Trifluoroacetic acid

33 wt% solution of HBr in HAc was supplied by Acros. Benzyloxycarbonyl chloride and trifluoroacetic acid were purchased from GL Biochem (Shanghai) Ltd. l-Lactide was purchased from PURAC Biochem by Gorinchem and recrystallized from ethyl acetate for three times. 2-Amino-1,3-propanediol was purchased from Tokyo Chemical Industry Co., Ltd. The hexane and tetrahydrofuran were dried by CaH₂ to remove water, and purged with dry nitrogen, and then passed through an activated alumina column. All other chemicals were purchased from various commercial suppliers without further purification unless otherwise stated.

Rink amide 4-methylbenzhydrylamine resin, Fmoc-protected amino acids, peptide coupling reagents, and trifluoroacetic acid (TFA) were purchased from GL Biochem (Shanghai, China). The test strains Escherichia coli (E. coli) ATCC 25922, P. aeruginosa ATCC 27853, A. baumannii ATCC 19606, S. aureus ATCC 25923, and Candida albicans (C. albicans) ATCC 10231 were purchased from the American Type Culture Collection (Manassas, VA, United States). Carbapenem-resistant P. aeruginosa (CRPA) SIPI-012 and carbapenem-resistant A. baumannii (CRAB) SIPI-025 were generously gifted by Huanshan Hospital (Shanghai, China). Red blood cells and plasma were extracted from healthy blood donors. RAW 264.7 cells were obtained from the Chinese Academy of Sciences. BALB/c mice were purchased from Shanghai SIPPR-BK Laboratory Animal Co., Ltd. Trypsin, colistin, vancomycin hydrochloride, amphotericin B, 2,2,2-trifluoroethanol (TFE), and lipopolysaccharide (LPS) from E. coli O55:B5 were purchased from Sigma. Mueller Hinton (MH) broth, RPMI 1640 medium, Dulbecco’s modified Eagle medium (DMEM), fetal bovine serum (FBS), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were obtained from Thermo Fisher Scientific.

Manse-AT, citronellol, thioanisole, dithioglycol, phenol, HPLC grade n-hexane, N,N-dimethyl-formamide (DMF), dichloromethane (DCM) and acetonitrile were from Sigma-Aldrich (St. Louis, MO, USA). Rink Amide-AM resin (0.52 mmol/g substitution), O-benzotriazole-N,N,N′,N′-tetramethyl-uronium-hexafluoro-phosphate (HOBt), 1-hydroxybenzotriazole anhydrate (HBTU), N,N′-diisopropyl ethylamine (DIEA), trifluoroacetic acid (TFA) and Fmoc-protected amino acids were purchased from GL Biochem (Shanghai, China). Juvenile hormone II and III were purchased from SciTech (Praha, Czech Republic) and Toronto Research Chemicals (Toronto, ON, Canada), respectively.