913626-91-2Relevant academic research and scientific papers
Formal Synthesis of (+)-Lasubine II and (-)-Subcosine II via Organocatalytic Michael Addition of a Ketone to an α-Nitrostyrene
Moorthy,Dyapa, Rajendar,Pansare, Sunil V.
, p. 5312 - 5315 (2015)
The first examples of an organocatalytic Michael addition of a ketone to in situ generated α-nitrostyrenes are reported. A suitably functionalized γ-nitroketone obtained from the organocatalyzed Michael addition was converted into (+)-2-epi-lasubine II, the immediate synthetic precursor of (+)-lasubine II and (-)-subcosine II (enantiomers of the natural quinolizidine alkaloids). Two of the three stereocenters in (+)-2-epi-lasubine II are set by the Michael reaction.
Studies on the synthesis of the lasubine alkaloids
Mohamed Aslam, Nur Filza bte,Simon, Oliver,Bates, Roderick W.
, p. 5032 - 5039 (2018/07/21)
Formal syntheses of lasubine II and subcosine II have been completed by the synthesis of epi-lasubine II. The synthesis involves diastereoselective allylation of a methoxy isoxazolidine and a tandem hydrogenation process leading stereoselectively to a tri
Synthesis of β-Amino-Substituted Enones by Addition of Substituted Methyl Enones to Sulfinimines: Application to the Total Synthesis of Alkaloids (+)-Lasubine II and (+)-241D and the Formal Total Synthesis of (-)-Lasubine i
Reddy, Arava Amaranadha,Reddy, Polimera Obula,Prasad, Kavirayani R.
, p. 11363 - 11371 (2016/11/29)
Addition of silyl enol ethers obtained from substituted methyl enones to chiral sulfinimines afforded the β-amino-substituted enones with excellent selectivity. Utility of the obtained N-sulfinyl β-amino ketones possessing α,β-unsaturation is exemplified
An enantioselective organocatalytic approach to both enantiomers of lasubine II
Verkade, Jorge M.M.,Van Der Pijl, Ferdi,Willems, Marian M.J.H.P.,Quaedflieg, Peter J.L.M.,Van Delft, Floris L.,Rutjes, Floris P.J.T.
supporting information; experimental part, p. 3207 - 3210 (2009/08/08)
A concise stereoselective route providing access to both enantiomers of the bioactive quinolizidine alkaloid lasubine II has been developed. The enantioselectivity was introduced by taking advantage of a proline-catalyzed asymmetric Mannich reaction. Next, the bicyclic system was constructed via a diastereoselective Mannich cyclization and subsequent ring-closing metathesis as the key steps.
Enantioselective rhodium-catalyzed [2+2+2] cycloaddition of alkenyl isocyanates and terminal alkynes: Application to the total synthesis of (+)-lasubine II
Yu, Robert T.,Rovis, Tomislav
, p. 12370 - 12371 (2007/10/03)
The use of TADDOL-based phosphoramidite ligands on rhodium allows for the incorporation of terminal alkynes in the [2+2+2] cycloaddition with alkenyl isocyanates. Terminal aliphatic alkynes provide bicyclic lactams, while the use of aryl alkynes provides complementary access to vinylogous amides. Product selectivity seems to be governed by a combination of electronics and sterics, with smaller and/or more electron-deficient substituents favoring lactam formation. The use of homologous alkenyl isocyanates leads to an expedient asymmetric total synthesis of the alkaloid lasubine II. Copyright
