Acetogenins from Annonaceae
In 1982, Jolad et al. isolated uvaricin, a new antitumor agent, from the roots of Uvaria acuminata (Annonaceae), a bis-tetrahydrofuranoid fatty acid lactone (1) related to polyketides or acetogenins. However, it contained a number of original structural c
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I. Introduction .
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II. Classification . . ........ . Synonyms of acetogenins . . . .. Listing (structures and physical data) . . . . . . . . . Distribution ..
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III. Extraction and isolation .
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IV. Structure elucidation ..
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V. Biogenetic hypotheses .
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VI. Syntheses . . . . . . .
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VII. Biological activities.
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Acknowledgements.
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References .
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I. Introduction In 1982, JOLAD et al. isolated uvaricin, a new antitumor agent, from the roots of Uvaria acuminata (Annonaceae), a bis-tetrahydrofuranoid fatty acid lactone (1) related to polyketides or acetogenins. However, it contained a number of original structural characteristics, particularly a linear
W. Herz et al. (eds.), Fortschritte der Chemie organischer Naturstoffe Progress in the Chemistry of Organic Natural Products © Springer-Verlag/Wien 1997
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A. CAVE et al.
acetogenin, a bis-tetrahydrofuran pattern flanked by hydroxyls and a terminal unsaturated lactone. Two years later, DABRAH and SNEDEN (2, 3) and CORTES et al. (4) described four new products presenting the same structural characteristics. Because these products formed a new class of natural compounds, and are only found in species belonging to the family of Annonaceae, they are commonly called acetogenins from Annonaceae. Annonaceous acetogenins constitute a series of C-35/C-37 natural products of polyketide origin derived from fatty acids. Their structure is characterized by a long alkyl chain bearing a terminal unsaturated ymethyl-y-lactone (sometimes rearranged to a y-lactone containing an acetonyl r:t. to the lactone carbonyl), one, two or three tetrahydrofuran rings and some oxygenated substituents along the chain, particularly r:t. to a tetrahydrofuran, and in some cases double bonds and/or epoxides. 00
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Because the acetogenins from Annonaceae exhibit a broad range of potential biological properties such as cytotoxic, antitumoral, antiparasitic, pesticidal, antimicrobial and immunosuppresive activities, research in the field expanded greatly with the number of isolated and reported acetogenins increasing rapidly. 31 acetogenins were described in 1990 (5) and 61 in 1993 (6) as part of two reviews, and they now number more than 160. At the same time, numerous synthetic studies were initiated by an evergrowing number of research teams, leading to a rapid increase in the number of papers dealing with isolation, structural elucidation, synthesis and biology. Between 1982 and 1992, about 80 papers appeared, and since 1993 they have reached about 130.
II. Classification Acetogenins from Annonaceae can be classified into four main types according to the number and arrangement of the tetrahydrofuran rings along the alkyl chain. Type A with one tetrahydrofuran nucleus. In most of the acetogenins of type A the tetrahydrofuran is flanked by two hydroxyls at the r:t. and r:t.' positions. References, pp. 273-288
Acetogenins from Annonaceae
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Type B with two adjacent tetrahydrofurans. To date, four acetogenins of type B do not contain hydroxylrx of the
