Professor Koji Nakanishi in Brazil

This post had to be written a while ago.

Professor Koji Nakanishi’s death meant very much to the natural products chemistry community. Needless to say, his achievements are beyond words. Two of the perhaps less-known facts of Professor Nakanishi’s career are worth of mention.

The first is his 1962 book on infrared spectroscopy, with a foreword by Professor Carl Djerassi. I was lucky in finding this book in an Ann Arbor (Michigan) old books bookstore. It is perhaps one of the best books on infrared interpretation ever written.

The book opens with an impressive statement:

“The infrared spectrum (IR) is said to be one of the most characteristic properties of a compound”.

Who would ever think in IR nowawadys representing a specific feature of an organic compound? Professor Nakanishi’s thought has to be placed in a historical context, and represents a truth until today. The fact is that IR data is very often considered of minor importance, and frequently recorded with not much care, even if state-of-art Fourier transform-based instruments are currently available. But the fact is that IR data remains a unique feature for each organic compound. Even if very similar compounds can be hardly differentiated by analysis of IR data, IR spectra of very similar, but not identical, organic compounds are distinct. The structure of sebastianine B, for example, needed a good quality IR spectrum to be completely elucidated in 2001.

The book has extensive and very well organized tables of IR functional groups. A plethora of examples are discussed in detail for relevant IR absoprtions. Very useful for teaching purposes, the book includes a set of 85 problems with answers and all the spectra included are of excellent quality.

The second story is that Professor Nakanishi visited Brazil in 1996. And I was also lucky in meeting and talking to him in person. He came to participate in a meeting to discuss a very challenging endeavour – the proposal to setup the PROBEM program in the Amazon forest, a program to explore the forest chemistry for biodiscovery.

I don’t know the details on how the meeting in Brasilia, Brazil’s capital, was organized. I went as an invited observer. Among many scholars, Professor Nakanishi and Professor Jerry Meinwald were invited as advisors. Since I knew in advance that he was coming, I took with me my copy of Professor Nakanishi’s autobiography, “A Wandering Natural Products Chemist”. He was extremely kind to sign it for me, for which I was very grateful. I remain inspired by him and his achievements. Rest in peace, Professor.