98%
921
2 minutes
20
We report an unprecedented domino polycyclization from readily available 2,4-dienals and cyclic α,β-unsaturated imines that is initiated by an iso-Nazarov reaction. This Brønsted acid promoted reaction enables the concomitant formation of four bonds, three cycles, and four contiguous stereogenic centers to yield elaborated structures in a single operation. A range of fused hexacyclic molecules is obtained in a highly diastereoselective manner.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/anie.201903860 | DOI Listing |
J Org Chem
September 2025
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), and Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan 410081,
We herein report a palladium-catalyzed dearomative Heck/C(sp)-H activation/[4 + 2] decarboxylative cyclization of C2-tethered indoles. In this transformation, the alkylpalladium(II) species generated by indole dearomatization undergoes C-H activation to form ,-palladacycles, which are subsequently trapped by -bromobenzoic acids or cyclic β-bromoacrylic acids, enabling regio- and diastereoselective construction of hexacyclic and octocyclic fused indolines with a broad substrate scope.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Department of Organic Chemistry, Indian Institute of Science, Bangalore-560012, India.
The unique architecture of naturally occurring ladderane phospholipids has inspired innovation in strategies for their chemical synthesis and biosynthetic hypotheses. Despite the emergence of a few independent synthetic routes to both their known components, i.e.
View Article and Find Full Text PDFOrg Lett
August 2025
Huazhong University of Science and Technology, Tongji Medical College, School of Pharmacy, Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, Wuhan 430030, People's Republic of China.
Asperustins K-P (-), six unreported chlorinated austocystins, were isolated from NRRL 5856. Their structures, including absolute configurations, were elucidated by extensive spectroscopic analyses, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction. Asperustin K () features an unprecedented carbon skeleton with a 6/6/6/5/5/6/6/6 fused octacyclic ring system, while asperustin L () represents a distinctive carbon skeleton with a 6/6/6/5/5/5 hexacyclic ring system.
View Article and Find Full Text PDFOrg Lett
July 2025
State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China.
Daphenylline, a structurally intricate alkaloid, poses a formidable synthetic challenge due to its highly fused hexacyclic [6.6.5.
View Article and Find Full Text PDFOrg Lett
June 2025
School of Chemistry and Chemical Engineering, Nanchang University, Nanchang 330031, P. R. China.
A Pd-catalyzed Sonogashira coupling of iodoalkynones with propargylic ethers bearing indole-tethered unactivated alkenes, followed by an Alder-ene reaction and a Diels-Alder cycloaddition, provides access to various hexacyclic heterocycles containing a dihydropyrido[1,2-]indole scaffold. When similar -propargylic allylic ethers were applied to the reaction, polycyclic compounds containing pyrido[1,2-]indole scaffolds could be obtained after treatment of the fused cyclic products with trifluoroacetic acid. The method features a broad substrate scope, high stereoselectivity, and mild reaction conditions.
View Article and Find Full Text PDF