919082-38-5Relevant academic research and scientific papers
Total Synthesis of Lamellarins G, J, L, and Z Using One-Pot Halogen Dance/Negishi Coupling
Mori, Atsunori,Morii, Kazuki,Morikawa, Daiki,Okano, Kentaro,Yasuda, Yuto
, p. 13388 - 13401 (2021/10/12)
A bottom-up synthesis of lamellarins G, J, L, and Z was achieved via one-pot halogen dance/Negishi coupling of a lithiated dibromopyrrole derivative. The easily accessible dibromopyrrole bearing an ester moiety underwent halogen dance smoothly at -78 °C within 10 min. The resultant α-pyrrolyllithium was transmetalated to the corresponding organozinc species, which was then coupled with an aryl iodide in the presence of catalytic palladium to provide the fully substituted pyrrole. Subsequent halogen-lithium exchange was performed to incorporate a boronate group exclusively at the β position proximal to the ester moiety. This synthetic intermediate allowed stepwise diarylation for the total synthesis of lamellarins G, J, L, and Z.
Total synthesis of natural and unnatural lamellarins with saturated and unsaturated D-rings
Ploypradith, Poonsakdi,Petchmanee, Thaninee,Sahakitpichan, Poolsak,Litvinas, Nichole D.,Ruchirawat, Somsak
, p. 9440 - 9448 (2007/10/03)
(Chemical Equation Presented) Twenty-eight natural and unnatural lamellarins with either a saturated or an unsaturated D-ring were synthesized according to our developed synthetic route. The key step involved the Michael addition/ring closure (Mi-RC) of the benzyldihydroisoquinoline and α-nitrocinnamate derivatives, which provided the 2-carboethoxypyrrole intermediates in moderate to good yields (up to 78% yield). Subsequent hydrogenolysis/lactonization furnished lamellarins with a saturated D-ring in excellent yields (up to 93% yield). DDQ oxidation of the saturated lamellarin acetates led directly to the corresponding unsaturated analogues in 54-95% yield. In addition, only two steps in our developed strategy require column chromatography.
