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Rationale: Mummification is one of the defining customs of ancient Egypt. The nuances of the embalming procedure and the composition of the embalming mixtures have attracted the attention of scientists and laypeople for a long time. Modern analytical tools make mummy studies more efficient., Methods: Comprehensive two-dimensional gas chromatography-high resolution mass spectrometry (GCxGC/HRMS) with complementary ionization methods (electron ionization, positive chemical ionization, and electron capture negative ionization [ECNI]) with a Pegasus GC-HRT+4D instrument was used to identify embalming components in the mummy from the Pushkin Museum of Fine Arts acquired in 1913 in London at the de Rustafjaell sale. The mummy dates back to the late Predynastic period (direct accelerator mass spectrometry-dating 3356-3098 bc), being one of the oldest in the world., Results: The results showed the complexity of the embalming mixtures that were already in use 5000 years ago. Several hundred organic compounds were identified in the mummy samples. Various types of hydrocarbons (triterpanes, steranes, isoprenoid, and polycyclic aromatic hydrocarbons) prove the presence of petroleum products. Iodinated compounds detected using ECNI define oils of marine origin, whereas esters of palmitic acid indicate the use of beeswax. The nature of the discovered components of conifer tar proves that the preliminary processing of conifer resins involved heating. GCxGC/HRMS also allowed a number of modern contaminants (phthalates, organophosphates, and even DDT) to be identified., Conclusions: Application of a powerful GCxGC/HRMS technique with complementary ionization methods allowed significant widening of the range of organic compounds used for mummification that could be identified. The complexity of the embalming mixtures supports the hypothesis of the high social status of the child made on the basis of the preliminary study of the mummy., (© 2021 John Wiley & Sons Ltd.)

Rationale: Mass spectrometry is known as an excellent method to predict the behavior of organic compounds in solution. The behavior of organic compounds in the gas phase inside the ion source of a mass spectrometer allows their intrinsic properties to be defined, avoiding the influence of intermolecular interactions, counter ions and solvent effects., Methods: Arylpyrrolidin-2-ones were obtained by condensed-phase synthesis from the corresponding N-arylcyclopropanecarboxamides. Electron ionization (EI) with accurate mass measurements by high-resolution time-of-flight mass-spectrometry and quantum chemical calculations were used to understand the behavior of the molecular radical cations of N-arylcyclopropanecarboxamides and N-arylpyrrolidin-2-ones in the ion source of a mass spectrometer. The geometries of the molecules, transition states, and intermediates were fully optimized using DFT-PBE calculations., Results: Fragmentation schemes, ion structures, and possible mechanisms of primary isomerisation were proposed for isomeric N-arylcyclopropanecarboxamides and N-arylpyrrolidin-2-ones. Based on the fragmentation pattern of the N-arylcyclopropanecarboxamides, isomerisation of the original M +• ions into the M +• ions of the N-arylpyrrolidin-2-ones was shown to be only a minor process. In contrast, this cyclization proceeds easily in the condensed phase in the presence of Brønsted acids., Conclusions: Based on the experimental data and quantum chemical calculations the principal mechanism of decomposition of the molecular ions of N-arylcyclopropanecarboxamides involves their direct fragmentation without any rearrangements. An alternative mechanism is responsible for the isomerisation of a small portion of the higher energy molecular ions into the corresponding N-arylpyrrolidin-2-one ions. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)