Recently, in connection with the remarkable development of computational technologies for rational drug designs, the necessity has become apparent of rapid measurement or estimation of molecular properties of chemicals having a potential for medical use. In particular, hydrophobicity (as expressed by the logarithm of 1-octanol/water partition coefficient, log P oct ) is identified as one of the most important properties that govern potencies; its prediction has attracted much attention from medicinal chemists, agrochemists and many investigators in various fields such as pharmacology, toxicology, environmental chemistry and food chemistry. 1,2)Instead of measuring log P oct by the standard but time-consuming shake-flask method, reversed-phase chromatography (RP-HPLC) has increasingly been used as a powerful tool to predict log P oct from the readily accessible retention factor, log k, (given by kϭ(t R Ϫt 0 )/t 0 where t 0 and t R express elution times of the non-retained substance and sample, respectively).Extensive studies have been made to establish an optimal RP-HPLC system providing a good linearity between log P oct and log k.3-10) Many workers have used an ODS-type column with methanol-water mobile phases to obtain a normalized parameter, log k W (k W : the retention factor extrapolated to 0% organic modifier), as an alternative to log P oct . 3,5,8) In our experience, this log k W approach works well for non-polar solutes but tends to provide overestimated log P oct values for strong H-acceptors. [10][11][12][13][14][15] From systematic studies of log k obtained under various HPLC conditions for typical heteroaromatic compounds such as (di)azines, furans and thiophenes, we were led to the conclusion that the use of an eluent containing around 50% methanol, which usually provides a more direct correlation with log P oct , is the most convenient and practical procedure for rapid estimation of log P oct provided H-donors (amphiprotic compounds) are treated separately.11-15) Our results so far obtained are illustrated graphically in Fig. 1. This conclusion has been derived from the following results.First, we have shown that, for each series of monosubstituted (di)azines, log P oct can be excellently correlated with log k in different compositions of methanol-water eluents by a general formula Eq. 1 containing two terms correcting for H-bonding effects: 16) log kϭalog P oct ϩrs I ϩsS HA ϩconst.( 1) where the s I parameter represents the Charton's inductive electronic substituent constant, 17) and S HA designates the substituent H-acceptor scale that we have recently defined where the value of S HA is set at unity for H (the unsubstituted * To whom correspondence should be addressed. The use of log k derived from reversed phase (RP)-HPLC retention times provides a convenient method for estimating log P oct values (P oct : 1-octanol/water partition coefficient). In order to establish optimal HPLC conditions, the difference between chromatographic (C18 modified column and aqueous methanol eluents) and bulk solve...

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Due to the lingering aftermath of a nuclear catastrophe being mostly out of sight, the peripheral victims of the Fukushima disaster were no longer able to discern the boundary between the here of the safety zone and the there of the afflicted area. What ensued after this geographical unification was psychological unity in which the harmony-conscious ethics of the Japanese were excessively fortified, formulating what is often called the code of wa (harmonious integration), which implicitly coerced all to speak from hisaisha no tachiba (the standpoint of the afflicted people). Kyoko Iwaki, a doctoral student at Goldsmiths, University of London, after fourteen years as a theatre journalist in Japan, provides in this article a socio-psychological analysis on how the code of wa materialized as the unwritten law after the catastrophe, and argues how in Current Location (Genzaichi), playwright-director Okada Toshiki grapples with this code by developing a post-Fukushima aesthetic. By pertinently using the apparatus of ‘fiction’ as a guise for relieving the audience of the code, Okada develops a theatre language that voices discord in content, yet accord in form, permitting the characters to speak both from the here and the there.

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