The first synthesis of the natural product (+)-mutisianthol was accomplished in 11 steps and in 21% overall yield from 2-methylanisole. The synthesis of its enantiomer was also performed in a similar overall yield. The absolute configuration of the sesquiterpene (+)-mutisianthol was assigned as (1S,3R). Key steps in the route are the asymmetric hydrogenation of a nonfunctionalized olefin using chiral iridium catalysts and the ring contraction of 1,2-dihydronaphthalenes using thallium(III) or iodine(III). The target molecules show moderate activity against the human tumor cell lines SF-295, HCT-8, and MDA-MB-435.
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http://dx.doi.org/10.1021/jo9000405 | DOI Listing |
J Nat Prod
January 2025
Marbio, Norwegian College of Fishery Science (NFH), Faculty of Biosciences, Fisheries, and Economics, UiT-The Arctic University of Norway, Tromsø 9037, Norway.
J Nat Prod
January 2025
Department of Natural Medicinal Chemistry and Pharmacognosy, School of Pharmacy, Qingdao University, Qingdao 266071, People's Republic of China.
A bioassay-guided chemical investigation of the endophytic fungus F5 resulted in the discovery of two novel sesquiterpenes, chamilactones A and B ( and ), with a new 9,10-seco-15--isoilludalane carbon skeleton, together with several biosynthetically related precursors (-). Their structures and absolute configurations were elucidated by the analysis of MS, NMR, calculated C chemical shifts, ECD calculations, and single-crystal X-ray diffraction data. It was proposed that an unprecedented carbon-carbon bond cleavage between C-9 and C-10 in - was the key step in the biosynthetic pathway of and .
View Article and Find Full Text PDFPhytochemistry
January 2025
Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, People's Republic of China; Laboratory for Marine Drugs and Bioproducts, Qingdao Marine Science and Technology Center, Qingdao, 266237, People's Republic of China. Electronic address:
Two undescribed rearranged diterpenoids, lobopaucinoids A and B (1 and 2), along with thirteen undescribed lobane-type diterpenoids lobopaucinoids C-O (3-15) including a C (11) and two C (12 and 13) undescribed norditerpenoids, were isolated from the soft coral Lobophytum pauciflorum Ehrenberg (Sarcophytidae family) collected from Xisha Islands of the South China Sea. Additionally, two undescribed prenyleudesmane-type diterpenoids, lobopaucinoids P and Q (16 and 17), as well as two known lobane diterpenoids (18 and 19), were also obtained. Their structures were elucidated based on comprehensive spectroscopic data, Mosher's method, Mo(OAc) or Rh(OCOCF)-induced circular dichroism experiment, quantum chemical calculations, and single-crystal X-ray diffraction and literature comparison.
View Article and Find Full Text PDFFood Chem
January 2025
State Key Laboratory of Agricultural Products Safety/ Key Laboratory of Detection for Pesticide Residues and Control of Zhejiang, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, PR China; Agricultural Ministry Key Laboratory for Pesticide Residue Detection, Hangzhou 310021, PR China. Electronic address:
Ethiprole is a second-generation phenylpyrazole insecticide used in agricultural production as an alternative to fipronil due to its lower toxicity to bees. Ethiprole amide is chiral metabolite of ethiprole, but information regarding its formation and degradation in vegetables is limited. Here, the absolute configuration of ethiprole amide enantiomer was determined through circular dichroism, and the behaviors of chiral ethiprole and its metabolites in five kinds of vegetables were studied through field experiments.
View Article and Find Full Text PDFJ Nat Prod
January 2025
Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States.
A structurally novel metabolite, fatuamide A (), was discovered from a laboratory cultured strain of the marine cyanobacterium sp., collected from Faga'itua Bay, American Samoa. A bioassay-guided approach using NCI-H460 human lung cancer cells directed the isolation of fatuamide A, which was obtained from the most cytotoxic fraction.
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