A new pentacyclic triterpene isolated from Myroxylon balsamum (syn. Myroxylon peruiferum)

Abstract

Um novo triterpeno pentacíclico, o 11α-metoxi-β-amirina (1) foi isolado de Myroxylon balsamum (L.) Harms (sin. Myroxylon peruiferum L.f.). A estrutura desta substância foi elucidada pela análise de seus dados de IV, EM, RMN 1 H e 13 C. RMN bidimensional foi também utilizada para definir a estrutura e atribuir os deslocamentos químicos dos átomos de hidrogênio e carbono do novo triterpeno.The new pentacyclic triterpene, 11α-methoxy-β-amyrin (1), was isolated from Myroxylon balsamum (L.) Harms (syn. Myroxylon peruiferum L.f.). Its structure was established on the basis of IR, MS, 1 H NMR, 13 C NMR. 2D NMR experiments were also used to establish the structure and the hydrogen and carbon chemical shift assignments of the new triterpene.

Chemical constituents from Aspidosperma illustre (Apocynaceae)

“…13,14 Confirmation of structure 10 was done by comparison with authentic sample of derivative monoacetate of triterpene 11-a-methoxy-β-amyrin isolated from Myroxylon balsamum (Fabaceae). 15 According to the literature, the triterpene 10 was also obtained as an intermediate reaction by allylic oxidation by N-bromosuccimide with β-amyrin acetate. 16 Thus, the pentacyclic isolated from Aspidosperma illustre was characterized as olean-12-ene-11a-methoxy-3β-acetate (10), a new natural product.…”

Fatty Acid Esters of Triterpenes from Erythroxylum passerinum

“…This statement is in agreement with the chemical shift of C-9 (δ 51.6) of the 11α-methoxy derivative. 8 The mass spectrum recorded for the transesterification product of 3 made it possible to recognize palmitic acid esterified at the C-3 position of the triterpene through the molecular ion at m/z 270 (methyl palmitate).…”

New ursane triterpenoids from Ficus pandurata and their binding affinity for human cannabinoid and opioid receptors

“…Furthermore, the correlations of H-11 with H-18, H 3 -25 and H 3 -26 and H-20 with H-18 and H 3 -28 suggested that these protons are on the other side of the molecule. On the basis of these findings and by comparison with the literature (Mahato and Kundu 1994; Mathias et al 2000), the structure of 11 was assigned as 1 β -hydroxy-3 β -ace-toxy-11 α -methoxy-urs-12-ene. To the best of our knowledge, 11 is a new triterpenoid, to which the name ficupanduratin A was given.…”

“…Its HMBC cross peak to C-11 established its placement at C-11. The relative stereochemistry at C-1, C-3 and C-11 was assigned based on the comparison of the 1 H and 13 C chemical shifts as well as the coupling constant values with those of related triterpenes; it was confirmed by the NOESY experiment (Topçu and Ulubelen 1999; Mathias et al 2000; Chiang and Kuo 2001; Mallavadhani et al 2006; Mohamed 2014). The NOESY cross peaks of H-1 to H-3, H-5 and H-9 as well as H-9 to 11-OCH 3 , H 3 -27 and H 3 -30 indicated that these protons were present on the same side of the molecule.…”