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abstracts
The quinol 4-(1-benzenesulfonyl-1H-6-fluoroindol-2-yl)-4-hydroxycyclohexa-2,5-dienone (1) is strongly active against cancer cells [1]. Two "Michael acceptor" electrophilic β-carbons on the quinol ring are believed necessary for optimal antitumor activity, and disruption of thioredoxin signaling is a possible mechanism of action. As a model for the possible product, the adduct (2) with two molecules of ethanethiol was prepared. These molecules have just one classical hydrogen bond (HB) donor group, the quinol OH, but a surfeit of acceptors, namely one C=O and two SO2 oxygen atoms (designated O15, O17 and O18) as well as O14, the OH itself. In (1) paired molecules form a R22(14) ring by O14-H...O17 HB with H...O distance 2.15 Å and O-H...O angle 156°. In (2) the two EtS groups on the same side of the quinol ring as O14 interfere with this motif. Instead, a C(7) chain is formed by less optimal O14-H...O17 HB (2.34 Å and 134°). In apparent compensation, an intramolecular C-H...O HB to O17 is shorter and straighter in (2). In both structures all O atoms accept C-H...O HB. The unit cell dimensions are dissimilar, but a motif persists: one phenyl CH and one indole CH group bite onto the same O atom, O15 in (1) but O18 in (2).
abstracts
It is appropriate that 2014 has been chosen as the International Year of Crystallography since it was a century ago that crystallography as we know it emerged as a truly international science. The pattern becomes clearer if one considers academic years starting on September 1. Thus 1911-1912, when the first successful diffraction experiments were carried out, becomes the German year of crystallography. With the statement of Bragg's Law and the first structure determinations, 1912-1913 can be called the British year of crystallography. By late 1913 our science had achieved truly international scope, demonstrated by publications describing advances in experimental design, theory and structure determination emanating from France, Japan, the Netherlands, Russia and Switzerland as well as Germany and Britain. While many countries worked on the first two areas, structure determination was done mainly in Britain (dominated by the Braggs) and Japan (to a limited extent). In the belligerent countries this magnificent flowering was sadly curtailed by the outbreak of World War I. However, at about this time the United States entered the field. The international spread followed by curtailment is readily visualised when presented in the form of a timeline.
