Oxoaporphines structure

Glaunine (67) and glaunidine (68) are two new oxoaporphines from Glaucium fimbrilligerum (Papaveraceae).47 Arosine, found in G. flavum Cr. var. vestitum, must be identical with glaunidine, while arosinine, from the same source, possesses structure (69).48 Oxidation of the aporphine corydine with iodine and... 

Oxoisocalycinine (106), which cooccurs with the ring D-9,11-dioxygenated isocalycinine (74) and discoguattine (75) in G. discolor (24), is the only example to date of an oxoaporphine with this unusual substitution pattern. The alternative oxocalycinine and oxoisocalycinine structures were suggested by mass and H-NMR spectra, which are quite unexceptional, and the actual positions of the substituents were established by zinc-hydrochloric acid reduction to isocalycinine (74) (24). 

Recently, Castedo et al. (137) studied enamide photocyclization for aporphine synthesis and modified Cava s procedure (135 -137) after consideration of the reaction course and structural requirement for the exclusive formation of aporphine. Castedo s group concluded that an enamide should have a forced m-stilbene geometry, in order to avoid an undesired mode of cyclization leading to protoberberine-type compounds and also to avoid a facile conversion to oxoaporphines after cyclization. 

An investigation of the alkaloidal content of the Australian Eupomatia laurina R. Br. (Eupomatiaceae), yielded a number of alkaloids, among which are the oxoaporphine liriodenine and the 7-hydroxynoraporphine norushinsunine. A new minor alkaloid from this source is eupolauridine (48) whose structure was proven conclusively by total synthesis (Scheme 6). ... 

The numbering of the aporphine ring in the following alkaloids (aporphines, dehydroaporphines, oxoaporphines) is according to accepted practice [1,102-106], and is illustrated in the structure of acutifolidine (40). 

Azafluorenone and diazafluoranthene alkaloids, which are biogenetically related to oxoaporphines, usually co-occur in plants of the family Annona-ceae. Cyathocaline (53), C14H11NO4, mp 222-224°, is a new azafluorenone alkaloid isolated from the stem bark of Cyathocalyx zeylanica Champ, ex Hook. f. and Thoms., a species of the Annonaceae endemic to Sri Lanka (50). Its structure was elucidated using spectroscopic techniques and by... 

About a year after these findings, an orange-colored oxoaporphine was obtained from Stephania abyssinica Walp. (Menispermaceae) it was at first believed that this compound was not lanuginosine since the NMR spectrum, appeared to be different (33). The structure of the 8. abyssinica base was proved conclusively to correspond to 1,2-methylene-dioxy-9-methoxyoxoaporphine not only by a detailed analysis of its NMR spectrum, but also through its reduction with zinc in hydrochloric acid to (+ )-xylopine, i.e., ( + )-l,2-methylenedioxy-9-methoxy-noraporphine, which was further acetylated to ( )-A-acetylxylopine... 

The oxoaporphine alkaloids have been the subject of a recent review. Table 4 presents new isolation and structural elucidation studies of this class of alkaloids. 

Splendidine (37), a new oxoaporphine, has been obtained from Abuta rufescens Aublet ( = A. splendida) (Menispermaceae). Following its structural elucidation, its total synthesis was achieved via a Reissert-Pschorr sequence The known phenolic oxoaporphine subsessiline, found in a Guatteria species (Annonaceae), has been established to possess structure (39) instead of the... 

Killmer, L., Vogt, F. G., Freyer, A. J., Menachery, M. D. Adelman, C. M. (2003). Lakshminine, a New Rare Oxoisoaporphine Alkaloid from Sciadotenia toxifera, and Structural Revisions of Telazoline and Teladiazoline, Two Related Oxoaporphines from Telitoxicum peruvianum and T. glaziovii. J. Nat. Prod., 66, 115-118. 

Pontevedrine, which was originally believed to be a C-7 oxoaporphine derivative, has now been shown to possess a C-4,5-dioxoaporphine structure (see Sec. 16.2). The green alkaloid glauvine, found in Glaucium spp. (Papa-veraceae), is identical with corunnine. ... 

Sixty-eight oxoaporphines were isolated from various Annonaceous plants, liriodenine (XI. 18) being ubiquitous. From the structural point of view, these oxoaporphines are rarely substituted at positions 4, 5, 8, and 11. 

Most remarkable is the callus culture of Stephania cepharantha (Menispermaceae). Not only is it able to produce oxoaporphine alkaloids (Akasu et al. 1975) and bisben-zylisoquinolines (Akasu et al. 1976) but also two aristololactams which are only found in traces in the differentiated plants and are discussed as a hint for a possible systematic crosslink from the Menispermaceae to the Aristolochiaceae (Akasu et al. 1974). A further good example of the structure variability that can be produced by one culture is Fumaria capreolata (Fumariaceae) cultivated in our laboratory. Many structural types from a simple isoquinoline to a rather complicated structure like... 

The first TROPOL was imerubrine, isolated by Cava et al. from Abuta imene (38). In that paper, the chemical structure was erroneously assigned as an oxoaporphine. Later when the same authors isolated a second TROPOL (grandirubrine) from Abuta grandiflora (39), this new type of alkaloid was established. 

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