Two new indolic and quinolinic alkaloids and other secondary metabolites from Mostuea thomsonii (Loganiaceae)

Publication date: August 2018Source: Phytochemistry Letters, Volume 26Author(s): Eric Gustave Bobda Gompe, Blandine Marlyse Wache Ouahouo, Valerie Tedjon Sielinou, Maurice Tsaffack, Jean Fotie, Jules Clement Nguedia Assob, Hayato Ishikawa, Pierre Mkounga, Augustin Ephrem NkengfackAbstractPhytochemical investigation of the roots, stems and leaves of Mostuea thomsonii (Loganiaceae) resulted in the isolation of two new alkaloids of indolic and quinolinic types, named Thomsonines A (1) and B (2) respectively. Eleven additional known compounds, including one alkaloid namely camptothecine 3 and ten triterpene derivatives: 2α,3α,19α-trihydroxy-24-norurs-4(23),12-dien-28-oic acid 4, 3β-acetoxy-2α,19α-dihydroxy-24-norurs-4(23),12-dien-28-oic acid 5, oleanol 6, 3-O-ß-d-glucopyranosideolean-28-oic acid 7, 3-β-acetoxyoleanol 8, 2α, 3α, 19α-trihydroxy-24-nurs-4(23), 12-dien 9, 3-O-ß-d-glucopyranoside oleanane 10, friedelan-3-ol 11, 3-O-ß-d-glucopyranosylfriedelane 12 and decanol 13, have been isolated from the same sources. The structures of the new compounds were determined by detailed analyses of 1D and 2D NMR spectra, in combination with high-resolution mass spectrometry data and by direct comparison with related data from literature. Compounds 1–4 were evaluated in vitro for their antimicrobial activities against a wide range of micro-organisms using the broth micro-dilution technique, but none of them exhibited noticeable activity.Graphical abstract

Source: Phytochemistry Letters - July 6, 2018 Category: Chemistry Source Type: research