*2.2. UHPLC–HR-MS Experiment*

The full-scan UHPLC–qTOF-MS analysis (positive mode) of the blotter paper methanol extract revealed the TIC of a relatively complex mixture, in accordance with what had been observed in the GC–MS analysis (Figure S2). The extraction of the ion chromatogram (XIC) with the [M + H]<sup>+</sup> of 1B-LSD (*m*/*z* 394.249), as received from the LC–qTOF-MS analysis, revealed a clear and significant peak. The analytical system allowed for a chromatographic separation to be performed whilst producing untargeted (all-ion mode) MS<sup>2</sup> spectra (Figure 3).

**Figure 3.** U(H)PLC–qTOF-MS (**A**) full-scan MS (**B**) untargeted MS<sup>2</sup> spectrum of *m*/*z* 394.249 ([M + H]+) of the extract.

For the Orbitrap-MS experiments, the sample extract was directly infused into the system for analysis. Full-scan MS was performed initially, with a multitude of ions being found, as the blotter paper methanol extract, containing several components, was injected directly. In fact, the lack of a chromatographic technique coupled to the Orbitrap, increased the complexity of the results. However, the previous results, indicating the possible presence of 1B-LSD, allowed an oriented extraction of its protonated molecular ion [M + H]+, which was found and confirmed as m/z 394.25004. After this analysis, the ion was isolated and fragmented successively (MS2, MS3 and MS4), and Figure 4 shows the fragmentation spectrum of this ion (MS2).

**Figure 4.** MS2 spectrum from Infusion to Orbitrap MS of the extract [selected molecular ion *m*/*z* was 394.25004 assigned to the protonated molecular mass [M + H]+.

Some of the fragments identified with the Orbitrap-MS analysis are also consistent with those of the GC–MS, even if different ionization modes were used (ESI+ vs. EI+). All the identification was based on spectral data (Agilent MassHunter), the literature and the application of chemo-informatics tools (ACD/Labs Spectrus Processor and MS Fragmenter), a software platform that allows the prediction of fragmentation and the comparison of experimental with theoretical data. The resulting identification of the most relevant fragments, as received from the chemo-informatics tool for the Orbitrap-MS, are presented in Table 2. All results were consistent with both the qTOF-MS fragmentation and the fragmentation patterns of 1B-LSD, as reported by Brandt et al. [9].


**Table 2.** Orbitrap-MS-identified fragments for 1B-LSD (ACD/Spectrus Processor 2017.2.1).

<sup>1</sup> *m*/*z* Exp.: experimental *m*/*z*; <sup>2</sup> RI Exp. (%): Relative Intensity (%) of experimental *m*/*z*.
