55821-72-2

Upstream product

• 100060-48-8 7-aminomethyl-9-hydroxymethyl-quinolizin-4-one 
• 78867-61-5 3-benzyl-1,2,3,4,5,6-hexahydro-1,5-methano-pyrido[1,2-a][1,5]diazocin-8-one 
• 101351-46-6 3-cyano-6-oxo-6H-quinolizin-1,7-dicarboxylic acid diethyl ester 
• 100795-79-7 3-aminomethyl-6-oxo-6H-quinolizin-1-carboxylic acid ethyl ester 
• 52600-52-9 ethyl 5-cyano-6-hydroxy-2-methyl-pyridine-3-carboxylate 
• 64119-42-2 ethyl 6-chloro-5-cyano-2-methylnicotinate 
• 103038-00-2 ethyl 5-cyano-2-methylnicotinate 
• 321535-22-2 1'-benzyl-6-methoxy-1',4'-dihydro-[2,3']bipyridinyl-5'-carboxylic acid methyl ester 
• 321535-19-7 6-methoxy-[2,3']bipyridinyl-5'-carboxylic acid methyl ester 
• 321535-35-7 (6-methoxy-[2,3']bipyridinyl-5'-yl)-methanol 
• 40473-07-2 6-bromo-2-methoxypyridine 
• 29681-44-5 5-bromo-3-pyridine carboxylic acid methyl ester 

Downstream Products

• 807310-56-1 (+)-N-benzylcytisine 
• 485-35-8 cytisine 
• 78867-61-5 (1R,5S)-3-benzyl-1,2,3,4,5,6-hexahydro-8H-1,5-methanopyrido-[1,2-a][1,5]diazocin-8-one 
• 956928-49-7 (1S,5R)-3-{2-[(2-oxo-3-phenyl-2H-chromen-7-yl)oxy]ethyl}-1,2,3,4,5,6-hexahydro-8H-1,5-methanopyrido[1,2-a][1,5]diazocin-8-one 

Relevant academic research and scientific papers

Synthesis of (-)-Cytisine Using a 6- endo aza-Michael Addition

An asymmetric synthesis of (-)-cytisine has been achieved. The piperidine C-ring was formed using a stereodivergent intramolecular 6-endo aza-Michael addition. The B-ring was established by intramolecular pyridine N-alkylation. The absolute stereochemistry was established by an Evans acyl oxazolidinone enolate alkylation reaction that proceeded with an unexpected stereochemical outcome due to participation of the pyridine nitrogen lone pair.

Concise synthesis of (±)-cytisine via lithiation of N-Boc-bispidine

(Chemical Equation Presented) (±)-Cytisine has been synthesized in 19% overall yield via a six-step approach from commercially available materials. Key features of this new strategy are as follows: (i) initial construction of the bispidine core, (ii) lithiation-transmetalation-allylation of an N-Boc-bispidine, and (iii) a Pd/C-mediated dihydropyridone oxidation-N- debenzylation process.

Total synthesis of (±)-cytisine

(equation presented) The nicotine partial agonist cytisine was prepared in five steps featuring an "in situ" Stille or Suzuki biaryl pyridine coupling. Differentiation of the pyridyl rings was accomplished via selective benzylation and then reduction of a pyridinium ring. The penultimate diazabicyclo[3.3.1]-nonane intermediate was obtained with high diastereoselectivity. A similar sequence has been employed for the synthesis of novel derivative 9-methoxycytisine.

Total synthesis of (+/-)-cytisine via the intramolecular heck cyclization of activated N-alkyl glutarimides.

[reaction:see text] A synthesis of racemic cytisine 1 has been developed utilizing an intramolecular Heck cyclization to prepare the bridged tricyclic intermediate 2. The cyclization employs activated glutarimide-derived ketene aminals 3 (X = P(O)OEt(2) or SO(2)CF(3)) and represents the first use of such intermediates in metal-catalyzed processes.