A detailed procedure for the analysis of exogenous dehydroepiandrosterone (DHEA) in urine by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) has been established for detecting doping with DHEA. The average delta-value (parts per thousand difference of (13)C/(12)C ratio from the isotope ratio standard) of 26 synthetic steroids commercially available was -30.1 +/- 2.6, and was significantly lower than that of human endogenous DHEA in urine of the world class athletes who had participated in the XVIIth Olympic Winter Games (-20.3 +/- 2.1, n = 446). Although large inter-individual variations of urinary DHEA excretion were observed following a single oral administration of 50 mg of DHEA, no significant inter-individual difference was found when the excretion of exogenous DHEA was monitored in terms of delta-values using GC/C/IRMS; the minimum delta-values were observed around 6-8 h after the administration, and the values returned to the base level at over 72 h after the dosing. Thus, the deviations in delta-values of DHEA and its diol metabolites are considered to be conclusive evidence for detecting doping with DHEA. Some successful cases of detection of doping with DHEA from athletes are also reported.

While nonracemic catalysts can generate nonracemic products with or without the nonlinear relationship in enantiomeric excesses between catalysts and products, racemic catalysts inherently give only a racemic mixture of chiral products. Asymmetric catalysts, either in nonracemic or racemic form, can be further evolved into highly activated catalysts with association of chiral activators. This asymmetric activation process is particularly useful in racemic catalysis through selective activation of one enantiomer of the racemic catalyst. Recently, a strategy whereby a racemic catalyst is selectively deactivated by a chiral additive has been reported to yield nonracemic products. However, reported herein is an alternative and conceptually opposite strategy in which a chiral activator selectively activates, rather than deactivates, one enantiomer of a racemic chiral catalyst. The advantage of this activation strategy over the deactivation counterpart is that the activated catalyst can produce a greater enantiomeric excess in the products—even with the use of a catalytic amount of activator relative to chiral catalyst—than that attained by the enantiomerically pure catalyst on its own. Therefore, asymmetric activation could provide a general and powerful strategy for not only the use of atropisomeric, racemic ligands but also chirally flexible and proatropisomeric ligands without enantiomeric resolution!

Chiral tetranuclear Ti cluster, a cubic structure constituted of four Ti atoms and OHs, and six (R)-binaphthols (BINOL) bridged two Ti atoms as ligands, is shown to be a novel chiral Lewis acid catalyst for the [2+3] cycloaddition reaction with nitrones. The chiral Ti clusters with 7,7'-substituted (R)-BINOL ligands was synthesized to give enhanced enantiomeric excesses up to 78% ee.

Damage-less full molecular-pore-stack SiOCH (MPS) / Cu interconnect is developed to reduce effective k-value (k eff ).MPS with high endurance against plasma processes is introduced into both via and trench dielectrics without hard mask (HM). Low friction slurry and chemical modification of MPS surface by He-plasma treatment suppress defect generation during direct CMP of the MPS surface. The full-MPS interconnect with low-k (k=3.1) cap demonstrates 10% lower inter-line capacitance and 34% lower inter-layer capacitance than the full-SiOCH (k=3.0) interconnect with SiCN-cap (k=4.9). The effective k-value k eff reduces to 2.67 for the damage-less full MPS structure which is applicable to 32nm LSIs and beyond.

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