Columnar liquid crystalline bis-N-annulated quaterrylenes have been prepared from readily available N-annulated perylenes by DDQ/Sc(OTf)(3) oxidative coupling and ring-fusion.

Sequential biomimetic elaborations, featured by CrO(3)-mediated oxidative lactonization, and DDQ-involved oxidative enol-lactonization, ensured the concise total synthesis of (+)-chloranthalactone F.

formation of the molecular complexes between meso-tetraphenylporphyrin (tpp) and the p-acceptors 2,3-dichloro-5,6-dicyanobenzoquinone (ddq) and tetracyanothylene (tcne) in chloroform solution was investigated spectrophotometrically. the formation constants of the resulting 1:1 molecular complexes were determined using the benesi-hildebrand and nash methods. the tpp-ddq proved to be more stable ...

A spectrophotometric study concerning the interaction between Trimethoprim (TMP) ,Sulfamethoxazole (SFMx), as n-donor and 2,3-dichloro-5,6- dicyano-P-benzoquinine (DDQ) and chloranilic acid (CA) as π-acceptor were been performed at 25°C. The results of interaction of CA and DDQwith TMP indicate the formation of a 1:1, 1:2, charge transfer complexes through non equilibrium reactions. In the case...

the interaction between benzo-15-crown-5 (b15c5), dibenzo-18-crown-6 (db18c6), dibenzyl-daza-18crown-6 (dbzda18c6), n-phenyl-aza-15-crown-5 (npha15c5) and dibenzopyridine-18-crown-6 (dbpy18c6) with π-acceptor 2,3-dichloro-5,6-dicyanobenzoquinone (ddq) in chloroform solution was studied spectrophotometrically. the interaction of b15c5-ddq and db18c6-ddq caused the formation of 1:1 charge transfe...

The spin-state of cytochrome b559 (cyt b559) was studied in photosystem II (PSII) membrane fragments by low-temperature EPR spectroscopy. Treatment of the membranes with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) converts the native low-spin (LS) form of cyt b559 into the high-spin (HS) form characterized by the g = 6.19 and g = 5.95 split signal. The amount of HS cyt b559 was pH dependent w...

Two simple, selective, and rapid spectrophotometric methods are described for the determination of mycophenolate mofetil (MPM) in pure form and in tablets. Both methods are based on charge-transfer complexation reaction of MPM with p-chloranilic acid (p-CA) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dioxane-acetonitrile medium resulting in coloured product measurable at 520 nm (p-CA)...

We herein described an intramolecular imino Diels-Alder reaction promoted with BF(3).OEt(2)/DDQ affording substituted quinolines. Using this procedure, we prepared the chiral quinoline moiety of the uncialamycin, a new enediyne natural product.