Oxyacanthine

Phenohc intermolecular coupling (46) of two laudanosoline (77, R = H) fragments, which may be preceded or followed by partial O- or N-methylation, gives rise to the dimeric or bisben2yhsoquinoline alkaloids such as oxyacanthine (79), obtained along with related materials from the roots... 

Berberine is probably the most widely distributed alkaloid. It and the allied alkaloids palmatine, jatrorrhizine, columbamine and coptisine occur somewhat frequently in the Rhcnadales (list, p. 169) as the tetrahydro-derivatives, but, in the botanical families referred to in the distribution list below, the tetrahydro-derivatives are exceptional and the unreduced alkaloids usual. The associated alkaloids include two members of the aporphine group, domesticine and t odomesticine (p. 315), one member of the cryptopine group, y-homochelidonine (p. 294) and two members of the double woquinoline type, viz., berbamine and oxyacanthine (p. 346). 

The following Berberis spp. contain mixtures of alkaloids — B. heteropoda Schrenk. Berberine, palmatine, jatrorrhizine, columbamine, berbamine and oxyacanthine. ... 

B. vulgaris L. Berberine, berberrubine, palmatine, jatrorrhizine, columbamine, berbamine, oxyacanthine and a base C19H22ON2, hydrochloride, m.p. 256°. 

Mahonia aquifolium Nutt. Berberis aquifolium Pursh.) Berberine, berbamine, oxyacanthine, a phenolic base, m.p. 190-3°, and undetermined alkaloids. 

There are now known a eonsiderable number of alkaloids containing two distinct woquinoline nuclei, such as emetine and its congeners (p. 394), and in the morphine sub-group, -morphine, dithebainone (p. 255), disinomenine and its pseudo-isomeride (p. 268). The most important collection of such alkaloids is the bisbenzylwoquinoline or biscoclaurine section of which the following two alkaloids, berbamine and oxyacanthine, are examples, but which is typically developed in the Menispermaceas. 

Oxyacanthine contains three methoxyl groups, and one phenolic hj droxyl group is indicated by the preparation of an 0-benzoyl derivative, a potassium derivative and a methyl ether (identical with trilobamine methyl ether, p. 357) yielding a hydroehloride,. 2HC1, m.p. 

Pharmacological Action. According to Curci, oxyacanthine in doses of 01 to 0-2 gm. produces in rabbits quick and laboured respiration, muscular tremors, clonic convulsions and cessation of respiration before the heart stops. Raymond-Hamet states that oxyacanthine hydrochloride in a dose of 10 mgm. injected into the femoral artery of a dog produced dilation of the blood vessels in the leg and general hypotension. 

Phaeanthine, C3JH42O0N2. (Item 8 list, p. 350.) This alkaloid was isolated by Santos.It has m.p. 210°, [a]u°° — 278° (CHCI3), yields a hydriodide, m.p. 268°, picrate, m.p. 263°, aurichloride, m.p. 170-1°, and a platinichloride, m.p. 280° (dec.), and contains four methoxyl and two methylimino groups. By the Hofmann degradation process it yields an optically inactive methine base A, m.p. 173°, which is oxidised by potassium permanganate in acetone to 2-methoxy-5 4 -dicarboxydiphenyl ether (p. 348). A comparison of the properties of phseanthine and tetrandrine by Kondo and Keimatsu indicates that these two alkaloids are optical antipodes, so that phseanthine will be represented by either (XXXIX) or (XL) as given on p. 348, 1 and of these two formula (R = Me) one must represent oxyacanthine methyl ether and the other berbamine methyl ether (centres of asymmetry d- and 1-) tetrandrine (centres of asymmetry both d-) and phseanthine (centres of asymmetry both 1-). 

When the methine base derived from trilobamine diethyl ether ethiodide is oxidised by permanganate it furnishes 2-ethoxydiphenyl ether 5 4 -dicarboxylie acid, identical with that (XXXIV p. 348, R = Et) similarly formed from oxyacanthine (p. 347) or dauricine (p. 353) and in the present case derived from the diphenyl ether residue represented by rings (1) and (2) in formula (A) or (B). This fixes the position of one hydroxyl group at OR in (A) or (B) the position of the second is still undetermined but it may well be OR in ring (3) of (A) or ring (4) of (B). ... 

Oxo processes, 13 768 17 725 for amyl alcohols, 2 770-771 described, 2 36-41 major producers using, 2 29-3 It for producing odd-numbered higher alcohols, 2 1, 10 5 215-217 Oxo reaction, in higher olefins, 17 712 Oxosuccinic acid, 23 419 Oxprenolol, molecular formula and structure, 5 156t Ox-Tran instruments, 3 402 Oxyacanthine, 2 88 Oxyacetylene flame, 1 221 Oxy acids... 

Albertisia papuana Aromoline, cocsoline, cocsuline, daphnoline, homoaromoline, isotrilobine, lindoldhamine, obaberine, oxyacanthine 72... 

B. lycium Aromoline, baluchistanamine, berbamine, berbamunine, isotetrandrine, oxyacanthine 181... 

Mahonia repens Obaberine, obamegine, oxyacanthine, thalrugosine 198... 

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