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From a single alkene to two different alkenes! A convenient Fe-catalyzed A–D–A–T-type radical-dual-difunctionalization and cross-coupling of two different alkenes to provide chain elongated and tri...

Spiroinonotsuoxotriols A (1) and B (2), two highly rearranged pentacyclic triterpenoids featuring a novel 7(8 → 9)abeo-21,24-cyclo-lanostane skeleton, together with their proposed precursors 3-5, were isolated from the sclerotia of the white-rot fungus Inonotus obliquus. Their structures including the absolute configurations were elucidated by extensive spectroscopic analyses and single-crystal X-ray diffraction. The biogenetic pathway of 1 and 2 was proposed. Compounds 1 and 2 exhibited potent α-glucosidase inhibitory activity as compared with the positive control acarbose.

A convenient Fe-catalyzed four-component radical dual difunctionalization and ordered assembly of two alkenes with aromatic/aliphatic aldehydes and TBHP to provide chain elongated β,δ-functionalized ketones via a one-pot procedure has been developed. Aldehydes were homolytically cleavaged to produce acyl radicals and subsequently allowed for the successive construction of C(sp2)-C(sp3), C(sp3)-C(sp3), and C(sp3)-O bonds via dual radical insertions and radical-radical coupling, following the intrinsic nucleo/electrophilic reactivity of both the radicals and alkenes.

A convenient Fe-catalyzed four-component radical dual difunctionalization and ordered assembly of two alkenes with aromatic/aliphatic aldehydes and TBHP to provide chain elongated β,δ-functionalized ketones via a one-pot procedure has been developed. Aldehydes were homolytically cleavaged to produce acyl radicals and subsequently allowed for the successive construction of C(sp

Three new ring B-seco limonoids, ciliatonoids A-C (1-3), were isolated from Toona ciliate and structurally characterized by spectroscopic data, X-ray crystallography, and electronic circular dichroism analysis. Ciliatonoids A and B feature an unprecedented limonoid architecture, while ciliatonoid C belongs to a rare class of limonoids. Biological evaluation showed that compound 3 exhibited modest activities against the tested tumor cell lines.

Duclauxamide A1 (1), a new polyketide-derived heptacyclic oligophenalenone dimer with a N-2-hydroxyethyl moiety, was isolated from Penicillium manginii YIM PH30375. Spectroscopic analysis, X-ray single crystal diffraction, and (13)C NMR DFT calculations confirmed that compound 1 and other duclauxin analogues possess the unified S configuration at C-9', which corrects a long-standing misrepresentation of duclauxins as C-9'R epimers. A plausible biosynthetic pathway for duclauxins is proposed on the basis of previous acetate labeling results for duclauxin and sclerodin.

Three limonoids, trichiconin A (1) possessing a new carbon skeleton of a rearranged A,B-ring system and trichiconins B (2) and C (3) featuring an unprecedented A,B,D-seco skeleton, were isolated from the twigs of Trichilia connaroides. The carbon scaffold of trichiconin A is designated as trichiconane. Their structures with absolute stereochemistry were determined by spectroscopic data, X-ray crystallography, and CD analysis. Compounds 2 and 3 showed modest anti-HIV activities.