Bicuculline

C. nobilis Pers. Bicuculline, corlumine, d-isocorypalmine, cory-... 

C. sibirica Pers. Bicuculline, cheilanthifoline, corlmnine, cryptcqjine,... 

D. chrysaniha Walp. Bicuculline, chrycentrine, cryptocavine, cryptopine, protopine. Base F 25, Ci3Hi40g(NMe), m.p. 230°, phenolic and lactonic. ... 

D. cucullaria (L) Bernh. Bicuculline, corlumine, cryptopine, a-aZZocryptopine, cularidine, cularine, ochotensine, protopine. Manske was unable to confirm from his specimen the presence of cucullarine recorded by Black et al. ... 

Bicuculline, C2oHi,06N. (Items 1, 9, 10, 13, 14, 18, 20, 23-26, 34, 35, 38 list, p. 169). This alkaloid exists in two forms, m.p. 177° and m.p. 196°, and has [a], ° + 130- 5° (CHCI3). The hydrochloride has m.p. 259° (dec.) and from the methiodide, W-methylbicuculline, plates, m.p. 246°, has been prepared. Bicuculline contains no methoxyl groups it behaves as a lactone and is convertible by alkalis into bicucine, which is possibly the corresponding hydroxy-aeid (see below). It simulates hydrastine in its reactions and differs from that base by CH, indicating that a methylene-dioxy group replaces two methoxyl groups, and this view is supported by comparison of the products of oxidative hydrolysis of the two alkaloids. Both yield hydrastinine (p. 163) as the basic product, but while hydrastine provides as the second product, opianic acid,... 

Bicucine, C20H19O7N, H2O. This alkaloid has m.. 222° (dec.) and — 115 4° (N/10, KHO) but in N/HCl it shows mutarotation — 145° to — 100°,due to the formation of an equilibrium mixture of bicucine and bicuculline. Alkaline permanganate oxidises it to 3 4-methylene-dioxyphthalic acid, isolated as the ethylimide. In view of its formation from bicuculline by the action of alkali, Manske has suggested for its formula (II) or (III), the former representing it as the nomarceine (p. 208) analogue of bicuculline, whilst (III) makes it the hydroxy-acid corresponding to the lactone, bicuculline and is preferred. 

Adlumine and Adlumidine. (Items 1, 21, 24, 25, 29 list, p. 169). From Adlumia cirrhosa Rap. Schlotterbeck isolated two alkaloids, adlumine, C3,H3 09N(0H)(0Me)2, m.p. 188, [ ]d + 39-88°, and adlumidine, C30H29O9N, m.p. 234°. Manske used these two names for alkaloids isolated from A. fungosa Greene, stated to be identical with A. cirrhosa Rap., and suggested (I) that Schlotterbeck s adlumine was probably bicuculline with some adlumine and (II) that the two adlumidines are identical. 

Synthesis of bicuculline and nitroadlumine. Groenewoud and Robinson synthesised bicuculline by the general method devised by Hope and Robinson, the initial products in this case being 6-nitro-3 4-methylene-dioxyphthalide (IV) prepared by a new method from normeconin, and hydrastinine (V). The condensation produet, called nitro-a -bicuculline (the X indicating that the dZ-product eannot yet be allocated to the a- or )3-stereoisomeric series cf. synthesis of hydrastine, p. 167), forms minute yellow needles, sinters at 176° and decomposes at 179°. It was reduced to amino-a -bicuculline (I R = NHj), yellow prisms, m.p. 208—4°, the latter... 

Bicuculline is a competitive antagonist at the GABAa receptor. It is a plant alkaloid. 

GABA GABAa (LGIC) t Cl" conductance Muscimol Bicuculline... 

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