Constituents of the Leaves of Magnolia ovata

Abstract

Two new lignans, magnovatins A (1) and B (2), along with nine known compounds, were isolated from the leaves of Magnolia ovata. The known compounds were identified as acuminatin (3), licarin A (4), kadsurenin M, 4-O-demethylkadsurenin M, oleiferin A, oleiferin C, spathulenol, parthenolide, and 11,13-dehydrocompressanolide. In addition, compounds 1 and 2 yielded four new derivatives (1a, 1b, 2a, and 2b). The structures of the new compounds were established on the basis of spectrometric data evaluation. Free-radical scavenging and antimicrobial activities of the major compunds 1, 3, and 4 were investigated.

Recent advances in research on lignans and neolignans

“…40 Neglignans B and F showed anti-HIV-1 activities with therapeutic index values greater than 50. Further phytochemical investigation of S. neglecta using RP-HPLC led to the isolation and characterization of neglectalignans A-D (91)(92)(93)(94), which showed moderate anti-HIV-1 activities with therapeutic index values above 62, 23, 58, and 28, respectively. 41 Neglschisandrins E (95) and F (96) were reported by Chen et al 18 as constituents of S. neglecta.…”

“…Magnovatins A (229) and B (230) are secondary metabolites from the leaves of Magnolia ovata (Magnoliaceae). 92 In order to determine the absolute conguration of these compounds, they were submitted to an acid-catalyzed cyclization, yielding the new lignans 229a and 230a, respectively. CD analysis of the products allowed deduction of the absolute congurations of the substrates given that C-7 undergoes inversion of conguration during the cyclization process (SN 2 mechanism).…”

Polycarpol in Unonopsis, Bocageopsis and Onychopetalum Amazonian species: chemosystematical implications and antimicrobial evaluation

“…The pure standard of polycarpol was evaluated for its antimicrobial activity using the broth microdilution method (96-well microtiter plates), as previously described (Salvador et al, 2002;Barros et al, 2009;Costa et al, 2010;Bataglion et al, 2014) to give concentrations between 10 and 500 g ml −1 . The minimal inhibitory concentration (MIC) was calculated as the lowest concentration showing complete inhibition of a tested strain.…”

Essential Oil and other Constituents from Magnolia Ovata Fruit

“…The oils were kept in a refrigerator at -4 °C until GC and GC/EIMS analysis were carried out as previously reported [4]. Spathulenol was confirmed by comparison with an authentic sample, previously isolated from M. ovata [10].…”