Alkaloids benzylisoquinolines

At least SO genera including some 7S species are known to be alkaloidal benzylisoquinolines, aporphines, berberines, and a variety of other N-containing compounds arc found throughout the family. Recent reviews of some of these constituents are available (Cave et al., 1989 Waterman, 1985 Zhong and Xie, 1988). The following record of positive alkaloid tests was obtained from 240 samples comprising 155 species. [Pg.15]

Keywords alkaloid biosynthesis alkaloid genes nicotine tropane alkaloids pyrrolizidine alkaloids benzylisoquinoline alkaloids monoterpene indole alkaloids ergot alkaloids acridone alkaloids purine alkaloids taxol betalains... [Pg.20]

A/ illNoronono alkaloids Benzylisoquinoline alkaloids p-carbollno alkaloids Cyclopeptide alkaloids Dilerpene alkaloids DIscorhabdin alkaloids Ergot alkaloids Hasiibanano-lype alkaloids Imidazole alkaloids Indole alkaloids Indolo-diterpene alkaloids Indolocarbazole alkaloids Isoqninoline alkaloids Loline alkaloids... [Pg.321]

To date, biosynthetic pathway for four classes of plant alkaloids has been characterized to some extent the benzylisoquinoline, monoterpenoid indole, purine, and tropane alkaloids. Benzylisoquinoline alkaloids (BIAs) are derived from tyrosine and are comprised of 2,500 defined structures found mainly in the Papaveraceae, Ranunculaceae, Berberidaceae, and Menispermaceae [11]. First step of BIA biosynthesis begins with the stereoselective Pictet-Spengler condensation of dopamine and 4-hydroxyphenylacetaldehyde to form (5)-norcoclaurine. Subsequently, through a series of methylations and hydroxylations, (5)-norcoclaurine gets converted into (5)-reticuline, which is the pivotal intermediate for many pharmaceutically important BIAs formed further down in the pathway (i.e., downstream pathways) (Fig. 8.6) [3]. [Pg.220]

These more complex phenylalanine-derived alkaloids, benzylisoquinolines and others, are also found in ca. 40 families the exact number depends on how the various families are delimited. In about 12 of them the occurrence of the alkaloids is rare. The main distribution in the subclass Magnoliidae, Dictoyledons (Dahlgren 1980), is as follows ... [Pg.16]

Opium is the dried, powdered sap of the unripe seed pod of Papaver somniferum, a poppy plant indigenous to Asia minor. Theophrastus described its medical properties in the third century BC, but the Sumerians, ca BC 4000, probably perceived its utility. Arab physicians knew of the dmg, and Arab traders carried it to the Orient where it was used as a treatment for dysentery. Paracelsus is credited with repopularizing the dmg in western Europe in the early sixteenth century by formulating opium into "laudanum", which is still in use. More than 20 different alkaloids (qv) of two different classes comprise 25% of the weight of dry opium. The benzylisoquinolines, characterized by papaverine [58-74-2] (1.0%), a smooth muscle relaxant, and noscapine [128-62-1] (6.0%), an antitussive agent, do not have any analgesic effects. The phenanthrenes, the second group, are the more common and include 10% morphine (1, = R = H), 0.5% codeine [76-57-3], C gH2 N03, (1, R = H, R = CH3), and 0.2 thebaine [115-37-7], C 2H2 N03, (2). [Pg.381]

Benzylamine, o-chloro-N-(cyanomethyl)-N-methyl-isoindole synthesis from, 4, 323 Benzylisoquinoline alkaloids synthesis, 1, 446 Benzynes... [Pg.567]

This example demonstrates how widely chemical profiles can differ between two populations separated by only a matter of kilometers in this case, populations of halictrum minus L. in the Voj vodina area of Serbia (Popovic et al., 1992) (Fig. 2.20). Plants collected at 500 m in the Fruska Gora Mountains (Novi Sad) afforded a comparatively complex mixture of benzylisoquinoline alkaloids that consisted of... [Pg.38]

Kwan CY, Achike FI (2002) Tetrandrine and related bis-benzylisoquinoline alkaloids from medicinal herbs cardiovascular effects and mechanisms of action. Acta Pharmacol Sin 23(12) 1057-1068... [Pg.94]

Scheme 2 Structures of the benzylisoquinoline alkaloid laudanosine and its transformed products (2, 3, and 4) by utilizing Pseudomonas putida incubated at 30 °C for 96 h [47]... [Pg.112]

