Analytical parameters^a.

LC			MS
RRLC	Agilent 1200		MS	Agilent 6410 QQQ
Isocratic mobile phase	45% ACN		ESI	Positive ESI
	10 mM NH4COOH	55%		Drying gas: N2 of low purity at 12 L min−1, pressure (60 psi)
		pH: 4.2
	Flow rate: 0.2 mL min−1
	Injection volume: 1 μL
Agilent Eclipse plus C18 column	100 mm long			Source T: 350 °C
	2.1 mm internal diameter			Capillary V: 4000 V
	1.8 μm particle size		Collision cell	N2 (high purity)
	T: 20 ± 2 °C.		Mode	MRM
Mass spectra segment	0.0 to 1.2 min	Flow to waste	Analyte: naquotinib (NQT)	m/z 563 → m/z 463, FVb: 125 V, CEc: of 22 eV
	1.2 to 2.7 min	NQT MRM		m/z 563 → m/z 323, FV: 130 V, CE: of 18 eV
	2.7 to 4.0 min	FTB MRM	Foretinib (IS)	m/z 633 → m/z 128, FV: 145 V, CE: 20 eV

^aLC, liquid chromatography; MS, mass spectrometry.

^bFragmentor voltage.

^cCollision energy.