A. Eschenmoser

Chemistry of potentially prebiological natural products

A relationship between what might be called a kinetic version of Le Chateliers principle and chemical self-organization is considered. Some aspects of the search for a pre-RNA genetic system are discussed. Results of an experimental investigation on the pairing properties of alternative nucleic acid systems — including those of pyranosyl-RNA (‘p-RNA’), a constitutional isomer of RNA — are summarized.

Porphyrin synthesis by ring transplantation

Abstract One of the four equivalent pyrrole rings of octaethyl porphyrinogen has been replaced by a foreign pyrrole ring in one operation and in (relatively) good yield.

Thoughts and Experiments on a Chemical Etiology of Nucleic Acid Structure

Organic chemists enamoured with the science and art of chemical syntheses can’t help being fascinated again and again by the power of the language of organic chemistry. It is a language which makes it possible to model virtually the entire world of organic molecules with a handful of very simple rules. More and more, it also becomes the biologists’ language, whenever their research problems lead them down to the molecular level of the chemist. At this symposium, we honour one of the creators of this language, Josef Loschmidt, and we do so by reflecting on the history of the ideas that had led to it more than a century ago, and by illustrating the paramount role this graphic language of organic chemistry plays in our time.