Benzylisoquinoline alkaloids Leaves Anisocycla jollyana SiOj, AI2O3 Multicomponent eluent — — 13... [Pg.260]

C-9, and C-10, always with a phenolic hydroxy group at the 8a position. Moreover, they differ from one another by the oxidation state of the benzylic C-13 as well as by substitution and degree of saturation of the isoquinoline fragment. These alkaloids, classified as benzylisoquinoline alkaloids (2,70-74), have recently been called by Shamma et al. (75-77) pseudobenzyliso-quinolines originating from protoberberine alkaloids. In Table V a list of 8,8a-secoberbine alkaloids, sources, and spectral data are presented. [Pg.257]

The above syntheses were preceded by model investigations (143), as a result of which several unnatural 1,2-secoisoquinolines, e.g., 175-177 were synthesized (Scheme 30). Finally, a reaction reported by Bentley and Murray (144) is worth mentioning since it may serve as a model for biosynthetic conversion of benzylisoquinoline alkaloids to the seco analogs (Scheme 30). Heating of ketolaudanosine (174) with methyliodide unexpectedly formed a seco derivative 175 along with to the quaternary salt. By all probability it arose from the methiodide of 174 by air oxidation followed by ring opening. [Pg.284]

The following secodimeric alkaloids have been isolated from natural sources (+)-hernandaline (197), from Hernandia ovigera L. (158), (—)-natalinine (198) (759), and (+)-coyhaiquine (199) (160), the two latter from Berberis empetrifolia Lam. with the yields 0.00005 and 0.00008%, respectively. Appropriate aporphine-benzylisoquinoline or proaporphine-benzylisoqui-noline dimers are probably precursors of these seco alkaloids, although... [Pg.292]

This benzylisoquinoline alkaloid inhibits in vitro the specific bonding of [3H] dopamine to dopamine receptors and abrogates amphetamine-induced circling behavior in rodents with unilateral degeneration of dopaminergic neurons in the corpus striatum (109). [Pg.144]

The photocyclization of enamides has been widely employed in the construction of heterocyclic systems the N-acryloyl-2-aminopyridines 37, for example, are converted on irradiation to the lactams 38.36 Numerous benzylisoquinoline alkaloids have been prepared using this approach, and in particular, the syntheses of benzo[c]phenanthridine alkaloids have been reviewed.37 Thus, irradiation of the [Z]-l-ethylidene-2-benzoyltetra-hydroisoquinoline 39 affords the corresponding 8-oxoberberine 4038 competing photoisomerization to the E-isomer is observed but cyclization occurs only via the Z-isomer. Examples of syntheses of Amaryllidaceae and indole alkaloids have also been reported. In this way, the precursor 41 of ( )-lycoran has been obtained by oxidative cyclization of the enamide 42.39... [Pg.246]

PAULI, H.H., KUTCHAN, T.M., Molecular cloning and functional heterologous expression of two alleles encoding (5)-Y-methylcoclaurine 3 -hydroxylase (CYP80B1), a new methyl jasmonate-inducible cytochrome P-450-dependent monooxygenase of benzylisoquinoline alkaloid biosynthesis, Plant J., 1998,13, 793-801. [Pg.177]

Whereas the Annonaceae are characterized primarily by benzylisoquinoline alkaloids, two pyrrolidine alkaloids have recently been found in species belonging to this family. Squamolone (29) was isolated from Annona squamosa L. by Chinese workers in 1962 (68). Despite careful spectroscopic investigation and a total synthesis (Eq. 1), squamolone was assigned the incorrect diazepine formula 30. The correct structural formula (29) was later established by an unambiguous synthesis of 30 (Eq. 2). Compounds 29 and 30 proved to have very similar spectroscopic properties, which could justify the early confusion (69). [Pg.289]

Corydalis is a genus of the family Fumariaceae that is represented by some 320 species growing in the temperate climates of the northern hemisphere. Corydalis pallida Pers. var. tenuis from Japan was simultaneously examined for alkaloids by two groups of investigators (88, 89). Besides benzylisoquinoline-type alkaloids, rra/w-3-ethylidene-2-pyrrolidone (50) (alkaloid P) was present. The alternative formula 51 was ruled out by the nonidentity of the hydrogenation product of 50 with an authentic sample of 5-ethyl-2-pyrrolidone (52). Alkaloid... [Pg.293]

These transformation reactions are similar in part to those previously observed for laudanosine (201) and for the aporphine-benzylisoquinoline alkaloid thalicarpine (202). Laudanosine underwent regiospecific O-demethylation at... [Pg.385]

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