Picolinic 5-hydroxy

CAS 65-23-6 EINECS/ELINCS 200-603-0 Synonyms 4,5-Bis-hydroxymethyl-2-methyl pyri di n-3-ol 4,5-Di methylol-3-hydroxy-2-methylpyridine 3-Hydroxy-4,5-dimethylol-o-picoline 5-Hydroxy-6-methyl-3,4-pyridinedimethanol 3-Hydroxy-2-picoline-4,5-dimethanol... 

In 1965, Breslow and Chipman discovered that zinc or nickel ion complexes of (E)-2-pyridinecarbaldehyde oxime (5) are remarkably active catalyst for the hydrolysis of 8-acetoxyquinoline 5-sulfonate l2). Some years later, Sigman and Jorgensen showed that the zinc ion complex of N-(2-hydroxyethyl)ethylenediamine (3) is very active in the transesterification from p-nitrophenyl picolinate (7)13). In the latter case, noteworthy is a change of the reaction mode at the aminolysis in the absence of zinc ion to the alcoholysis in the presence of zinc ion. Thus, the zinc ion in the complex greatly enhances the nucleophilic activity of the hydroxy group of 3. In search for more powerful complexes for the release of p-nitrophenol from 7, we examined the activities of the metal ion complexes of ligand 2-72 14,15). 

Wu, K.J. Steding, A. Becker, C.H. Matrix-Assisted Laser Desorption-TOF-MS of Oligonucleotides Using 3-Hydroxy-picolinic Acid As an Ultraviolet-Sensitive Matrix. Rapid Commun. Mass Spectrom. 1993, 7,142-146. 

Photodecomposition products included acidic compounds and five methylated derivatives (Plimmer, 1970). When picloram in an aqueous solution (25 °C) was exposed by a high intensity monochromatic UV lamp, dechlorination occurred yielding 4-amino-3,5-dichloro-6-hydroxy-picolinic acid which underwent decarboxylation to give 4-amino-3,5-dichloropyridin-2-ol. In addition, decarboxylation of picloram yielded 2,3,5-trichloro-4-pyridylamine which may undergo dechlorination yielding 4-amino-3,5-dichloro-6-hydroxypicolinic acid (Burkhard and Guth, 1979). 

An interesting rearrangement is involved in the reaction between N-hydroxy-iV JV" diphenylguanidine (225), toluenesulfonyl chloride, and y-picoline in benzene at 0°. This yields a colorless toluenesulfonate which with alkali gives red anhydro-s-triazolo[4,3-a]pyridinium hydroxide (226), which is a derivative of meso-ionic l,2,4-triazol-3-imine (216). ... 

Analogous to the tautomerism of the hydroxy- and amino-pyridines (Sections 3.2.3.7.1 and 3.2.3.5.5), there are alternative tautomeric alkylidene forms of the 2- and 4-alkylpyridines e.g. 609 for 2-picoline). Although the proportion of alkylidene form at equilibrium is very small (as is discussed in Section 2.2.5.1.2), it can be important as a reactive intermediate (see above). 

Large rate accelerations have been observed in the metal ion-promoted hydrolysis of some lactams and these reactions are considered in Section 61.4.10. Other investigations have dealt with divalent metal ion-catalyzed hydrolysis of p-nitrophenyl picolinate in the presence of imidazoles and pyridines having hydroxyl groups in their side chains,226 the zinc(II)-facilitated hydrolysis of esters of 2-hydroxy acids227 and the metal ion-promoted hydrolysis of methyl 2-( JV-acetylhydrazono) propanoate.228... 

Sigman and Jorgenson490 have found that zinc(II) catalyzes the transesterification reaction between N- (/3-hydroxy ethyl) ethylenediamine and 4-nitrophenyl picolinate. This reaction involves a reactive mixed ligand complex (152) in which the zinc(II) ion perturbs the p/fa of the hydroxyethyl group of N-(/3-hydroxyethyl)ethylenediamine to provide a high effective concentration of the nucleophile. Intramolecular nudeophlic attack then occurs at the carbonyl group of p-nitrophenyl picolinate. This system provides a somewhat unique example of intramolecular... 

The hydrolysis at 25 °C of p-nitrophcnyl picolinate (71) catalysed by the Cu(II) complex of 4-chloro-2,6-di(iV-hydroxyethylaminomethyl)phenol (72 R = CH2NH CH2CH2OH) was studied kinetically at different pH in the presence of three surfactants hexadecyltrimethylammonium bromide, sodium lauroylsarcosinate, and polyoxyethylene (23) lauryl ether.69 The Cu(II) complexes of two iV-alkyl-3,5-di(hydroxy-methyl)-1,2,4-triazoles (73 R = CioH2i, Ci2H2s) were better than the Ni(II) complexes as catalysts for the hydrolysis of p-nitrophcnyl picolinate (71) in CTAB micelles.70... 

Hydroxylation of pyridine in unspecified yield has been effected by passing the vapors over potassium hydroxide powder at 300-320°.302 2-Picoline is hydroxylated at C-6 in this way,303 and 3-hydroxy-pyridine gives 2,3-dihydroxypyridine.102... 

Mixed complex formation kinetics between LnEDTA and L, where L stands for 5-sulfosalicylate [74], 8-hydroxy quinoline-5 sulfonate and picolinate [75] were studied and two pathways namely acid-dependent and acid-independent pathways have been identified. The overall reaction stoichiometry may be written as... 

C6H5N03 p-nitrophenol 100-02-7 489.15 42.843 2 7018 C6H6N203 2-hydroxy-5-nitro-3-picoline 21901-34-8 377.15 32.218 2... 

C14H15N30 N-hydroxy-N-ethyl-p-(phenylazo) aniline 58989-02-9 438.25 37.984 1.2 27364 C14H16N40 4-((4-(dimethylamino)-m-tolyl)azo)-2-picolin 7347-47-9 553.15 49.014 2... 

Various reports in the literature indicate the influence of endocrine organs on tryptophan metabolism. Chiancone and co-workers (C5, V2) reported that ovariectomy or hypophysectomy of rats caused increased excretion of xanthurenic acid and that adrenalectomy caused a decrease. An adrenal mechanism is suggested for the regulation of 3-hydroxy-anthranilic acid conversion to nicotinic and picolinic acids (M7). 

Oxalic acid (3 structures)/Carbonate/ Bipyridine (4 structures)/Picolinic acid/3-hydroxy-picolinic acid/2,4-pyridine dicarboxylic acid/3-acetatoxy-picolinic acid/5-nitro-phenanthroline 2 26 174-183... 

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