Taxol, a substance originally isolated from the Pacific yew tree (Taxus brevifolia) more than two decades ago, has recently been approved for the clinical treatment of cancer patients. Hailed as having provided one of the most significant advances in cancer therapy, this molecule exerts its anticancer activity by inhibiting mitosis through enhancement of the polymerization of tubulin and consequent stabilization of microtubules. The scarcity of taxol and the ecological impact of harvesting it have prompted extension searches for alternative sources including semisynthesis, cellular culture production and chemical synthesis. The latter has been attempted for almost two decades, but these attempts have been thwarted by the magnitude of the synthetic challenge. Here we report the total synthesis of taxol by a convergent strategy, which opens a chemical pathway for the production of both the natural product itself and a variety of designed taxoids.

The first cycloparaphenylene (CPP)-based ionic donor-acceptor supramolecule Li(+)@C60⊂[10]CPP⋅X(-) has been synthesized. X-ray crystallography not only confirmed the molecular structure of Li(+)@C60⊂[10]CPP⋅X(-) but also uncovered the formation of a unique ionic crystal. The strong charge-transfer interaction between [10]CPP and Li(+)@C60, which was confirmed by electrochemical measurement and spectroscopic analyses, caused significant delocalization of the positive charge across the entire complex.

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We have derived preliminary results for the source process of the March 11, 2011 off the Pacific coast of Tohoku Earthquake (the 2011 Tohoku Earthquake; M w = 9.0) from two types of seismic waveform data: teleseismic P waves and regional strong motion data. The common features of these two analyses are as follows: (a) The main rupture is located to the east of the initial break point (the shallower side of the hypocenter), and maximum slip amounts were more than 25 m. (b) The size of the main fault was about 450 km in length and 200 km in width; the duration of rupture was more than 150 s; and M w was 9.0. (c) The initial rupture gradually expanded near the hypocenter (0-40 s) and subsequently propagated both southwards and northwards.