Diversity Oriented Microwave-Assisted Synthesis of (−)-Steganacin Aza-Analogues

Abstract

A novel microwave-assisted, highly efficient protocol for the synthesis of hitherto unknown aza-analogues of (-)-Steganacin, a naturally occurring bisbenzocyclooctadiene lignan lactone with potent antileukemic and tubulin polymerization inhibitory activity, has been developed. Focused microwave irradiation is demonstrated to be highly beneficial in promoting the three crucial steps of the sequence to effect the final ring closure: the Suzuki-Miyaura reaction, Cu-mediated A3-coupling, as well as the intramolecular Huisgen 1,3-dipolar cycloaddition.

Efficient Microwave‐Assisted Synthesis of Secondary Alkylpropargylamines by Using A3‐Coupling with Primary Aliphatic Amines

“…To expand the scope of the protocol, a variety of aliphatic aldehydes were also evaluated. The reactions proceeded smoothly, delivering the corresponding propA C H T U N G T R E N N U N G argylA C H T U N G T R E N N U N G amines in 64-86 % yields ( Table 2, entries [18][19][20][21][22][23][24][25][26].…”

Suzuki–Miyaura Reactions of Halospirooxindole Derivatives

“…[20] Monosubstituted 5Ј-(het)aryl-1-pentyl-2H-spiro[furo- [2,3-b]pyridine-3,3Ј-indolin]-2Ј-ones 4-12 were obtained in good to excellent yields (75-97 %) after purification by column chromatography (Table 1). All reactions required (hetero)arylboronic acid (1.2 equiv.…”

Recent advances in application of intramolecular Suzuki cross-coupling in cyclization and heterocyclization

“…The Suzuki-Miyaura cross-couplings of the silyl ethers 100a and 100b with 2-formylphenylboronic acid and 2-formyl-4-methoxyphenylboronic acid were carried out by Mont and co-workers [37] under microwave irradiation conditions with dioxane/isopropanol (2:1) to afford the corresponding biaryl intermediates 101a-101c in yields of 77, 80, and 82 %, respectively (Scheme 22). That was a key step for the synthesis of hitherto unknown aza-analogues of (-)-steganacin (103), which displays high biological activity.…”