Protopines

Both hypecorine and corydalisol have been obtained by the reduction of the base (251), which is one product of the pyrolysis of protopine y-oxide (section 11). The base (252), structurally similar to hypecorine and hypecorinine, is a minor product of the photolytic oxidation of the alkaloid fumaricine (see section 13). 

6 -Hydroxymethyl 1audanosine, which is an analogue of mac-rantaline, gives the oxirane (253) on treatment with ethyl chloroformate, whereas macrantaline under the same conditions gives the stilbene (254) (S.Prior, W. Wiegrebe and G. Sariyar, Arch.Pharm. (Weinheim), 1982, 315, 273). 

A1locryptopine (256) has been obtained by the photo-oxidation of tetrahydroberberine methiodide (255) (Hanaoka et al., Pol. J.Chem., 1979, 79). 

A reverse transformation of the protopine system to an in-danobenzazepine is represented by the formation of the base (264) from 13-oxo-allocryptopine (265) by irradiation in t-butanol in the presence of potassium t-butoxide (Blasko et al., Chem.Comm., 1981, 1246). 

The pyrolysis of protopine iv-oxide has been shown to give, in addition to the examine (251), the normal product (266) of Cope degradation and the nitrogen-free cyclised product (267). Photolysis of the A -oxide gives the examine (251) and the benz-ophenanthridine alkaloid sanguinarine (268). Analogous prod- 

Protopine, cryptopine, and allocryptopine have been isolated from Papaver rupifragum,75 protopine and allocryptopine from Glaucium vitellinum,109 Corydalis ophiocarpa,71 and C. cava,70 and protopine from Nandina domestica110 and Thalictrum rugosum,12 

Allocryptopine has been prepared111 by the photolytic oxidation of tetra-hydroberberine methiodide its antiarrhythmic effects have been studied.112 

Protopine has been isolated from Bocconia frutescens,110 Fumaria judaica,111 F. schleicheri,112 and Papaver bracteatum,146 cryptopine from F. schleicheri,112 and allocryptopine from B. frutescens110 and Zanthoxylum nitidum.141 The protopine ring-system has been prepared from tetrahydrobenzindenoazepines (75) by photo-oxidation to the amides (76) followed by reduction with lithium aluminium hydride and re-oxidation with manganese dioxide.148-150 The tetrahydrobenzindenoazepines have been prepared from A-chloroacetyl-/ -phenylethylamines (73) by cyclization to the lactam (74) followed by reaction with a benzyl bromide and phosphorus oxychloride. -Protopine (77 R R2 — CH2)148 and fagarine II (77 R1 = R2 = Me)149 have been synthesized in this way. 

Orito and M. Itoh, Koen Yoshishu-Tennen Yuki Kagobutsu Toronkai 22nd, 1979, 562. 

Alkaloids of tnis sub-group have been isolated from the following Berberis darwinii protopine 

54 Berberis empetrifolia 90 Corydalis bulbosa protopine protopine 

Protopine and allocryptopine have been isolated from Papaver rhoeas, and protopine from Corydalis caua, C. gigantea, C. marschalliana, C. remota, C. rosea, and C. vaginans. The effect of protopine on induced cardiac arrhythmias has been studied.  

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Bocconia arborea Wats. Chelerythrine, aZZocryptopine, protopine ... 

Corydalis ambigua Cham, and Sch. Corybulbine, corydaline, dehydrocorydaline, protopine. Bases —(I). A quaternary chloride,... 

Daetylicapnos macrocapnos Hutchinson. aZZoCryptopine, protopine, Z- and dZ-stylopine. ... 

Dicentra canadensis Walp. Bulbocapnine, corydine, isocorydine, protopine. Base F 22, C3,H4oOiqN2, m.p. 237-8°, jdelds a quaternary chloride, C34H3oOgN2Cl(OMe)3, m.p. 286°. ... 

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. ... 

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