The CoI2(PPh3)2/Zn system effectively catalyzes the [2 + 2 + 2] ene-diyne cycloaddition of 1,6-heptadiynes with allenes in a highly regio- and chemoselective fashion to yield substituted benzene derivatives in good to excellent yields.

A new strategy for Rh(I)-catalyzed [2+2+2] cycloadditions of 1,6-diynes with potassium (Z)-(2-bromovinyl)trifluoroborate as the third two-atom unit has been realized, which provides a facile entry to polysubstituented benzene derivatives.

Hexa-substituted benzene derivatives show larger two-photon cross sections than the corresponding dipolar counterparts and the largest values of delta(max) = 2000 GM and delta(max)/MW = 2.25 GM g(-1) have been obtained with a compound having C[triple bond]C and C=C bonds in the conjugation bridge.

We have successfully developed a new synthetic approach to modulate the electrostatic potentials of metallocavitands and thus their selective recognition towards substituted benzene derivatives via integrating two metal cations of different electronegativity into a self-assembled system.

Recent reports show that a compound identified as ethyl gallate (Little et al., 1953) found in Haematoxylon campechianum is specifically inhibitory to Mycobacterium tuberculosis, strain 607 (Johnstone et al., 1953). The antimicrobial activity of gallates is not new information, for several such reports and patents are known (Sabalitschka and Tietz, 1931; Bucher, 1945; and Tollenaar, 1952); but ...

periments were therefore conducted. Various methods have already been reported for thin layer chromatography of antioxidants by Seher (1), Meyer (2), Davidek and Pokorny (3) and Jonas (4). Seher utilized a two-dimension chromatography with silica gel as the adsorbent and chloroform and benzene as the solvents for development. Gallates and related compounds and NDGA remained at the starting poin...

The ability of various tea catechins to generate H2O2 and the hydroxyl radical in the presence of the Cu2+ ion was investigated and compared with the effect of iron ions. The presence of Cu2+ accelerated the generation of H2O2 by EGC, while EGCg with Cu2+ generated a little H2O2. The presence of iron ions inhibited the generation of H2O2 by EGC. EGC and EC with Cu2+ generated the hydroxyl radic...