Atisine azomethine

Depending on the reaction time, treatment of atisine azomethine acetate (218) with ethylene oxide afforded either atisine acetate (219), atisine (4), or... 

A full report on the C n.m.r. studies of these and related compounds and a rebuttal of some of the previously published n.m.r. spectral interpretations (cf. this Report, 1978, Vol. 8, p. 238) have appeared. The rebuttal was submitted prior to the publication of the X-ray crystallographic studies. n.m.r. spectral data were reported for atisine (1), atisinone (68), isoatisine (66), isoatisinone (69), dihydroatisine (65), dihydroatisine diacetate (70), atidine (71), atidine diacetate (72), atisine azomethine (73), atisine azomethine acetate (74), atisine dihydro-azomethine (75), atisine A-methyl dihydro-azomethine (76), veatchine [(67a) and (67b)], garryine (77), dihydroveatchine (78), dihydroveatchine diacetate (79), veatchine azomethine (80), veatchine azomethine acetate (81), veatchine dihydro-azomethine (82), and veatchine X-methyl dihydro-azomethine (83). 

MW 299.2249 Atisine-/V,20-azomethine Azitine Cuauchichicine-N,20-azome thine Garryfoline-/V,20-azomethine Veatchine-N,20-azome thine C20H29NO... 

Definitive evidence on this point has been provided by Dvomik and Edwards (17), who have shown that hydration of the C2o-azomethine alcohol XXXIII derived from atisine (18, 19) gave the diol XXXIV, which on reduction, acetylation, selective hydrolysis, and oxidation gave a 7,8-secomethylketo acid (XXXV). Treatment of the latter with tri-fluoroacetyl peroxide followed by hydrolysis and dichromate oxidation gave the bis norketo acid XXXVI (1712, 1602 cm i). Dibromination of... 

The atisine and Garrya (35,36) alkaloids have been interrelated by converting both atisine (XXX) and veatchine, by a parallel sequence of degradations, to the same A-acetyl ester (XCV) (35, 36). The respective azomethine acetates (LXXXVII, LXXXVIII) derived from atisine (12,16-bond) and veatchine (13,16-bond) were converted to the A-acetyl derivatives (LXXXIX, XC) by reduction, acetylation, and saponification. Oxidation of LXXXIX and CX with permanganate/periodate under controlled conditions gave the respective carboxylic acids (XCIa,... 

The azomethine (CXIV) derived from atisine undergoes a reaction of further interest when refluxed with zinc dust in acetic anhydride (28). The major product is the 0,V-diacetate (CXVIII) together with 5-10% of a bimolecular product to which structure CXIX is assigned. Saponification of CXIX affords the corresponding alcohol (CXX). The linkage between the halves of CXIX is believed to be at C-19, because of the severely hindered environment about C-20. 

Masamune 104) has also converted compound CCCXII, obtained from veatchine azomethine acetate, by a multistep procedure to the monoester carboxylic acid CCLIII. Since the latter has already been converted to atisine by Pelletier and Parthasarathy 96) this work completes in a formal sense the synthesis of atisine also. 

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