Dibenzocycloheptanoids from the Leaves of Cinnamomum subavenium

Abstract

Five dibenzocycloheptatrienes (1-3, 5, and 6) and one dibenzocycloheptadiene (8) together with 16 known compounds were isolated from the leaves of Cinnamomum subavenium. Application of HPLC-SPE-NMR to a selected fraction afforded two additional dibenzocycloheptatrienes (4, 7). The glycosides 2-7 comprise two diastereomers because of the chiral glycosyl moiety and the axial chirality of the biphenyl system. Their structures were elucidated via ECD and 2D NMR analyses and chemical degradation. Subavenosides D (5) and E (6) showed moderate inhibitory activity against α-glucosidase type IV from Bacillus stearothermophilus with IC₅₀ values of 50.7 and 19.0 μM, respectively.

Pharmacological properties and their medicinal uses of Cinnamomum: a review

“…Root 3,4-Methylenedioxy-5-methoxy cinnamyl alcohol; eugenol; isoobtusilactone A; myristicin; obtusilactone A, [255] subamol. [256] isoobtusilactone A, obtusilactone A, eugenol, myristicin, cinnamyl alcohol [255] Anticancer activity, [130,257] antiinflammatory, [130] antioxidant, [130,172,255] antityrosinase, [258] , enzyme inhibitory [259] Abdominal pain, chest pain, diarrhoea, hernia, nausea, rheumatism, stomach aches, swellings, vomiting [260] Stem (+)-Catechin, (+)-syringaresinol, (À)-epicatechin, (À)sesamin, ferulic acid, isolinderanolide B, linderanolide B6, p-hydroxybenzaldehyde, palmitic acid, secosubamolide, stearic acid, stigmasterol, stigmasteryl-D-glucoside, subamolides A-C, syringaldehyde, vanillic acid, vanillin, b-sitosterol, bsitosterol-D-glucoside [257] epicatechin; gibberellin; hydroxytyrosol; nine flavonoids, catechin; phloridzin; two tannins, cinnamtannins B-1 [259] Fatty acids: Hexadecanoic acid [262] Hydrocarbons: Cadalene; pentacosane; tridecane; acopaene; d-cadinene. [262] Others: (E)-Methyl cinnamate; (E)-a-ionone; (Z)isoeugenol; benzyl benzoate; cis-calamenene; cis-⍺bergamotene; cubenol; dodecene; elemol; geranyl acetate; geranyl formate; methyl eugenol; transpinocarveol; a-cubebene; a-cyperone.…”

“…[262] Others: (E)-Methyl cinnamate; (E)-a-ionone; (Z)isoeugenol; benzyl benzoate; cis-calamenene; cis-⍺bergamotene; cubenol; dodecene; elemol; geranyl acetate; geranyl formate; methyl eugenol; transpinocarveol; a-cubebene; a-cyperone. [262] cinnamtannins B-1 and D-1, [259] subamone [263] Terpinenes: (E)-Nerolidol; (E)-b-farnesene; 1,8-cineole; aristolone; borneol; camphene; cis-linalool oxide; geranial; geraniol; linalool; myrcene; neral; p-cymene; patchouli alcohol; spathulenol; terpinen-4-ol; translinalool oxide; viridiflorol; a-bisabolol; a-cadinol; ahumulene; a-muurolene; a-muurolol; a-pinene; aterpineol; b-bisabolene; b-caryophyllene; b-pinene; bselinene; c-muurolene; c-terpinene [262]…”

Total Synthesis of (±)‐Dihydroisosubamol

“…Although slow rotation around the biphenyl axis is possible at room temperature, giving rise to two conformers that should be spectroscopically distinguishable, due to the difference in energy of the two conformers only one single signal set was observed in 1 H and 13 C NMR. [2] This case was also described for the strongly related allocolchicines. [3] During the last years, gold-catalysed reactions have become a powerful tool in organic synthesis, [4] including the efficient synthesis of seven-membered ring systems.…”

Gold‐Catalyzed Hydrofunctionalizations and Spiroketalizations of Alkynes as Key Steps in Total Synthesis

“…The initially formed exo double bond subsequently isomerises under the reaction conditions and delivers 12 whereas no 8endo product was observed in any case. The methodology was applied for the syntheses of the dibenzocycloheptanoids (AE)dihydroisosubamol [22] and reticuol [23] To avoid a competing 6endo-dig cyclisation of the top aromatic ring, a chloro substituent was used as masked hydroxy group (Scheme 5). [24] In the intramolecular hydroheteroarylation of indoles with alkynes a remarkable dependence on the used gold catalyst is observed.…”