Methyl 3-amino-5-hydroxybenzoate

Procaine, on the other hand, is an ester-type local anesthetic when it is injected into the organism, it is transformed into N,N-diethylaminoethanol and para-amino-benzoic acid (PABA) when the ester link that binds these two components of procaine is broken. PABA is a well-known allergen. Methyl para-hydroxybenzoate, whose structure is similar to that of PABA, is also called PAB or methylparaben. It is a preservative that binds, like a hapten, to the immunoglobulin E (IgE) on the surface of mast cells and basophils and maybe the cause of the few cases of anaphylactic shock that have been described. Other patients may be allergic to metabisulfite conservative, found in preparations containing adrenaline (epinephrine). 

The ansa-chain of the ansamycins streptovaricins (4), rifamycins (263), geldanamycin (4), and herbimycin (32) has been shown to be polyketide in origin, being made up of propionate and acetate units with the 0-methyl groups coming from methionine. The remaining aromatic C N portion of the ansamacroHdes is derived from 3-amino-5-hydroxybenzoic acid (264—266) which is formed via shikimate precursors. Based on the precursors of the rifamycins and streptovaricins isolated from mutant bacteria strains, a detailed scheme for the biosynthesis of most of the ansamacroHdes has been proposed (95,263). 

CN a-[[bis( 1 -methylpropyl)amino]methyl]-1 -[(2-chlorophenyl)methyl]-1 //-pyrrole-2-methanol p-hydroxybenzoate (1 1)... 

Protection of carboxylic acids. The 2-(2-pyridyl)ethyl group is useful for protection of amino acids. The esters are obtained by reaction with 1 and DCC/1-hydroxybenzo-triazole. The group provides higher solubility in protic solvents, and is stable to both acids and bases. It is removed by treatment with methyl iodide and a weak base. 

C7H7N03 4-aminO 2 hydroxybenzoic acid 65-49-6 28.40 1.2744 2 10810 C7H8N202 2-methyl-4-nitroaniiine 99-52-5 140.00 1.1586 1... 

C7H7N03 5-amino-2-hydroxybenzoic acid 89-57-6 28.40 1.2744 2 10811 C7H8N202 2-methyl-5-nitroaniline 99-55-8 92.67 1,2333 2... 

C7H7N03 3-amino-4-hydroxybenzoic acid 1571-72-8 28.40 1.2744 2 10813 C7H8N202 4-methyl-2-nitroaniline 89-62-3 121.00 1.1600 1... 

C8H9Br 1 (bromomethyi)-4-methyl benzene 104-81-4 25.00 1.3240 1 13750 C8H9N03 methyl 3-amino-4-hydroxybenzoate 536-25-4 38.00 1.1820 2... 

C7H7N03 2-amino-3-hydroxybenzoic acid 548-93-6 514.86 45.314 2 10786 C7H8IN 4-iodo-3-methyl aniline 4949-69-3 546.15 48.336 2... 

Main components During fermentation, vanillin (up to app. 2.5%) is formed from the odourless glucovanillin by enzymatic hydrolysis. Its aroma is rounded-off and modified by p-hydroxybenzoic acid, p-hydroxybenzaldehyde, p-hydroxybenzyl methyl ether, vanillyl alcohol, vanillic acid, cinnamic acid ester and various other trace constituents [291, 292], Also the resins, gums, amino acids and other organic acids contribute to the typical flavour of the cured beans [293[. For further constituents and characterisations of fruits from different growing areas see [294[. 

The second example of an acylation during which the acid chloride is generated in situ (67BCF88) (Scheme 12) involves the reaction of 4-aminopyrazol-3-one 30 with 2-hydroxy-5-(methoxycarbonyl)benzoic acids 47a c where phosphorus trichloride is used and gives methyl 3- [(3-oxopyrazol-4-yl)amino]carbonyl -4-hydroxybenzoates 48a c. 

It should be mentioned that several more drastic simplifications of cocaine appeared on the scene even earlier. The only survivor is ethyl p-aminobenzoate (benzocaine, Table 13-6, No. 5). The others of interest were methyl p-amino-m-hydroxybenzoate (ortho-form), which, like benzocaine, was nontoxic, highly insoluble, and therefore not suitable for parenteral administration. Orthoform has no activity on intact skin, but it was useful as a powder on painful wounds. It was superseded commercially by the position isomer p-hydroxy-m-aminobenzoate methyl ester for reasons of cost since large-scale production of orthoform (as the pure, correct isomer) presented difficulties at the time. It should be pointed out that water-soluble hydrochlorides of the aminobenzoates can be prepared however, their solutions are much too acidic to inject. 

Note The name Orthoform was applied originally to the methyl ester of 4-amino-3-hydroxybenzoic add, mp 121, which was also used as a local anesthetic. This compd now is desiguated as Orthoform Old. 

When [carboxy-i C]-3-amino-5-hydroxybenzoic acid was fed to the culture of Streptomyces verticillatus, porfiromycin labeled with at the Cg-methyl position was obtained [10]. 

Hydroxyanthranilic acid (2-amino-3-hydroxybenzoic acid) may be substituted at the functional groups, e.g., by methylation or by substituents forming additional rings. 

The amine 26 has been proposed as a putative intermediate in the biosynthesis of 3-amino-5-hydroxybenzoic acid and the m-CyN unit in the ansamycin antibiotics, and it has been prepared from the methyl ester-methyl glycoside of 3-deoxy-D-araWn<3-heptulosonic acid by a double inversion at C-4.31... 

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