Chemical Composition of the Bark of Tetrapterys mucronata and Identification of Acetylcholinesterase Inhibitory Constituents

Abstract

The secondary metabolite content of Tetrapterys mucronata, a poorly studied plant that is used occasionally in Brazil for the preparation of a psychotropic plant decoction called "Ayahuasca", was determined to establish its chemical composition and to search for acetylcholinesterase (AChE) inhibitors. The ethanolic extract of the bark of T. mucronata exhibited in vitro AChE inhibition in a TLC bioautography assay. To localize the active compounds, biological profiling for AChE inhibition was performed using at-line HPLC-microfractionation in 96-well plates and subsequent AChE inhibition bioautography. The analytical HPLC-PDA conditions were transferred geometrically to a preparative medium-pressure liquid chromatography column using chromatographic calculations for the efficient isolation of the active compounds at the milligram scale. Twenty-two compounds were isolated, of which six are new natural products. The structures of the new compounds (9, 10, 16-18, and 20) were elucidated by spectroscopic data interpretation. Compounds 1, 5, 6, 9, and 10 inhibited AChE with IC50 values below 15 μM.

LC-MS/MS Quantitative Determination of Tetrapterys mucronata Alkaloids, a Plant Occasionally used in Ayahuasca Preparation

“…(Malpighiaceae) (Schultes and Hofmann, ; Ott, ;). In a previous extensive phytochemical investigation on this plant, 22 metabolites were identified belonging to lignans, phenanthrene derivatives, aliphatic amides, dimeric indole alkaloids and tryptamine derivatives (Queiroz et al , ). Among these compounds the presence of bufotenine ( 1 ), 5‐methoxy‐ N ‐methyltryptamine ( 2 ), 5‐methoxy‐bufotenine ( 3 ) and 2‐methyl‐6‐methoxy‐1,2,3,4‐tetrahydro‐β‐carboline ( 4 ) was unexpected because such alkaloids are uncommon in ayahuasca (Fig.…”

Antifungals and acetylcholinesterase inhibitors from the stem bark of Croton heliotropiifolius

“…In the frame of our continuous search for antifungal and acetylcholinesterase inhibitors from natural origin (Favre-Godal et al, 2014;Queiroz et al, 2014), the ethanolic extract of the stem bark of C. heliotropiifolius demonstrated significant activities in both assays. To our knowledge, no thorough phytochemical investigation has been performed on this plant and this study presents the isolation and structure elucidation of the bioactive compounds.…”

Acetylcholinesterase inhibitory dimeric indole derivatives from the marine actinomycetes Rubrobacter radiotolerans

“…Chemical investigation of the crude extract uncovered indole derivatives representing similar carbon skeletons with reported mocronatin A which was isolated from the bark of Tetrapterys mucronata [7]. They are presumably biogenetically related to the condensation reaction between two tryptophans.…”

“…Indole derivatives derived from marine invertebrates exhibit diverse and potent bioactivities, such as antioxidant; PLA2 (phospholipase A2) inhibition activity; antimicrobial activity; anti-angiogenic effect; anti-inflammtory, PPAR-γ agnostic, cytotoxicity, the reported compound mucronatin A, which shared the same carbon skeleton, exhibited moderate AchE inhibitory activity [7,[11][12][13][14][15][16]. Hence, in our search for the biological activities of isolated compounds, the cytotoxicity, and AchE inhibitory A C C E P T E D M A N U S C R I P T…”