219700-40-0Relevant academic research and scientific papers
Enantioselective synthesis of tussilagine and isotussilagine
Ma, Dawei,Zhang, Jianhua
, p. 9067 - 9068 (1998)
Tussilagine and isotussilagine are synthesized through the coupling reactions of N,N-disubstituted β-amino-esters with methyl pyruvate and Mitsunobu reactions as key steps.
β-Amino ester route to tussilagine, isotussilagine and (-)-petasinecine
Ma, Dawei,Zhang, Jianhua
, p. 1703 - 1707 (2007/10/03)
Condensation of enantiopure β-amino ester 2a with methyl pyruvate provides two diastereoisomers 3 and 4. Both 3 and 4 are subjected to hydrogenation followed by cyclization producing pyrrolidinones 5 and 8. From 5 and 8 isotussilagine and tussilagine are obtained respectively, by using a Mitsunobu reaction as a key step. In a similar manner, (-)-petasinecine is synthesized from the condensation product of 2b with ethyl glyoxalate.
Sulfanyl radical mediated cyclization of aminyl radicals
Montevecchi, Pier Carlo,Navacchia, Maria Luisa
, p. 9077 - 9080 (2007/10/03)
1-(2-aminophenyl)pent-1-yne 1 reacted with benzenethiol at 150 °C under radical conditions to give the thiol/alkyne adduct 2, the benzothiophene 4 and the indole 5. Reaction of 1 with benzenesulfanyl radicals produced from diphenyl disulfide in the absence of hydrogen donors gave only the indole 5 in high yields. Formation of indole 5 was explained in terms of sulfanyl radical mediated aminyl radical cyclization onto the alkyne triple bond.
