Ibrexafungerp: an orally active β-1,3-glucan synthesis inhibitor.
Bioorg Med Chem Lett. 2020 Nov 04;:127661
Authors: Apgar JM, Wilkening RR, Parker DL, Meng D, Wildonger KJ, Sperbeck D, Greenlee ML, Balkovec JM, Flattery AM, Abruzzo GK, Galgoci AM, Giacobbe RA, Gill CJ, Hsu MJ, Liberator P, Misura AS, Motyl M, Nielsen Kahn J, Powles M, Racine F, Dragovic J, Fan W, Kirwan R, Lee S, Liu H, Mamai A, Nelson K, Peel M
We previously reported medicinal chemistry efforts that identified MK-5204, an orally efficacious β-1,3-glucan synthesis inhibitor derived from the natural product enfumafungin. Further extensive optimization of the C2 triazole substituent identified 4-pyridyl as the preferred replacement for the carboxamide of MK-5204, leading to improvements in antifungal activity in the presence of serum, and increased oral exposure. Reoptimizing the aminoether at C3 in the presence of this newly discovered C2 substituent, confirmed that the (R) t-butyl, methyl aminoether of MK-5204 provided the best balance of these two key parameters, culminating in the discovery of ibrexafungerp, which is currently in phase III clinical trials. Ibrexafungerp displayed significantly improved oral efficacy in murine infection models, making it a superior candidate for clinical development as an oral treatment for Candida and Aspergillus infections.
PMID: 33160023 [PubMed – as supplied by publisher]