Highly Practical and Simple Ligand for Separation of Am(III) and Eu(III) from Highly Acidic Media.

A new, high-performance, highly practical, simple reagent called alkyl diamide amine (ADAAM) was examined for the separation of Am(III) and Eu(III). ADAAM has three donor atoms, one soft N-donor atom and two hard O-donor atoms, on a central frame. The combination of soft and hard donor atoms affords a tridentate that ensures remarkable extraction ability and selectivity of Am(III) and Eu(III) from highly acidic media (1.5 M HNO3) with a separation factor up to 25.

Biological activity of alpha-thujaplicin, the isomer of hinokitiol.

alpha-Thujaplicin, a minor component of Aomori Hiba (Thujopsis dolabrata SIEB. et ZUCC. var. hondai MAKINO), showed rather strong antifungal activity against seven kinds of plant-pathogenic fungi, their minimum inhibitory concentrations (MICs) being in the range of 12.0-50.0 microg/ml. alpha-Thujaplicin and hinokitiol (the major component of Aomori Hiba) also showed clear antibacterial activity against Legionella pneumophila SG 1 and L. pneumophila SG 3, and their MICs are in the range of 6.25-50 microg/ml. This compound showed strong insecticidal activity against Reticulitermes speratus [50%-lethal concentration (LC(50)): 0.02 g/m(2)], and it also had clear acaricidal activity against Dermatophagoides farinae (LC(50): 0.66 g/m(2)). At 24 h after treatment, alpha-thujaplicin at 0.63 microg/ml inhibited the cell growth of murine P388 lymphocytic leukemia by 78%, and its cytotoxic activity at a concentration higher than 0.63 microg/ml was as high as that of vincristine, used as a positive control. On the other hand, the cytotoxic effect of alpha-thujaplicin at 0.63 microg/ml was weaker than that of vinblastine. In this respect, the strong cytotoxic effect of alpha-thujaplicin on murine P388 lymphocytic leukemia cell line should be emphasized, considering that it has recently been found to be low in toxicity to mice.

Biological activity of tropolone.

Tropolone (1). showed strong insecticidal activity on Tyrophagus putrescentiae and Dermatophagoides farinae. The insecticidal effect of 1 on both insects was stronger than that of hinokitiol (2, 4-isopropyltropolone: major component of Thujopsis dolabrata SIEB. et ZUCC. hondai MAKINO). The insecticidal activity of both compounds was higher than that of N,N-diethyl-m-toluamide (DEET), used as a positive control. Compound 1 had potent insecticidal activity against Coptotermes formosanus, although its activity was much lower than that of commercial chloropyrifos. Like 2, 1 showed the inhibitory activity toward metalloproteases such as carboxypeptidase A, collagenase and thermolysin and their inhibitory activities were much higher than that of 1,10-phenanthroline, used as a positive control. The inhibitory activity of 1 on carboxypeptidase A was especially high, its 50% inhibitory concentrations (IC(50)) being 2.73 x 10(-6) M. This inhibitory activity was as high as that of 2 (IC(50): 2.76 x 10(-6) M). Compound 1 inhibited the growth of seven kinds of plant-pathogenic fungi and their minimum inhibitory concentration (MIC) values were in the range of 6.0-50.0 microg/ml. In particular, 1 showed strong antifungal activity on Pythium aphanidermatum IFO-32440 (MIC: 6.0 microg/ml).