1061307-56-9Relevant articles and documents
Enantioselective Total Synthesis of (+)-Heilonine
Cassaidy, Kyle J.,Rawal, Viresh H.
, p. 16394 - 16400 (2021/10/20)
Chemical transformations that rapidly and efficiently construct a high level of molecular complexity in a single step are perhaps the most valuable in total synthesis. Among such transformations is the transition metal catalyzed [2 + 2 + 2] cycloisomerization reaction, which forges three new C-C bonds and one or more rings in a single synthetic operation. We report here a strategy that leverages this transformation to open de novo access to the Veratrum family of alkaloids. The highly convergent approach described herein includes (i) the enantioselective synthesis of a diyne fragment containing the steroidal A/B rings, (ii) the asymmetric synthesis of a propargyl-substituted piperidinone (F ring) unit, (iii) the high-yielding union of the above fragments, and (iv) the intramolecular [2 + 2 + 2] cycloisomerization reaction of the resulting carbon framework to construct in a single step the remaining three rings (C/D/E) of the hexacyclic cevanine skeleton. Efficient late-stage maneuvers culminated in the first total synthesis of heilonine (1), achieved in 21 steps starting from ethyl vinyl ketone.
Enantioselective synthesis of janus kinase inhibitor INCB018424 via an organocatalytic aza-michael reaction
Lin, Qiyan,Meloni, David,Pan, Yongchun,Xia, Michael,Rodgers, James,Shepard, Stacey,Li, Mei,Galya, Laurine,Metcalf, Brian,Yue, Tai-N,Liu, Pingli,Zhou, Jiacheng
supporting information; experimental part, p. 1999 - 2002 (2009/09/06)
An enantioselective synthesis of INCB018424 via organocatalytic asymmetric aza-Michael addition of pyrazoles (16 or 20) to (E)-3- cyclopentylacrylaldehyde (23) using diarylprolinol silyl ether as the catalyst was developed. Michael adducts (R)-24 and (R)-27 were isolated in good yield and high ee and were readily converted to INCB018424.
