ABSTRACT
The volatile and non-volatile constituents of the unripe fruits of Magnolia ovata (A. St.-Hil.) Spreng. (Magnoliaceae) were studied. The essential oils were obtained by hydrodistillation of the fruit of two plant populations (A and B) and analyzed by GC/FID and GC/MS. The oil of sample A was rich in sesquiterpenes, mainly spathulenol (19.3%), while the oil of sample B showed a predominance of aliphatic compounds, mainly hexadecanoic acid (52.0%). Extracts of the dried fruit contained fourteen known compounds including nine lignoids (magnovatin A, magnovatin B, acuminatin, licarin A, oleiferin A, oleiferin C, kadsurenin M, 4-O-demethylkadsurenim M and 7-epi-virolin), two sesquiterpene lactones (parthenolide and michelenolide) and three alkaloids (lysicamine, lanuginosine and O-methylmoschatoline). Michelenolide, 7-epi-virolin and lisycamine are reported for the first time in the species, while the remaining compounds have already been reported in the leaves and/or trunk bark o f Magnolia ovata. Acetylation o f oleiferin A yielded a ne wcompound, acetyl oleiferin A, whose NMR data and that of michelenolide are furnished.
Subject(s)
Fruit/chemistry , Magnolia/chemistry , Oils, Volatile/chemistry , Alkaloids/chemistry , Gas Chromatography-Mass Spectrometry , Lactones/chemistry , Magnetic Resonance Spectroscopy , Sesquiterpenes/chemistryABSTRACT
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.
