The mol-ecule of the title compound, C(20)H(16)N(2)O(2), is centrosymmetric, the inversion center being located at the mid-point of the central azine bond. The conformation around the C=N bond is E. The whole mol-ecule (except for the H atoms) is essentially planar, with an r.m.s. deviation of 0.07 Å. In the crystal, mol-ecules are linked head-to-tail by pairs of C-H⋯O hydrogen bonds, forming i...

The tptz molecule is reduced by potassium into its anion-radical in the compound K(tptz)(2) (), whereas it is reductively coupled by SmI(2) and UI(3)(py)(4) into the bis-triazinide ligand in the dinuclear complexes [Sm(2)(tptz-tptz)(DMF)(8)][I](4).3.5DMF (.3.5DMF) and U(2)I(6)(tptz-tptz)(MeCN)(2).2MeCN (.2MeCN) where each metal ion occupies a pentadentate N(5) cavity of the [tptz-tptz](2-) ligand.

A spectrophotometric method with 3-methyl-2-benzothiazolone hydrazone hydrochloride was developed for the determination of pyridoxal and pyridoxal 5'-phosphate, and for the selective determination of each in the presence of the other. Pyridoxal and pyridoxal 5'-phosphate react with the reagent to yield the azine derivatives, which give characteristic absorption spectra. The highest extinction v...

The excited state lifetimes of DNA bases are often very short due to very efficient non-radiative processes assigned to the ππ*-nπ* coupling. A set of protonated aromatic diazine molecules (pyridazine, pyrimidine and pyrazine C4H5N2(+)) and protonated pyrimidine DNA bases (cytosine, uracil and thymine), as well as the protonated pyridine (C5H6N(+)), have been investigated. For all these molecul...

A mild method for the regioselective C2-bromination of fused azine N-oxides is presented, employing tosic anhydride as the activator and tetra-n-butylammonium bromide as the nucleophilic bromide source. The C2-brominated compounds are produced in moderate to excellent yields and with excellent regioselectivity in most cases. The potential extension of this method to other halogens, effecting C2...

The association constants of the complexes formed by two hosts containing pyrrole, amide and azine (pyridine and 1,8-naphthyridine) groups and six guests, all monoanions (Cl-, CH3CO2-, NO3-, H2PO4-, BF4-, PF6-), have been determined using NMR titrations. The X-ray crystal structure of the host N2,N5-bis(6-methylpyridin-2-yl)-3,4-diphenyl-1H-pyrrole- 2,5-dicarboxamide (1) has been solved (P21/c ...