Conessin

Conessine C,iH,i(NMe)(NMej) norConessine, CjjH,gNj Conessimine, C,jHsi(NH)(NMea) woConessimine, C,iHaj(NMe)(NHiMe) Kurchine, CjaHjjNj Conimine, CjiH3j(NH)(NHMe) Conamine, Cj,H3i(NMe)(NHj) Conan himine, CaiH32(NH)(NH2)... 

Siddiqui et al have also investigated the nitration and the bromina-tion of conessine, and its oxidation by permanganate and by chromic acid, and have carried out various reactions with the products one outcome of this work is the suggestion that the structure of conessine includes the chain. CH CH. CHj. 

Addendum. In a recent paper Bertho et al. have described a new process for the isolation of kurchi alkaloids. From the final residue a new base, C23H34N2, m.p. 129 5°, was isolated as the carbonate, m.p. 91° it provides the following salts B, 2HI, 2H2O, dec.) 174° B, 2HCIO4, 2.5H2O, m.p. 283°, and a mono-acetyl derivative, m.p. 254°. In a second paper Bertho, Schonberger and Kaltenbom describe further products obtained in the oxidation of conessine by chromic acid and by potassium permanganate. ... 

Burn has pointed out that the grouping together of many properties as fundamentally the same, brings into some sort of order the long list of apparently pharmacologically unrelated alkaloids, and that the similarity in many properties of atropine, papaverine and quinine, and of conessine and quinine, suggests points of biochemical similarity. 

Olefins are also the products of hydroboratlon of enamines, followed by treatment of the organoborane products with hot acid (543,544). The reduction of enamines with sodium borohydride and acetic acid (545) and the selective reduction of dienamines with sodium borohydride to give homo-allylic tertiary amines (138-140,225,546,547), has been applied to the synthesis of conessine (548) and other aminosteroid analogs (545,549-552). Further examples of the reduction of imonium salts by sodium borohydride can be found in the reduction of Bischler-Napieralski products, and other cyclic imonium salts (102). 

The first few steps in a synthesis of the alkaloid conessine produce 9B, starting from 9A. Suggest a sequence of reactions for effecting this conversion. 

In order to illustrate what "the maximum correlation" and "the simplest possible solution" mean, we can compare the formation of ring A of the steroidal skeletons, in the synthesis of cortisone (8) by Sarett et al, accomplished in 1952 [28], with the synthesis of conessine (141 by Stork and his co-workers, accomplished ten years later, in 1962 [29] (Scheme 1.3). 

These two compounds have in common the presence of a polycyclic steroidal skeleton, and although in both syntheses the same strategy is used to build up ring A, the synthesis of cortisone shows a greater simplicity than the synthesis of conessine. 

By contrast, in the synthesis of conessine there is not such an efficient and elegant correlation among the different synthetic operations. Of course, we refer only to the construction of the A ring and do not mean to imply any demerit in Stork s synthesis of what is, after all, a more complex molecule. 

Therefore, nine steps or synthetic operations are necessary in the conessine synthesis for isomerising the cir-B/C decalin system to trans-hIC, a transformation that in the cortisone synthesis is accomplished without any extra step, since it takes place spontaneously in the oxidation step, which, in turn, is necessary to introduce the second angular methyl group and build up ring D of cortisone in a stereoselective manner. Better correlation amongst different synthetic operations would be difficult to find in more recent synthesis of similar complexity and magnitude than that of Sarett. 

It is certain that pancuronium is but the first of a series of steroids of this type There is l or example, need for an agent with its favourable properties but with the brevity ot action of suxamethonium. Achievement of this aim may not be too distant since quaternary derivatives of the alkaloid conessine, possessing (in cats at least) the required characteristics have recently been described [75], and dacuronium bromide is now under intensive study by the team responsible for the development of pancuronium. 

Saponins Steroid alkaloids Cholestane Conessine Cyclopamine Jervine Pregnenolone Protoveratrine A Protoveratrine B Solanidine Solasodine Squal amine Tomatidine... 

Apocynaceae Holarrhena floribunda Holarrhena antidysenterica Holaphyllamin Conessine... 

Communesin alkaloids 136 Communesin G 56, 136 Communesin H 56 Condaline 157 Condaline A 157 Conessine 10, 42 Coniceine 10... 

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