Aporphines structure

After a short period (253, 437, 449, 494), during which argemonine was ascribed the aporphine structure, it was recognized (330, 515) on the basis of NMR-analyses (Table XI), that this alkaloid has a symmetrical molecule and consequently the skeletal structure which was reported earlier for pavine by Schopf (439) and then by Battersby (42). By degra-... 

Of several aporphines structurally related to apomorphine, 11-hydroxyaporphine has proven to be active upon oral administration to spontaneously hypertensive cats. That a catechol system is not an absolute requirement for dopaminergic activity was demonstrated by the finding that ( )-(43) and ( )-(44) show appreciable activity in rats. 

Canonica L, Galliani G, Lesma G, Tollari S (1981) Enzymatic transformations of alkaloids utilizing pure enzymes. Proc 1st Int Conf Chem Biotechnol Biol Act Nat Prod Istvol. 2 522-527 Cava MP, Bessho K (1966) Hernandia alkaloids II. Hernandaline, a new elaborated aporphine structural type. Tetrahedron Lett 36 4279-4282 Chen CR, Beal JL, Doskotch RW, Mitscher LA, Svoboda GH (1974) A phytochemical study of Doryphora sassafras II. Isolation of eleven crystalline alkaloids from the bark. Lloydia 37 493-500... 

Wu YC, Chen CH, Yang TH, et al. Cytotoxic aporphines from Artabotrys uncinatus and the structure and stereochemistry of artacinatine. Phytochemistry 1989 28 2191-2195. 

The second illustration above is a phthalide THIQ, and these phenethylamines are sometimes referred to as secophthalide-isoquinolines. Here, the oxygen atom of the original isofuranone ring is substituted on the newly formed double bond. This structure can easily open up to the corresponding ketonic carboxylic acid. These seco-modifications of the attacked isoquinoline (first example, illustrated with an aporphine) and the simpler 1-substituted isoquinolines (second example, as illustrated by the isobenzofuranone) are the only ones included in this book. The standard phenethylamines that are commonly found in cacti, compounds which are not from these seco-mecha-nisms, have been tabulated in TIHKAL and will not be repeated here. 

A minor constituent of P. somniferum is the aporphine alkaloid isoboldine (Figure 6.58). Other species of poppy, e.g. Papaver orientale and P. pseudoorientale, are known to synthesize aporphine alkaloids as principal constituents rather than morphinan structures. (Aj-Isoboldinc is readily appreciated to be the product of oxidative coupling of (5)-reticuline, coupling ortho to the phenol group in the tetrahydroisoquinoline, and para to the phenol of the benzyl substituent... 

Berberis actinacantha Mart, ex Schult. (Berberidaceae) furnished (+)-epiberbivaldine (475), C36H3gN206, amorphous, [ot] 5 +45.7° (c 0.12, CHC13). Epiberbivaldine is di-astereomeric to the known berbivaldine (89). Structure proof was by NOEDS and di-enone-phenol rearrangement to an aporphine-benzylisoquinoline dimer (556). 

Natalinine (491), C25H23N05, amorphous, is a minor alkaloid of Berberis empetrifolia Lam. MS and high-resolution NMR established the skeletal structure, and CD indicated the (R) configuration (561). Natalinine may be derived biogenetically from catabolism of an aporphine-benzylisoquinoline dimer [such as pakistanine (92), a major co-occurring alkaloid] (561), or by rearrangement of a coyhaiquine (107)-type dimer (562). 

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... 

Transformations of aporphines by microorganisms involving O- and N-demethylation (89, 92) and CH—CH dehydrogenation (92) have been reported. In a preliminary screening study, Wolters reported the metabolism of boldine and a related alkaloid of undisclosed structure to unidentified products by Piricularia oryzae (42). More detailed studies with a series of microorganisms have been carried out by Rosazza and co-workers (89, 92). 

Aporphinoids are by far the most abundant alkaloids in this genus and also, generally speaking, in the family Annonaceae. Guatteria has proved to be a rich source of unusual structures of this general type. Aporphines have been reviewed in Volume 24 of this treatise (3) and elsewhere (4-7), and a review on aporphinoids of the Annonaceae has just been published (8). For this reason we address the structures and chemistry of only a few alkaloids of this type that have not been included in the Kametani and Honda review (5). 

Isocalycinine (74) and discoguattine (75) are the only two aporphines of Guat-teria known to possess a 9,11-dioxygenated ring D, which had seemed to be a characteristic feature of Duguetia (Annonaceae) (67). Both alkaloids were isolated from G. discolor (24), and their structures were easily determined by the usual spectroscopic methods. In both, a meta-coupled AB system was the only outstanding feature recognizable in the H-NMR spectra which, however, had to be recorded in CSDSN to achieve adequate resolution and, in the case of isocalycinine (74), to confirm the location of the phenol function at C-9. 

A record number of new aporphine alkaloids, sixteen, has been isolated and characterized during the year under review. Even better methods for the synthesis of aporphines in high yields have been developed,1-3 and an interesting relationship between aporphines, morphinandienones, neoproaporphines, and spirinedienones has been pointed out.1 A novel and unusual alkaloid is eupolauramine (70), which is structurally related to the aristolactams but which incorporates an additional nitrogen atom in ring A.4... 

The year under review has witnessed the isolation and structural elucidation of no less than nine new aporphines, as well as of five aporphine-benzylisoquinoline dimers. Two of these five aporphine-benzylisoquinolines, namely kalashine and khyberine, are the first such dimers known to be substituted at C-l 1 of the aporphine moiety. Thallium(m) trifluoroacetate is an oxidizing agent which effects the cyclization of tetrahydrobenzylisoquinolines to aporphines in satisfactory yields.1 A listing of aporphinoid alkaloids has appeared.2... 

A full paper has appeared describing the synthesis of the aporphines (34) and (35) through treatment of the p-quinol acetate (33) with trifluoroacetic acid.46 The non-identity of (35) with natural lirinine confirmed structure (36) for lirinine. 

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