Identification and characterization of chemically masked derivatives of pseudoephedrine, ephedrine, methamphetamine, and MDMA

Qualitative and quantitative analysis of chemical constituents in goupi plaster prepared by various extraction methods using UPLC-Q-Exactive-MS and UPLC-MS/MS

Goupi plaster, a representative preparation of black plaster, has demonstrated promising effects in treating knee osteoarthritis. However, high temperature used in traditional frying extraction may cause decomposition of its effective components, thus limiting the efficacy. This study aimed to explore the scientific nature of the traditional preparation technology of Goupi plaster, and to compare the effects of different extraction methods on the types of chemical components and the content of index components. The UPLC-Q-Exactive-MS and UPLC-MS/MS technologies which have high efficiency, sensitivity and accuracy, were used to qualitatively and quantitatively analyze the chemical components of Goupi plaster under different preparation processes. The results show that the extraction solvent approach is different from the traditional frying extraction method, and has a positive effect. However, the mechanism of action of Goupi plaster is complex and its pharmacological effects are diverse. Future studies should explore whether it necessary to change the frying extraction method. This experiment provides a theoretical basis that will guide further scientific discussion and research into the frying extraction of Goupi plaster.

Changes in methamphetamine impurity profiles induced by tert-butoxycarbonylation

Analysis of impurities in methamphetamine (MA) can be used to characterize MA seizures, investigate the relationship among MA seizures, and provide information on their synthetic routes. Recently, chemically derivatized MA, such as tert-butoxycarbonyl (t-Boc) MA, has been seized and attracted attention because routine forensic analysis methods may fail to correctly identify them. Chemical derivatization is a simple method for protection and deprotection of a compound, and protection of MA using t-Boc can be used to mask the MA. Although t-Boc derivatization might alter the impurity profile of MA, the actual changes in the impurity profile have not been investigated. In this study, changes in the MA impurity profile with tert-butoxycarbonylation were explored. MA and some typical impurities were derivatized using di-tert-butyl dicarbonate and water. Analysis of the impurities in five MA samples by gas chromatography showed that peaks both appeared and disappeared for the deprotected MA compared with the original MA. However, typical impurities important for characterizing MA seizures were conserved after derivatization and deprotection. Most of the new peaks were speculated to be contaminants introduced during derivatization and deprotection. A peak giving a mass spectrum similar to that of t-Boc MA was detected in the chromatograms of t-Boc MA and deprotected MA. Although the origin of this peak was not determined, it might be a marker for the MA involving tert-butoxycarbonylation. These results indicate that tert-butoxycarbonylation can alter the MA impurity profile; therefore, care is needed when interpreting results for derivatized MA.

N,N-Diformylmescaline: A novel analogue of mescaline detected in Queensland

N,N-Diformylmescaline, a novel analogue of mescaline, has recently been detected in Australia in two unrelated seizures. To confirm the identification, a three-step synthesis from 3,4,5-trimethoxyphenylacetic acid was devised. However, purification of the final product proved problematic with the compound prone to degradation in solution. Analysis of the compound by LC-MS indicated that the compound was unstable under acidic and basic conditions, breaking down to N-formylmescaline. Further degradation to mescaline was observed when the compound was dissolved in hydrochloric acid for an extended period of time suggesting that N,N-diformylmescaline may be a prodrug for mescaline. The GC-MS, NMR and FTIR data for the seized compound are presented along with details of the synthesis and studies of the compound's stability in solution.