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Mesoporous heterogeneous santa barbara amorphous (SBA)‐15‐supported cobalt complex, as a novel nanocatalyst containing N–O chelating Schiff‐base ligand was successfully synthesized by the reaction of SBA‐15 and Cobalt(II)‐Schiff‐base complex. The Co(II)‐Schiff base complex also was prepared for the first time, by the reaction of pyridoxal 5′‐phosphate or PLP (biological active form of vitamin B6), 3‐(aminopropyl)‐triethoxysilane in methanol that complexation with CoCl2. The subsequent grafting of entitled complex to SBA‐15 afforded Co(II)‐PLP‐Schiff base/SBA‐15 mesoporous catalyst. Characterization of the product was carried out with powder X‐ray diffraction, Brunauer–Emmett–Teller nitrogen adsorption–desorption, transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, atomic absorption spectroscopy, and inductively coupled plasma, Fourier‐transform infrared spectroscopy. The results revealed the retention of the textural properties and hexagonally uniform structures of SBA‐15 during the grafting procedure. This nanocatalyst was applied successfully for one‐pot synthesis of various benzothiazole heterocycles under green conditions. This catalyst is an active, reusable, and stable nanomaterial with no leaching of metal ions to the reaction medium. It was used for the synthesis of desired benzothiazole heterocycles by the cyclo‐condensation of aryl‐aldehydes with 2‐aminothiophenol with good to excellent yields and under green conditions. [ABSTRACT FROM AUTHOR]

To obtain new polyfunctional inhibitors of radical-chain oxidative processes, C- and N-benzylation of a number of phosphorylacetic acid hydrazide derivatives is realized in their reactions with 3,5-di-tert-butyl-4-hydroxybenzyl acetate. N-benzylation of mixtures of Z and E isomers of hydrazones of phosphorylacetic acid derivatives proceeds stereoselectively with the formation of only EC=N isomers. [ABSTRACT FROM AUTHOR]

New nitrogen-containing derivatives of pyridoxal were obtained as a result of its reaction with various amines. The reactions with amines bearing a heterocyclic fragment (pyridine, pyrimidine, quinoline, piperidine) furnished the final products stabilized in an aminoacetal form. The product prepared from 2-aminomethylpiperidine has an imidazolidine fragment in the molecule. [ABSTRACT FROM AUTHOR]

New salt structures have been synthesized from pyridoxal and various organic and inorganic acids. [ABSTRACT FROM AUTHOR]

The reaction of pyridoxal with 2,4-dihydroxybenzaldehyde in a hydrochloric acid solution gave 1-(5-formyl-2,4-dihydroxyphenyl)-7-hydroxy-6-methyl-1,3-dihydrofuro[3,4-c]pyridin-5-ium chloride. Treatment of the latter with sodium hydride in ethanol afforded a free aldehyde in 85% yield. A series of azomethines and imidazolidines was obtained by reacting the obtained aldehyde with various amines and diamines. [ABSTRACT FROM AUTHOR]

2-(2-Hydroxyaryl)imidazolidines were synthesized by reaction of aromatic carbonyl compounds with N, N′-dialkylethylenediamines. The title compounds were also prepared using the corresponding Schiff bases instead of carbonyl compounds. Phosphorylation of 2-(2-hydroxyphenyl)imidazolidines with phosphoryl and phosphorothioyl chlorides and phosphorochloridites was accomplished. The reaction of O-phosphorylsalicylaldehyde with N, N′-dialkylethylenediamines also afforded 2-(2-hydroxyphenyl)imidazolidines. [ABSTRACT FROM AUTHOR]

The author describes the phosphorous containing schiff bases which are used as ligands for metal complexes. These were obtained by a step-wise reaction followed by salicylaldehyde with 2-chloro-5,5-dimethyl-1,3,2λ5-dioxaphosphinane 2-sulfide then its product with 2-aminophenol gave schiff base which was phosphorylated to give tridentate ligand. In addition, if the product reacts with 2-aminobenzyl alcohol, then the phosphorus-containing benzoxazine is formed.

Interaction of pyridoxal (3-hydroxy-5-hydroxymethyl-2-methylisonicotinaldehyde) with amines, mono- and disubstituted diamines led to the formation of compounds having in their structure imine, imidazolidine, and pyrimidine moieties. Structure of the obtained compounds was proved by IR data, H NMR spectroscopy, mass spectrometry, and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented that discusses reactions of diphenylchlorothiophosphinate with pyridoxalimines.

The synthesis of pyridoxal acetal salts and the controlled-release of the alcohols in the presence of neutral pH water is described. The rate of release was monitored by 1H NMR and was found to be dependent on the concentration of water in the sample. The acetal salts are stable in the absence of moisture and show promise as a vitamin-based pro-fragrance delivery system. [ABSTRACT FROM AUTHOR]

Reactions of pyridoxal with benzoic acid and its derivatives in alcoholic medium afforded alkoxyfuropyridinium salts with potential biological activity. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented that discusses 1,3-benzoxazines and some of their reactions.

The article discusses a study on the reaction of free pyridoxal with phosphorous acid in alcoholic medium. Topics discussed include the role of pyridoxal in the form of pyridoxal 5'-phosphate in biochemical processes from protozoa to humans and the formation of crystalline compounds 2a-2e with sharp melting points from the reactions of equimolar amounts of pyridoxal and phosphorous acid in alkanols.

The article discusses a study about the potential of O-phosphorylate azomethines which are of definite interest as ligands for metal complexes design. The study obtained azomethine II via reaction of the phosphorylated salicylic aldehyde I with ortho-aminophenol. It used elemental analysis, mass spectrometry, and infrared spectrometry (IR) and nuclear magnetic resonance spectroscopy (NMR) spectroscopy to confirm the composition and structure of the compounds.

A letter to the editor in response to the article "Pyridoxal-derived Schiff's bases," that was published in a previous issue of the journal is presented.

A letter to the editor is presented in response to the article about metal complexes on hydroxyl bisazomethines in the August 11, 2014 issue.

A letter to the editor is presented in response to the article related to the synthesis of aminofuropyridines through the reaction of aminosilanes with pyridoxal.

A letter to the editor in response to the article "Dihydrofuropyridines in reactions of pyridoxal imine with 2-chloro-1,3,2-dioxaphosphorinanes," that was published in a previous issue of the journal is presented.

A letter to the editor in response to the article "Interaction of ethylenechlorophosphite with hydroxyl-containing azomethines," that was published in a previous issue of the journal is presented

A letter to the editor is presented regarding the use of phosphorus-containing macrocycles in supramolecular chemistry for studying the molecular recognition processes and complex formation.

A letter to the editor is presented in response to the article regarding the phosphorus-containing bisazomethines on terephthalic aldehyde as tetradentate ligand.