To pay tribute to Lemont B. Kier in this special issue of CCADD is an honor and a joy. Monty and I have been associated for
many years, but his influence on my scientific life began well before we met.
The year was 1970, and my mind was occupied with two major projects, writing up my PhD thesis and finding a suitable
institution abroad for post-doctoral studies. At that time, I saw -- and immediately bought -- a book edited by L.B.K and
entitled “Molecular Orbital Theory in Chemical Pharmacology: A Symposium held at Battelle Seattle Research Center”. This
book, together with seminal works in stereochemistry and SAR, brought me for two years to the (now closed) Chelsea College
of Science and Technology, University of London, where I was fortunate to learn my future trade under the inspiring and
dedicated guidance of the late Prof. Arnold H. Beckett.
It was there, on September 26, 1972, that I saw Monty for the first time. He had been invited by the Society for Drug Research
to visit Chelsea College and give a formal lecture on “Conformation and drug action”. The large lecture hall was packed and
left me no chance to interact with Monty, but the impression he made was indelible.
Our first face-to-face meeting had to wait for another 16 years to occur. Indeed, Monty was one of the distinguished speakers at
the 7th European QSAR Symposium chaired by my late and dear friend Jean-Luc Fauchere and held in Interlaken (Switzerland)
in September 1988. Remarkably, a highlight of this Symposium was the celebration of the 70th birthday of Corwin Hansch.
During this Symposium, I had long discussions with Monty and I even recall an outing with him and his wife Martha along the
shore of the lake of Brienz. After the Symposium, they came to visit us in Lausanne – and this is where and when our long
collaboration began. At that time, Monty's research interests had shifted toward electrotopological indices and were beginning
to extend into physicochemical simulations using cellular automata. The latter area of research, together with musings on
complexity, clinched our collaboration.
During the 1989-2003 period, Monty spent eleven summers as a visiting scientist in our Institute of medicinal chemistry,
totaling twenty-five months of presence! Of special note is his election in 1992 to the Chair of Honor of the University of
Lausanne, indeed a very rare recognition. During his stays, Monty was busy carrying out his own research, but he was also
most generous with his time, advising graduate students, giving numerous seminars and collaborating with the undersigned.
The visible fruit of his collaboration was the joint publication of sixteen research papers and seven reviews, a selection of
which appears at the end of this text.
For more than five decades now, Monty has been a pioneer in computational studies. His earlier work on conformational
factors in structure-activity relationships supplied the missing stepping-stone toward a realistic three-dimensional understanding
of pharmacophores. His subsequent creation and development of electrotopological indices allowed fast encoding of
stereoelectronic features and in silico high-throughput screening of chemical libraries. Cellular automata simulations, his last
pet topic, have been less practical in the questions they addressed. Their main value, in my view, is the didactic and inspiring
insights they allow. Each of these three fields would have filled the career of a gifted medicinal chemist. But Monty is more
than a gifted scientist – he is a discoverer and leader. The worldwide community of medicinal chemists owes much to him, as
this timely special issue of CCADD testifies.
 Fan, W.; El Tayar, N.; Testa, B.; Kier, L.B. Water-dragging effect: a new experimental hydration parameter related to hydrogen-bond donor acidity. J.
Phys. Chem., 1990, 94, 4764-4766.
 Testa, B.; Kier, L.B. The concept of molecular structure in structure-activity relationship studies and drug design. Med. Res. Rev., 1991, 11, 35-48.
 Tsai, R.S.; Fan, W.; El Tayar, N.; Carrupt, P.A.; Testa, B.; Kier, L.B. Solute-water interactions in the organic phase of a biphasic system. I. Structural
influence of organic solutes on the “water-dragging” effect. J. Am. Chem. Soc., 1993, 115, 9632-9639.
 Kier, L.B.; Cheng, C.K.; Testa, B.; Carrupt, P.A. A cellular automata model of the hydrophobic effect. Pharm. Res., 1995, 12, 615-620.
 Kier, L.B.; Cheng, C.K.; Testa, B.; Carrupt, P.A. A cellular automata model of micelle formation. Pharm. Res., 1996, 13, 1419-1422.
 Kier, L.B.; Cheng, C.K.; Testa, B.; Carrupt, P.A. A cellular automata model of enzyme kinetics. J. Molec. Graphics, 1996, 14, 227-231.
 Testa, B.; Kier, L.B.; Carrupt, P.A. A systems approach to molecular structure, intermolecular recognition, and emergence-dissolvence in medicinal
research. Med. Res. Rev., 1997, 17, 303-326.
 Kier, L.B.; Cheng, C.K.; Testa, B.; Carrupt, P.A. A cellular automata model of aqueous diffusion. J. Pharm. Sci., 1997, 86, 774-778.
 Kier, L.B.; Cheng, C.K.; Testa, B. A cellular automata model of the percolation process. J. Chem. Inform. Comput. Sci., 1999, 39, 326-332.
 Testa, B.; Raynaud, I.; Kier, L.B. What differenciates free amino acids and amino acyl residues ? An exploration of conformational and lipophilicity
spaces. Helv. Chim. Acta, 1999, 82, 657-665.
 Kier, L.B.; Cheng, C.K.; Testa, B. Cellular automata models of biochemical phenomena. J. Future Generation Computer Systems, 1999, 16, 273-289.
 Testa, B.; Kier, L.B. Emergence and dissolvence in the self-organization of complex systems. Entropy, 2000, 2, 1-25. *Free access:
 Testa, B.; Kier, L.B.; Cheng, C.K. A cellular automata model of water structuring by a chiral solute. J. Chem. Inform. Comput. Sci., 2002, 42, 712-716.
 Kier, L.B.; Cheng, C.K.; Testa, B. A cellular automata model of ligand passage over a protein hydrodynamic landscape. J. Theor. Biol., 2002, 215,
 Kier, L.B.; Cheng, C.K.; Testa, B. Studies of ligand diffusion pathways over a protein surface. J. Chem. Inform. Comput. Sci., 2003, 43, 255-258.