K2 edta

1,2-dipentadecanoyl-sn-glycero-3-phosphoethanolamine (PE 15:0/15:0), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (PE 16:0/18:1(9Z)), 1-(1Z-octadecenyl)-2-arachidonoyl-sn-glycero-3-phosphoethanolamine (PE P-18:0/20:4(5Z,8Z,11Z,14Z)), 1-tridecanoyl-sn-glycero-3-phosphoethanolamine (LPE 13:0/0:0) were purchased from Avanti Polar Lipids (Alabaster, AL, USA). All of them were >99% pure, except LPE 13:0/0:0 may contain up to 10% of sn-2 isomer. [U-¹³C₆]-D-glucose (99%) was from Cambridge Isotope Laboratories (Tewksbury, MA, USA). D-glucose and all solvents including methanol (MeOH), acetonitrile (ACN), isopropanol (IPA), chloroform (CHCl₃), and water (H₂O) of LC-MS grade and HPLC grade were purchased from Fisher Scientific (Pittsburgh, PA, USA). Pooled human plasma collected from healthy people with K2-EDTA as anticoagulant was purchased from BioIVT (Westbury, NY, Lot#: BRH1524451). The standard reference material—metabolites in frozen human plasma (NIST SRM-1950)—was purchased from the NIST (Gaithersburg, MD).

The chemicals 5-(6,6-dimethyl-4-morpholino-8,9-dihydro-6H-[1,4]oxazino[4,3-e]-purin-2-yl)pyrimidin-2-amine (GDC-0084; Figure 1a) and 5-(6,6-bis(methyl-d₃)-4-morpholino-8,9-dihydro-6H-[1,4]oxazino[4,3-e]-purin-2-yl)pyrimidin-2-amine [GDC-0084-d₆, internal standard (ISTD); Figure 1b] were from Genentech (San Francisco, CA, USA). Ammonium formate (MS grade, ≥ 99.0%) was purchased from Millipore Sigma (St. Louis, MO, USA). Dimethyl sulfoxide (molecular biology grade), formic acid (LC-MS/MS grade, 99.5% purity), acetonitrile (ACN) (HPLC grade), and methanol (HPLC grade) were purchased from Fisher Scientific (Waltham, MA, USA). The Millipore Q-advantage water purification system (Temecula, CA, USA) was used to prepare the water used in all experiments. Human whole blood and human plasma, with K2-EDTA as an anticoagulant, and human CSF were purchased from BioIVT (Westbury, NY, USA).