The total syntheses of (-)-cylindrocyclophane A (1), a naturally occurring, cytotoxic [7.7]paracyclophane, and its enantiomer have been achieved in an enantiodivergent manner starting from a chiral propargyl alcohol building block using Smith's cross metathesis/ring-closing metathesis protocol as the key step. The biological evaluation of both enantiomers of cylindrocyclophane A (1 and ent-1) and its analogues indicated that the chirality of 1 is irrelevant to its cytotoxicity, which is attributed to the resorcinol motifs embedded in the robust [7.7]paracyclophane framework.

A highly efficient and practical synthetic method for the preparation of pyrone diesters was established. The pyrone diester 3c can be prepared from readily available starting materials on a multihundred gram scale. The pyrone diester 3c can easily be converted to dolutegravir sodium (1). The synthetic route demonstrated herein provides an efficient and atomeconomical synthetic method for preparing this potent anti-HIV agent.

One-dimensional rod theory is very effective as a simplified analytical approach to large scale or complicated structures such as high-rise buildings, in preliminary design stages. It replaces an original structure by a one-dimensional rod which has an equivalent stiffness in terms of global properties. The mechanical behavior of structures composed of distinct constituents of different stiffness such as coupled walls with opening is significantly governed by the local variation of stiffness. Furthermore, in structures with setback the distribution of the longitudinal stress behaves remarkable nonlinear behavior in the transverse-wise. So, the author proposed the two-dimensional rod theory as an extended version of the rod theory which accounts for the two-dimensional local variation of structural stiffness; viz, variation in the transverse direction as well as longitudinal stiffness distribution. This paper proposes how to deal with the two-dimensional rod theory for structures with setback. Validity of the proposed theory is confirmed by comparison with numerical results of computational tools in the cases of static, free vibration and forced vibration problems for various structures. The transverse-wise nonlinear distribution of the longitudinal stress due to the existence of setback is clarified to originate from the long distance from setback.

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