The increased interest in N,N-dialkyl tryptamines is a reflection of their diverse range of biologically active properties. Deuterated derivatives are of interest for use as internal standards in bioanalytical or pharmacological assays. The present study reports on the synthesis of twelve novel 5-ethoxy-N,N-dialkyl-[α,α,β,β-H(4) ]-tryptamines and their [α,α,β,β-D(4) ]-counterparts following the Speeter and Anthony procedure. The normally time-consuming reduction step was carried out in 5 min under microwave-accelerated conditions. Good yields were obtained using tetrahydrofuran as the solvent at 150 °C. The resulting 24 tryptamines have been characterized by 1D/2D nuclear magnetic resonance spectroscopy and gas chromatography ion trap mass spectrometry. Differential fragmentation of side-chain-related iminium ions has been observed as a key principle. Because many N,N-dialkyltryptamines are available outside of traditional pharmaceutical supply chains as so-called 'research chemicals', the availability, as standards, of these new N,N-dialkyltryptamines will aid in identifiying novel tryptamines arising from these other souces. They should therefore be of immediate value within forensic, research, and public health contexts.

The absence of reference material is a commonly experienced difficulty among medical and forensic professionals tasked with identifying new psychoactive substances that are encountered for the first time. The identification of newly emerging substances lies at the heart of forensic and clinical analysis, and a proactive public health policy calls for a thorough analysis of the properties of new psychoactive substances before they appear in the emergency clinic, where they may be noticed because of adverse reactions or toxicity. For example, a wide range of N,N-dialkyltryptamines show psychoactive properties in humans and these tryptamines are sometimes encountered as intoxicants. However, most of the existing reference data on new psychoactive tryptamines have been obtained retrospectively, after reports of acute toxicities. To address the need for reference standards for new tryptamines, thirteen 5-methoxy-2-methyl-N,N-dialkyltryptamines were prepared. Analytical characterization was based on ¹H and ¹³C nuclear magnetic resonance (NMR), gas chromatography-electron ionization ion-trap mass spectrometry (GC-EI-IT-MS) and chemical ionization-ion-trap tandem mass spectrometry (CI-IT-MS/MS), respectively. Differentiation among isomers was feasible by NMR and MS. In addition to the expected iminium ion base peak, indole-related key ions were detected under EI-IT-MS conditions at m/z 174, 159, 131, 130, and 103. CI-IT-MS/MS analysis of the 5-methoxy-2-methyl derivatives revealed the presence of m/z 188 in addition to [M+H]+ and the iminium species. This study served as an extension from previous work on isomeric 5-ethoxylated counterparts and confirmed the ability to differentiate between the two groups. The data provided here add to the existing body of literature and aim to serve both forensic and clinical communities.

The chemical investigation of the methanol extract of Hymenodictyon orixense bark, a Thai medicinal herb, provided five compounds. Their structures were identified on the basis of 1D NMR and MS data, as well as by comparison of the data with published values, as an iridoid glycoside: loganin (1), four coumarins: scopoletin (2), scopolin (3), hymexelsin (4) and scopoletin 7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (5). Compounds 1-5 showed acetylcholinesterase (AChE) inhibitory activity in the range of 13.92-34.18% at a concentration of 100 μg/mL. In addition, compounds 1 and 5 are reported for the first time from this genus.

Curcumin derivatives were successfully synthesized from 3,5-dimethylisoxazole by lateral metalation and condensation with various aromatic aldehydes sequentially at C 5 -and C 3 -methyl groups. After dehydration, further transformation of isoxazole ring to b-diketone moiety was accomplished by reductive ring opening using molybdenum hexacarbonyl [Mo(CO) 6 ] and subsequent simple acidic hydrolysis.