[Medicinal chemistry for macromolecules]
>>Published online before print November 15, 2004
Proc. Natl. Acad. Sci. USA, 10.1073/pnas.0404802101
Biochemistry
Medicinal chemistry applied to a synthetic protein: Development of highly potent HIV entry inhibitors
( AIDS | CCR5 | chemokines )
Oliver Hartley a,b, Hubert Gaertner a,b,c, Jill Wilken d,e, Darren Thompson d,f, Richard Fish a,g, Alejandra Ramos h, Cristina Pastore h, Brigitte Dufour a, Fabrice Cerini a, Astrid Melotti a, Nikolaus Heveker i,j, Laurent Picard i,k, Marc Alizon i, Donald Mosier h, Stephen Kent d,l, and Robin Offord a,m
aDepartment of Structural Biology and Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland; dGryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, CA 94080; hDepartment of Immunology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037; and iDepartment of Cell Biology, Institut Cochin, Institut National de la Santé et de la Recherche Médicale U567, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8104, 22 Rue Méchain, 75014 Paris, France
Edited by James A. Wells, Sunesis Pharmaceuticals, Inc., South San Francisco, CA, and approved October 6, 2004 (received for review July 6, 2004)
We have used total chemical synthesis to perform high-resolution dissection of the pharmacophore of a potent anti-HIV protein, the aminooxypentane oxime of [glyoxylyl1]RANTES(2-68), known as AOP-RANTES, of which we designed and made 37 analogs. All involved incorporation of one or more rationally chosen nonnatural noncoded structures, for which we found a clear comparative advantage over coded ones. We investigated structure-activity relationships in the pharmacophore by screening the analogs for their ability to block the HIV entry process and produced a derivative, PSC-RANTES {N-nonanoyl, des-Ser1[L-thioproline2, L-cyclohexylglycine3]-RANTES(2-68)}, which is 50 times more potent than AOP-RANTES. This promising group of compounds might be optimized yet further as potential prophylactic and therapeutic anti-HIV agents. The remarkable potency of our RANTES analogs probably involves the unusual mechanism of intracellular sequestration of CC-chemokine receptor 5 (CCR5), and it has been suggested that this arises from enhanced affinity for the receptor. We found that inhibitory potency and capacity to induce CCR5 down-modulation do appear to be correlated, but that unexpectedly, inhibitory potency and affinity for CCR5 do not. We believe this study represents the proof of principle for the use of a medicinal chemistry approach, above all one showing the advantage of noncoded structures, to the optimization of the pharmacological properties of a protein. Medicinal chemistry of small molecules is the foundation of modern pharmaceutical practice, and we believe we have shown that techniques have now reached the point at which the approach could also be applied to the many macromolecular drugs now in common use.<<
Cheers, Tuck |
