Journal : J Med Chem
Title : Identification and Profiling of a Novel Diazaspiro[3.4]octane Chemical Series Active against Multiple Stages of the Human Malaria Parasite Plasmodium falciparum and Optimization Efforts.
Year : 2021
Volume : 64
Issue : 4.0
First Page : 2291
Last Page : 2309
Authors : Le Manach C,Dam J,Woodland JG,Kaur G,Khonde LP,Brunschwig C,Njoroge M,Wicht KJ,Horatscheck A,Paquet T,Boyle GA,Gibhard L,Taylor D,Lawrence N,Yeo T,Mok S,Eastman RT,Dorjsuren D,Talley DC,Guo H,Simeonov A,Reader J,van der Watt M,Erlank E,Venter N,Zawada JW,Aswat A,Nardini L,Coetzer TL,Lauterbach SB,Bezuidenhout BC,Theron A,Mancama D,Koekemoer LL,Birkholtz LM,Wittlin S,Delves M,Ottilie S,Winzeler EA,von Geldern TW,Smith D,Fidock DA,Street LJ,Basarab GS,Duffy J,Chibale K
Abstract : A novel diazaspiro[3.4]octane series was identified from a Plasmodium falciparum whole-cell high-throughput screening campaign. Hits displayed activity against multiple stages of the parasite lifecycle, which together with a novel sp-rich scaffold provided an attractive starting point for a hit-to-lead medicinal chemistry optimization and biological profiling program. Structure-activity-relationship studies led to the identification of compounds that showed low nanomolar asexual blood-stage activity (<50 nM) together with strong gametocyte sterilizing properties that translated to transmission-blocking activity in the standard membrane feeding assay. Mechanistic studies through resistance selection with one of the analogues followed by whole-genome sequencing implicated the P. falciparum cyclic amine resistance locus in the mode of resistance.