitation. In these experiments tiie anti-R serum and anti-X serum were made by injecting rabbits with sheep serum coupled with diazotized p-arsanilic add and diazotized p-aminobenzoic acid, respectively, and the RX substances used were l-amino-2-/>-(p-azophenylazo)-phenylarsonic acid-3,6-disul-fonic add 7-p-(p-azophenylazo)-benzoic acid-8-hy-droxynaphthalene and l,8-dihydroxy-2-/>-azo-phenylarsonic acid-3,6-disulfonic acid-7-p-(p-azo-phenylazo)-benzoic acid-naphthalene. 

UVA 2,2 -dihydroxy-4-methoxybenzophenone 2-(2H-benzotriazol-2-yl)-p-cresol 2-benzotriazol-2-yl-4,6-di-tert-butylphenol phenol, 2-(5-chloro-2H-benzotriazole-2-yl)-6-(1,1 -dimethylethyl)-4-methyl- 2-(2H-benzotriazole-2-yl)-4,6-di-tert-pentylphenol 2-(2H-benzotriazole-2-yl)-4-(1,1,3,3-tetraethylbutyl)phenol 2-(2H-benzotriazol-2-yl)-4,6-bis(1 -methyl-1 -phenylethyl)phenol 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol, branched linear 2,4-di-tert-butyl-6-(5-chloro-2H-benzotriazole-2-yl)-phenol 2-(3-sec-butyl-5-tert-butyl-2-hydroxyphenyl) benzotriazole reaction product of methyl 3(3-(2H-benz-otriazole-2-yl)-5-t-butyl-4-hydroxyphenyl propionate/PEG 300 ethyl-2-cyano-3,3-diphenylacrylate (2-ethylhexyl)-2-cyano-3,3-diphenylacrylate N-(2-ethoxyphenyl)-N -(4-isododecylphenyl)oxamide N-(2-ethoxyphenyl)-N -(2-ethylphenyl)oxamide benzoic acid, 4-[[(methylphenylamino) methylene]amino]-, ethyl ester Screeners carbon black ... 

Catechol, hydroquinone, resorcinol, dihydroxy-phenylalaninc, p-hydroxydiphenyl, guaiacol, va-nillan, p-crcsol, mcsitol, durenol, pyrogallol Benzoic, salicylic, protocatechuic, gallic, p-amino benzoic acids... 

Amino-4,7-dihydroxy- [4-Hydroxy-3 (3-methyl-2-8-methyl coumarin] butenyl)benzoic acid]... 

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