Enantiospecific synthesis of the natural enantiomer of the marine sesquiterpene (-)-4-thiocyanatoneopupukeanane (6) is described. The bicyclo[2.2.2]octanecarboxylate 14, obtained from (R)-carvone via Michael-Michael reaction, was transformed into neopupukeananedione 12 by employing rhodium acetate catalyzed intramolecular C-H insertion of the diazo ketones 16 or 19 as the key reaction. Regioselective deoxygenation of the C-2 ketone transformed the dione 12 into neopupukean-4-one 10. Alternately, the keto ester 18 was also transformed into neopupukean-4-one 10 via regioselective deoxygenation of the ketone in 18 followed by intramolecular rhodium carbenoid C-H insertion of the diazo ketone 31. Finally, neopupukean-4-one 10 was transformed into (-)-4-thiocyanatoneopupukeanane 6 via the alcohol 32 and the mesylate 33.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/jo0102765 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Long-term safety of lentiviral or gammaretroviral gene-modified T cell therapies.
Nat Med
January 2025
Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Long-term risks of gene therapy are not fully understood. In this study, we evaluated safety outcomes in 783 patients over more than 2,200 total patient-years of observation from 38 T cell therapy trials. The trials employed integrating gammaretroviral or lentiviral vectors to deliver engineered receptors to target HIV-1 infection or cancer.
View Article and Find Full Text PDFOxygen, light, and mechanical force mediated radical polymerization toward precision polymer synthesis.
Chem Commun (Camb)
January 2025
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200438, China.
The synthesis of polymers with well-defined composition, architecture, and functionality has long been a focal area of research in the field of polymer chemistry. The advancement of controlled radical polymerization (CRP) has facilitated the synthesis of precise polymers, which are endowed with new properties and functionalities, thereby exhibiting a wide range of applications. However, radical polymerization faces several challenges, such as oxygen intolerance, and common thermal initiation methods may lead to side reactions and depolymerization.
View Article and Find Full Text PDFTransferrin-binding domain inserted-adenovirus hexon engineering enables systemic immune evasion and intratumoral T-cell activation.
Theranostics
January 2025
Department of Pharmacology, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea.
Adenovirus-based therapies have encountered significant challenges due to host immunity, particularly from pre-existing antibodies. Many trials have struggled to evade antibody response; however, the efficiency of these efforts was limited by the diversity of antibody Fv-region recognizing multiple amino acid sequences. In this study, we developed an antibody-evading adenovirus vector by encoding a plasma-rich protein transferrin-binding domain.
View Article and Find Full Text PDFUnderstanding the Reactivity of "Naked" Acyclic Carbene-like Species Featuring a Group 13 Element in the [4+1] Cycloaddition with Benzene.
Inorg Chem
January 2025
Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan.
The chemical reactivity between benzene and the "naked" acyclic carbene-like (G13X) species, having two bulky N-heterocyclic boryloxy ligands at the Group 13 center, was theoretically assessed using density functional theory computations. Our theoretical studies show that (BX) preferentially undergoes C-H bond insertion with benzene, both kinetically and thermodynamically, whereas the (AlX) analogue favors a reversible [4 + 1] cycloaddition. Conversely, the heavier carbene analogues ((GaX), (InX), and (TlX)) are not expected to engage in a reaction with benzene.
View Article and Find Full Text PDFElucidating Photochemical Conversion Mechanism of PDMS to Silica under Deep UV Light and Ozone.
J Phys Chem Lett
January 2025
School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Photochemistry-based silica formation offers a pathway toward energy-efficient and controlled fabrication processes. While the transformation of poly(dimethylsiloxane) (PDMS) to silica (often referred to as SiO due to incomplete conversion) under deep ultraviolet (DUV) irradiation in the presence of oxygen/ozone has experimentally been validated, the detailed mechanism remains elusive. This study demonstrates the underlying molecular-level mechanism of PDMS-to-silica conversion using density functional theory (DFT) calculations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!