Separation of SORA and its degradation products (DP-1-DP-5) was achieved on Acquity UPLC BEH C18 (100 mm × 2.1 mm × 1.7 μm) column using a gradient elution of 0.1% formic acid and acetonitrile at a flow rate of 0.3 mL/min within 12 min. 
Acquity UPLC BEH C18
High resolution quadruple time-of-flight mass spectrometer (Q-TOF/MS) was utilized for characterization of all DPs. 
High resolution quadruple time-of-flight mass spectrometer (Q-TOF/MS)
In ESI/CID-MS/MS experiments, the protonated DP-1 and DP-2 exhibited few interesting product ions which provide a compelling evidence for the compounds to undergo gas phase rearrangement reaction justified by its mechanistic explanation in support with density functional theory (DFT). 
ESI/CID-MS/MS
In-source collision-induced dissociation (IS-CID) fragmentation using ESI/APCI-MS analysis exhibited the formation of N-deoxygenated product ion peak corresponds to pyridine N-oxide moiety as in DP-5. 
ESI/APCI-MS analysis
Further, major hydrolytic DPs (DP-2 and DP-3) were isolated on preparative HPLC and structural elucidation was done using ID NMR (1H, 13C and DEPT-135) experiments. 
preparative HPLC
Further, major hydrolytic DPs (DP-2 and DP-3) were isolated on preparative HPLC and structural elucidation was done using ID NMR (1H, 13C and DEPT-135) experiments. 
ID NMR