728865-23-4

CHIR-090 is a potent, slow, tight-binding inhibitor of the LpxC deacetylase. It binds to E. coli LpxC with a Ki of 4.0 nM. CHIR-090 is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.

ChEBI: CHIR-090 is an L-threonine derivative obtained by formal condensation of the carboxy group of 4-({4-[(morpholin-4-yl)methyl]phenyl}ethynyl)benzoic acid with the amino group of N-hydroxy-L-threoninamide. It has a role as an antimicrobial agent, a lipopolysaccharide biosynthesis inhibitor and an EC 3.5.1.108 (UDP-3-O-acyl-N-acetylglucosamine deacetylase) inhibitor. It is an acetylenic compound, a member of morpholines, a member of benzamides, a L-threonine derivative and a hydroxamic acid.

General procedure for the synthesis of N-((2S,3R)-3-hydroxy-1-(hydroxyamino)-1-oxobutan-2-yl)-4-((4-(morpholinomethyl)phenyl)ethynyl)benzamide from CHIR090-Intermediate 1: To a stirred anhydrous methanol (5 mL) of hydroxylamine hydrochloride (400 mg, 5.76 mmol) at 0 °C and under nitrogen protection solution was slowly added sodium methanol (25 wt% methanol solution, 1.860 g, 8.60 mmol). After the reaction mixture was stirred at 0 °C for 20 min, a 1:1 methanol/THF (6 mL) solution of methyl ester 4 (829 mg, 1.90 mmol) was added. Subsequently, the reaction mixture was continued to be stirred at 0°C for 1 hr and then brought to room temperature and stirred for 4 hr. Upon completion of the reaction, the reaction was quenched with 1.0 M hydrochloric acid (6 mL), the organic solvent was removed by concentration by rotary evaporation, and the residue was diluted with DMSO (4 mL). Analytical reversed-phase high-performance liquid chromatography (RP-HPLC, C18 column, acetonitrile gradient 5-35% with 0.1% trifluoroacetic acid, UV detection wavelength 300 nm, run time 16 min) showed a purity of 85% for the crude product mixture. Purification of the crude product by preparative RP-HPLC and lyophilization of the collected fractions gave the target compound 5 (701 mg, 81% yield) as a fluffy white solid. Low resolution mass spectrometry (ESI+) m/z 438.1 (calculated value of 438.20 for C24H27N3O5+H); reversed-phase high-performance liquid chromatography (300 nm, 16-minute run time) retention time was 8.7 minutes.

LpxC

[1] Barb AW, et al. Inhibition of lipid A biosynthesis as the primary mechanism of CHIR-090 antibiotic activity in Escherichia coli. Biochemistry. 2007 Mar 27;46(12):3793-802. DOI:10.1021/bi6025165
[2] Barb AW, et al. Structure of the deacetylase LpxC bound to the antibiotic CHIR-090: Time-dependent inhibition and specificity in ligand binding. Proc Natl Acad Sci U S A. 2007 Nov 20;104(47):18433-8. DOI:10.1073/pnas.0709412104
[3] Tan JH, et al. In Vitro and In Vivo Efficacy of an LpxC Inhibitor, CHIR-090, Alone or Combined with Colistin against Pseudomonas aeruginosa Biofilm. Antimicrob Agents Chemother. 2017 Jun 27;61(7). pii: e02223-16. DOI:10.1128/AAC.02223-16