General Method for Synthesis of Erythrinan and Homoerythrinan Alkaloids (1): Synthesis of a Cycloerythrinan, as a Key Intermediate to Erythrina Alkaloids, by …

…, Y Niimura, K Takeda, T SANO, Y TSUDA

Index: Toda, Jun; Niimura, Yoshihiro; Takeda, Kaoru; Sano, Takehiro; Tsuda, Yoshisuke Chemical and Pharmaceutical Bulletin, 1998 , vol. 46, # 6 p. 906 - 912

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Citation Number: 24

Abstract

抄録 A new synthetic route to Erythrina alkaloids by formation of ring C utilizing a Pummerer- type intramolecular cyclization was developed. The N-(2-phenylthioethyl)-dioxopyrroline (3) was converted to 13 in five steps with satisfactory overall yield (69%) by means of [2+ 2] photocycloaddition followed by 1, 3-anionic rearrangement as crucial reactions. Treatment of the sulfoxide (13) with trifluoroacetic anhydride gave the cyclization product, 11- ...