Structure Assignment of Seized Products Containing Cathinone Derivatives Using High Resolution Analytical Techniques

The innovation of the new psychoactive substances (NPS) market requires the rapid identification of new substances that can be a risk to public health, in order to reduce the damage from their use. Twelve seized products suspected to contain illicit substances were analyzed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), gas chromatography coupled to mass spectrometry (GC-MS), and nuclear magnetic resonance spectroscopy (NMR). Synthetic cathinones (SCat) were found in all products, either as a single component or in mixtures. Infrared spectra of all products were consistent with the molecular structure of SCat, showing an intense absorption band at 1700–1674 cm−1, corresponding to the carbonyl stretching, a medium/strong peak at 1605–1580 cm−1, indicating stretching vibrations in the aromatic ring (C=C) and bands with relative low intensity at frequencies near 2700–2400 cm−1, corresponding to an amine salt. It was possible to identify a total of eight cathinone derivatives by GC-MS and NMR analysis: 4’-methyl-α-pyrrolidinohexanophenone (MPHP), α-pyrrolidinohexanophenone (α-PHP), 3-fluoromethcathinone (3-FMC), methedrone, methylone, buphedrone, N-ethylcathinone, and pentedrone. Among the adulterants found in these samples, caffeine was the most frequently detected substance, followed by ethylphenidate. These results highlight the prevalence of SCat in seized materials of the Portuguese market. Reference standards are usually required for confirmation, but when reference materials are not available, the combination of complementary techniques is fundamental for a rapid and an unequivocal identification of such substances.

Metabolite Structure Assignment of Seized Products Containing Cathinone Derivatives through High Resolution Analytical Techniques

The innovation of the new psychoactive substances (NPS) market requires the rapid identification of new substances that can be a risk to public health, in order to reduce the damage due to their use. Twelve seized products suspected to contain illicit substances were analyzed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), gas chromatography coupled to mass spectrometry (GC-MS), and nuclear magnetic resonance spectroscopy (NMR). Synthetic cathinones (SCat) were found in all products, either as a single component or in mixtures. Infrared spectra of all products were consistent with the molecular structure of SCat, showing an intense absorption band at 1700–1674 cm‐1, corresponding to the carbonyl stretching, a medium/strong peak at 1605-1580 cm-1, indicating stretching vibrations in the aromatic ring (C=C) and bands with relative low intensity at frequencies near 2700–2400 cm-1, corresponding to an amine salt. It was possible to identify a total of eight cathinone derivatives by GC-MS and NMR analysis: 4’-methyl-α-pyrrolidinohexanophenone (MPHP), α-pyrrolidinohexanophenone (α-PHP), 3-fluoromethcathinone (3-FMC), methedrone, methylone, buphedrone, N-ethylcathinone, and pentedrone. Among the adulterants found in these samples, caffeine was the most frequently detected substance, followed by ethylphenidate. These results highlight the prevalence of SCat in seized materials of the Portuguese market. Reference standards are usually required for confirmation, but when reference materials are not available, the combination of complementary techniques is fundamental for a rapid and an unequivocal identification of such substances.

FAR-INFRARED STUDIES OF THE STATE OF IONICAGGREGATION IN MIXTURES OF POLYETHERURETHANE AND K IONOMER STYRENE COPOLYMER WITH ACRYLIC ACID

Методом спектрального анализа в дальнем (70 - 420 см) ИК-диапазоне исследовано влияние введения ионных групп на формирование сетки физических связей в композитах на основе полиэфир уретана и сополимера стирола. Анализ спектров ПУИ / Ст-со-АК (К+) композитов показал, что при увеличении содержания Ст-со-АК (К+) в системе образуется новая сетка межмолекулярных (ион-молекулярных) связей. Появление интенсивной полосы поглощения при ~ 180 см, обусловленной колебаниями катионов К+ в электростатической области анионов (СОО-) карбоксильных групп, её значительная полуширина и наличие максимумов при 145, 155, 177, 185, и 200 см свидетельствуют об образовании различных по организации форм катион-анионных ассоциатов в системе: от простых ионных пар до сложных мультиплетов и кластеров. He effect of the introduction of ionic groups on the formation of a network of physical bonds in composites based on polyether urethane (PEUI) and styrene copolymer (S-co-AA (K+)) was studied by the method of spectral analysis in the far (70-420 cm) IR range. An analysis of the spectra of PEUI / S-co-AA (K+) composites showed that with an increase in the content of S-co-AA (K+), a new network of intermolecular (ion-molecular) bonds forms in the system. The appearance of an intense absorption band at ~ 180 cm, due to vibrations of K+ cations in the electrostatic region of anions (COO-) carboxyl groups, its significant half width and the presence of maxima at 145, 155, 177, 185, and 200 cm indicate the formation of various on the organization of forms of cation-anion associates in the system: from simple ion pairs to complex multiplets and clusters.

