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The cyclization-carbonylation of alkynyl hydrazones (I) proceeds readily in the presence of palladous trifluoroacetate in DMSO leading to pyrazole-4-carboxylates (IV) in good to high yields.

Palladium and CO: Carbonylation of 1 with [Pd(tfa)2(±)-L1] (tfa = trifluoroacetate) affords the spirofuranone 2 with inversion of the stereochemistry at C17 in 96 % yield. C17-epi-1 also gave the same product 2 with retention of the stereochemistry at C17. Labelling studies show that (13)CO was incorporated into the C5' position of the furanone ring. The first asymmetric version of this new reaction was achieved.

A pair of tetracycline-resistant Staphylococcus aureus strains carrying different resistance determinants, tetK and tetM, were employed to screen some ginseng prosapogenins as antagonists of tetracycline resistance. The tetK gene encodes TetK efflux pump and the tetM gene define a ribosomal-level resistance. The susceptibility of two strains to tetracycline was measured in parallel in the presence of various concentrations of test compounds. The efflux pump not ribosomal protection was adversely affected by ginsenosides Rh 2 , F 1 , 20-O-β-D-glucopyranosyl20(S)-dammar-3, 20-diol (compound K), 20(R)-ginsenoside Rh 2 and their aglycones at nontoxic concentrations, reversing tetracycline resistance in the tetK-carrying S. aureus.

Palladium(II) catalyzed carbonylation of 1,2-allenyl ketones 1 in the presence of p-benzoquinone (1 equiv) under a CO atmosphere (balloon) afforded difuranylketones 4 in moderate to good yields. Mechanistically, the electron-withdrawing nature of the acyl group should enhance the electrophilicity of the acylpalladium species B, and thus promote the oxypalladation of an additional molecule of 1, leading to the difuranyl ketone 4.

Since 1969, authors have been doing a statistical analysis of airborne pollen grains, aiming at the clarification of their atmospheric behaviors, in connection with an increase in a number of pollinosis cases. The airborne pollens were collected three times a week starting from January 1 and ending December 31 with the help of cascade impactor, by which 6001 of air was suctioned at the rate of 51 per min for 2 h from 10:00 a.m. to 12:00 at the rooftop of one of the buildings (16 m high) in the Narashino Campus of Toho University, Funabashi, Chiba. The collected airborne pollens were numerated and classified under microscope according to the Ikuse's classification system for Japanese pollens. The number of days (n) was plotted as a function of daily number of a certain type of airborne pollens (x), not fitting to a simple normal distribution. However, the data were found to approximate a normal distribution when x was log-transformed as ln (x + 1). Among the statistical methods tested, semilogarithmic plot, Weibull plot, Edwards' plot and circular graph method were found to be useful in the follow-up of seasonal variation of environmental pollen grains, especially when used in combination.

In contrast to the formation of 2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithietane from hexafluoropropene, potassium fluoride, and sulfur, perfluoro-2-butene and perfluoro-pentenes react with potassium fluoride and sulfur to form perfluoro-1,3-dithioles via intermediate thioenolate anions.