Tetranortriterpenoids and Dihydrocinnamic Acid Derivatives from Hortia colombiana

Abstract

Dois tetranortriterpenos, sendo um inédito e dois novos derivados do acido dihidrocinâmico foram obtidos da madeira de Hortia colombiana. Suas estruturas foram elucidadas por RMN, e as configurações relativas estabelecidas através de experimentos de nOe diferencial. Em adição, foram isolados aloxantoxiletina, nerolidol, epoxinerolidol, três conhecidos derivados do acido dihidrocinâmico e duas amidas.A novel tetranortriterpenoid and two dihydrocinnamic acid derivatives were obtained from the wood of Hortia colombiana. Their structures were elucidated by detailed NMR investigations and the relative configurations established by Difference NOE experiments. In addition, alloxanthoxyletin, nerolidol, epoxynerolidol, three known dihydrocinnamic acid derivatives and two amides were isolated. Detailed analysis of NMR data of Hortiolide A, whose structure was previosly established by X ray, are also provided.

T-Cadinol Nerolidol Ether from Schisandra Chinensis

“…The presence of the double bond in one of the fused rings results in partial planarity of the ring and the C-11' methyl group bisects the C-3 methylene protons, as suggested by the single chemical shift signal at δ 1.99 for these protons. The terpenes geraniol [6] and linalool [6] show similar chemical shifts to those observed in compound 1, hence confirming the assignments given in Table 1 for the extended hydrocarbon chain, which are exactly analogous to nerolidol [7] both in carbon and proton chemical shifts (Table 1), while those of the fused bicyclic ring compound are a complete match with those of Τ-cadinol [8] the structure shown in Figure 1, where axial ring protons 2', 1' 6', 7' 8', 9' at δ 1.38, 1.09, 1.96, 1.01, 1.33 and 1.41, respectively are alternating in a transconfigeration relative to each other. Compound 1 is thus an ether of Τ-cadinol and nerolidol, which, to the best of our knowledge, is a new compound.…”

Limonoids: Overview of Significant Bioactive Triterpenes Distributed in Plants Kingdom

“…Out of over 300 limonoids known to day, about one-third is accounted by neem (Azadirachta indica) and Chinaberry (Melia azedarach) alone. 1,[10][11][12] Citrus fruits and its closely related genera contain about 36 limonoid aglycones and 17 limonoid glucosides. 13) Citrus limonoids and their glucosides, the water-soluble triterpenoid compounds that occur naturally in citrus fruit and citrus juice in amounts comparable to vitamin C, can be reclaimed from citrus processing and citrus seeds as by-products in large quantities.…”

“…1). The structural variations of limonoids found in Rutaceae are less than in Meliaceae and are generally limited to the modification of A and B rings, the limonoids of Meliaceae are more complex with very high degree of oxidation and rearrangement exhibited in the parent limonoid structure 11,18) (Fig. 2).…”

“…Endo et al, 4) Bagge, 6) Waterman, 10) and Suarez et al 11) have illustrated the biosynthesis of limonoids showing that limonoids are synthesized via terpenoids biosynthetic pathway, starting with cyclization of squalene, which results into a tetracyclic ion (Fig. 3); euphane and tirucallane (Fig.…”

Occurrence, Biosynthesis, Biological activity and NMR Spectroscopy of D and B, D Ring Seco-limonoids of Meliaceae Family

“…Loss of C-16 by decarboxylation of the incipient β-keto acid in ring-D, followed by ketalization and a retro-aldol reaction to cleave the C-9 and C-10 bond account for most of the transformations necessary to obtain these compounds which are, therefore, heptanortriterpenoid derivatives. Two unusual limonoids, hortiolide A (114) and B (115) have been isolated from Hortia columbiana [101], in which the B-ring was modified into a five membered ring.…”