2,6-pyridinedicarboxylate

When reacted with tetraalkylammonium halides, hydrated [Me2Sn(IV)], [Bu2Sn(IV)]2-",2 [Ph2Sn(IV)]2-", 5 and [EtPhSn(lV)]2-",2 ester derivatives of 2,6-pyridinedicarboxylic acid yield tetraalkylammonium diorganohalogeno(2,6-pyr-idinedicarboxylato)stannates. Both classes of compounds exhibit high in vitro antitumor activity. 

A review by Galli et al. describes several buffer-absorbing chromophores as co-ions. These include phthalate, PDG (2,6-pyridinedicarboxylic acid), PMA (1,2,4,5-benzenetetra-carboxylic acid or pyromellitic acid), TMA (trimellitic acid), MES, 2,4-dihydrobenzoic acid with s-aminocaproic acid, p-hydroxybenzoate, p-anisate, 3,5-dinitrobenzoic acid, salicylic acid with TRIS, benzoic acid with tris (hydroxymethyl)aminomethane (TRIS), and many others. On the other hand, some inorganic chromophores such as chromate (Figure 9) or molybdate may be added to a buffer. A BGE-containing chromate should have a pH above 8, because it precipitates below this value. The advantage of a TRIS buffer or buffers at around pH 6 is that carbonate will not interfere with the separation because it is not soluble in TRIS or at lower pHs. 

Figure 10.5. Adsorbate molecular orientation at the electrode surface d) nicotinic acid (Z ) benzoic acid (c) 2,6-pyridinedicarboxylic acid. (From Ref. 12, with permission from the American Chemical Society.)...

Pyridinedicarboxylic acid (dipicolinic acid) is a widely used building block in coordination and supramolecular chemistry. The crystal stractrrre of dipicolinic acid was first solved in 1973, which confirmed its molectrlar formtrla of C7H5NO4, a molar mass of 167.119 g mol , and the resrrlting composition of its constituent atoms (C, 50.31% H, 3.02% N,... 

More reeently, there was a report on the use of dipicolinic acid in the design of layered crystalline materials using coordination chemistry and hydrogen bonds. MaeDonald et al. reported the synthesis and characterization of several first-row transition metals with dipicolinic acid as a ligand. Five bis(imidazolium 2,6-pyridinedicarboxylate)M(II) trihydrate complexes (where M = Mn, Co, Ni, Cu, or Zn ), were synthesized from the reaction between dipicolinic acid and imidazole with Mn, Co, ... 

A very simple yet elegant method for efficient epoxidation of aromatic and aliphatic alkenes was presented by Beller and coworkers [63, 64], FeCl3 hexahydrate in combination with 2,6-pyridinedicarboxylic add and various organic amines gave a highly reactive and selective catalyst system. An asymmetric variant (for epoxidations of trans-stilbene and related aromatic alkenes) was published recently [65] using N-monosulfonylated diamines as chiral ligands (Scheme 3.7). 

Ding, M., Tanaka, K., Hu, W., Haddad, P. R., and Miyanaga, A. (2001) Simultaneous Determination of Anions and Cations in Environmental Samples by Using a Weakly Acidic Cation-exchange Column with 2, 6-pyridinedicarboxylic Acid, Sulfosalicylic acid, and 18-crown-6 as Eluent, J. Liq. Chromatogr. Rel. Techn. 24, 3105-3117. 

Iwahashi H, Kawamori H, Fukushima K. Quinolinic acid, a-picolinic acid, fusaric acid, and 2,6-pyridinedicarboxylic acid enhance the Fenton reaction in phosphate buffer. Chem-Biol Interact 1999 118 201-215. 

Figure 11 Speciation of V using an Alltech Adsorbosphere 5-pm SCX column and inductively coupled plasma mass spectrometry (ICP-MS) detection using single-ion monitoring at m z 51 eluent, 2,6-pyridinedicarboxylic acid (7.0 mmol/L) and lithium hydroxide (9.6 mmol/L) at pH 4.0 flow rate, 1.5 mL/min and injected amount 12.5 ng. (From Ref. 71.)...

The systems described above all involve peroxometal species as the active oxidant. In contrast, ruthenium catalysts involve a ruthenium-oxo complex as the active oxidant [1]. Until recently, no Ru-catalysts were known that were able to activate H202 rather then to decompose it. However in 2005 Beller and co-workers recognized the potential of the Ru(terpyridine)(2,6-pyridinedicarboxylate) catalyst [63] for the epoxidation of olefins with H202 [64]. The result is a very efficient method for the epoxidation of a wide range of alkyl substituted or allylic alkenes using as little as 0.5 mol% Ru. In Fig. 4.26 details are given. Terminal... 

Six-coordination is observed in [PhPbCl5]2-90 while 7-coordination is seen in (Ph)2Pb(2,6-pyridinedicarboxylate)(H20)2.91... 

The structure of a typical complex with 2,6-pyridinedicarboxylate as ligand is (17-A-IV), where the 0—0 distance, 1.46 A, is that of a i72-peroxo ligand (Section 11-10). 

The p-anisyloxymethyl group520 (abbreviated AOM) played an important role in the synthesis of Calicheamicinone reported by Clive and co-workers.521 Its removal from the sensitive multifunctional substrate 285 1 [Scheme 4.285] was accomplished with CAN in a mixture of pyridine, methanol and water. The excellent yield (89%) attests to the mildness of the conditions. Attempts to apply the same conditions to the deprotection of an AOM group from 286 1 [Scheme 4.286]522 failed but the deprotection was successful if it was conducted in the presence of 2,6-pyridinedicarboxylic acid N-oxide — conditions previously used to convert a phenol methyl ether to a quinone.523 AOM ethers undergo easy reductive cleavage to the corresponding methyl ethers with borane in toluene — a reaction that could have synthetic value when simple O-methylation procedures fail. 

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