Publications | Lead optimization of a pyrazole sulfonamide series of Trypanosoma brucei N-myristoyltransferase inhibitors: identification and evaluation of CNS penetrant compounds as potential treatments for stage 2 human African trypanosomiasis

Trypanosoma brucei N-myristoyltransferase (TbNMT) is an attractive therapeutic target for the treatment of human African trypanosomiasis (HAT). From previous studies, we identified pyrazole sulfonamide, DDD85646 (1), a potent inhibitor of TbNMT. Although this compound represents an excellent lead, poor central nervous system (CNS) exposure restricts its use to the hemolymphatic form (stage 1) of the disease. With a clear clinical need for new drug treatments for HAT that address both the hemolymphatic and CNS stages of the disease, a chemistry campaign was initiated to address the shortfalls of this series. This paper describes modifications to the pyrazole sulfonamides which markedly improved blood-brain barrier permeability, achieved by reducing polar surface area and capping the sulfonamide. Moreover, replacing the core aromatic with a flexible linker significantly improved selectivity. This led to the discovery of DDD100097 (40) which demonstrated partial efficacy in a stage 2 (CNS) mouse model of HAT.

Principal Investigator(s):

Author(s):
Brand, S., Norcross, N. R., Thompson, S., Harrison, J. R., Smith, V. C., Robinson, D. A., Torrie, L. S., McElroy, S. P., Hallyburton, I., Norval, S., Scullion, P., Stojanovski, L., Simeons, F. R., van Aalten, D., Frearson, J. A., Brenk, R., Fairlamb, A. H., Ferguson, M. A

PubMed:
25412409
Citation:
Brand, S., Norcross, N. R., Thompson, S., Harrison, J. R., Smith, V. C., Robinson, D. A., Torrie, L. S., McElroy, S. P., Hallyburton, I., Norval, S., Scullion, P., Stojanovski, L., Simeons, F. R., van Aalten, D., Frearson, J. A., Brenk, R., Fairlamb, A. H., Ferguson, M. A
J Med Chem
2014
57
9855-9869
PMID: 25412409