Corydalis pallida

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... 

Relatively few new alkaloids have been isolated. Two groups have obtained trans-3-ethylidene-2-pyrrolidone ( alkaloid P ) (2) from Corydalis pallida var. tenuis.9,10 The structure was deduced from spectral data and by hydrogenation... 

The structure of imenine (72 R1 = R2 = OMe, R3 = R4 = Me, R5 = H), the first ketoaporphine alkaloid to have a substituent in the heterocyclic ring, was elucidated mainly by AT-ray analysis.92 The absolute configuration of S-( + )-isoboldine isolated from Corydalis pallida var. tenuis was assigned on the basis of o.r.d. and c.d. studies interestingly, all alkaloids isolated from this species belong to the S-series.97 The structure of the reduced proaporphine jaculadine... 

Capauridine and capaurimine were detected in redifferentiated plantlets of Corydalis pallida, whereas the alkaloids of callus tissues included none of the former and only small amounts of the latter alkaloid. (-)-Coptisine was isolated from seeds of Fumaria indica, the racemic form being a known constituent of the whole plant. "... 

From the plant Corydalis pallida Pers. var. tenuis Yatabe, trans-3-ethylidene-2-pyrrolidone (corydalactame) (alkaloid P) (209) was isolated and synthetically prepared (125, 130, 131). 

Comparatively few simple isoquinoline alkaloids have been found to occur naturally. Until now such compounds have been encountered in three or four species of the Cactaceae, in a Chenopodiaceae [Salsola arbuscula Pall. (S. richteri Karel)], in three species belonging to the family of the Fumari-aceae [Corydalis pallida (Thunb.) Pers.,C. awrea Willd., C. tvherosa DC.] and in one Papaveraceae Papaver somniferum L.). While no doubt exists as to the native occurrence of the anhalonium and salsola isoquinolines, hy-drohydrastinine and hydrocotarnine may have been artifacts from the benzylisoquinoline alkaloids of Corydalis tuberosa and Papaver somniferum. 

Corypalline was found by Manske (40) in Corydalis pallida and in the seeds of C. aurea. The base melts at 168° picrate, m.p. 178°. 

Sparteine (Chelidonium majus) (407) lrans-3-Ethylideno-2-pyrrolidone (= corydalac-tame) (Corydalis pallida var. tenuis) (408) Af-Methyltetrahydronorharmane (6-methoxy-2-methyl-1,2,3,4-tetrahydro- i-carboline)... 

Corydalis pallida Pers. Corydalis speciosa Maxim. Corydalis stricta Steph. ex DC. 

Horn JS, Paul AG, Rapoport H (1978) Biosynthetic conversion of thebaine to codeinone. Mechanism of ketone formation from enol ether in vivo. J Am Chem Soc 100 1895-1898 Kametani T, Ihara M, Honda T (1970) The alkaloids of Corydalis pallida var. tenuis (Yatabe) and the structures of pallidine and kikemanine. J Chem Soc (C) 1060—1064 Kirby GW, Massey SR, Steinreich P (1972) Biosynthesis of unnatural morphine derivatives in Papaver somniferum. J Chem Soc Perkin Trans 1 1642-1647 Kleinschmidt G, Mothes K (1959) Physiology and biosynthesis of alkaloids in Papaver somniferum. Z Naturforsch 14b 52-56... 

Fumaria capreolata (Tanahashi et al. unpublished) Corydalis incisa, Corydalis pallida, Dicentra peregrina, Eschscholtzia califomica, Papaver somniferum, P. seti-gerum, P. bracteatum, P. orientate, P. rhoeas (Ikuta et al. 1974)... 

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