Fused bis-azacalixphyrin that reaches NIR-II absorptions

The fusion of two azacalixphyrins produces a new class of NIR-II dyes showing an intense absorption band in the 1000–1200 nm NIR range.

Propeller-Shaped Aluminum Complexes with an Azaperylene Core in the Ligands

Tris(8-hydroxyquinoline) aluminum(III) (Alq3) and its derivatives, characterized by a propeller-shaped three-dimensionally π-conjugated structure, have been intensively studied in the few past decades on account of their potential utility in optoelectronic applications. Reported herein are the synthesis and properties of π-extended Alq3 complexes that contain an azaperylene core in each ligand. Intramolecular palladium-catalyzed direct C–H arylations or base-promoted arylations were employed to prepare these large Alq3 analogues. A single-crystal X-ray diffraction analysis of one of the obtained Al complexes revealed a unique three-dimensional packing structure within the crystal, i.e., a honeycomb packing along the ab-plane and columnar π-stacks along the c-axis. An Alq3 analogue with azaperylene-dicarboximide ligands exhibited deep blue color in solution with an intense absorption band that extended to 780 nm (λmax = 634 nm; ε = 58,000 M−1 cm−1).

BF2 complexes of 1,3-diketones on the surface of phosphorus dendrimers: synthesis and study of the photoluminescence properties

Difluoroboron complexes of monomeric and dimeric diketones and of generations 0–4 of phosphorus dendrimers ended by diketone ligands are synthesized and characterized. Their photoluminescence properties are measured. All compounds exhibit an intense absorption band in the near UV region. Both model dimers and dendrimers show a marked hypsochromic shift of this absorption band compared with the monomeric difluoroboron complex. The fluorescence of the dioxaborine complex subunit in the multichromophoric dendritic architectures is quenched compared with the emission of the isolated monomeric fluorophore, presumably due to interactions between the terminal groups of dendrimers.

Synthesis of Mononuclear Non-Heme Iron(III)-Hydroperoxo Complex as an Oxidative Catalyst

Mononuclear FeII complex [FeII(ppba)]2+ (ppba = (6-pivalamido-2-pyridylmethyl) (2-pyridylmethyl)tert-butylamine) (1) has been synthesized and structurally characterized. The addition of H2O2 (10eq) to an acetone solution of 1 at -78°C generated FeIIIPPBA-OOH species, accompanied by a color change from pale yellow to reddish purple, which showed an intense absorption band corresponding to LMCT band (HOO- to Fe) at 528 nm (ε = 1120 M-1cm-1). The ESR spectrum for FeIIIPPBA-OOH species (g// = 4.22, g⊥ = 7.70 in acetone at 77 K) was typical of a high-spin FeIII species, suggesting that the FeIIIPPBA-OOH species is maintained as a mononuclear complex in the solution state. The resonance Raman spectra, when H2 16O2 and H2 18O2 were used, exhibited intense bands characteristic to the O-O stretching vibrations at 880 cm-1 ν(16O-16O) and 824 cm-1 ν(18O-18O), respectively. These findings suggest that FeIIIPPBA-OOH species is [FeIII(ppba)(OOH)]2+ (2). In order to understand the catalytic reactivity of complex 2, oxidative reactions for some organic substrates by complex 2 were carried out in the presence of H2O2; thioanisole was oxidized to the corresponding sulfoxide and sulfone, respectively, and furthermore, cyclohexene was converted to cyclohexene oxide, cyclohexenol and cyclohexenone.

Ultraviolet spectrum of domoic acid

The ultraviolet spectrum of aqueous domoic acid solutions has an intense absorption band, whose λmax shifts from 240.0 ± 0.3 nm at pH 1.3 to 244.7 ± 0.3 nm at pH 12.3. At the same time, its εmax increases from 24250 to 26700 L mol−1 cm−1. At pH 7 λmax is 242.8 ± 0.3 nm and εmax is 26035 ± 200 L mol−1 cm−1 Analysis of the variation of λmax and εmax with pH allowed us to estimate the values of these quantities for each of the five stages of protonation of domoic acid and to verify the pK values reported by Takemoto and Daigo. Keywords: ultraviolet spectrum, pK values, protonation, domoic acid.