Lewis Acid Activation of Fragment-Coupling Reactions of Tertiary Carbon Radicals Promoted by Visible-Light Irradiation of EDA Complexes
作者:Spencer P. Pitre、Tyler K. Allred、Larry E. Overman
DOI:10.1021/acs.orglett.1c00023
日期:2021.2.5
The addition of tertiary carbon radicals generated from N-(acyloxy)phthalimide esters to cyclic α,β-unsaturated ketones and lactones is markedly enhanced by the addition of substoichiometric amounts of a Ln(OTf)3. The reaction is accomplished by irradiation with visible light in the absence of a photosensitizer and is suggested to proceed by excitation of a ternary electron donor–acceptor complex between
Novel Rearrangements of Sesquiterpenoid Panasinsane Derivatives under Acidic Conditions
作者:Carlos F. D. Amigo、Isidro G. Collado、James R. Hanson、Rosario Hernández-Galán、Peter B. Hitchcock、Antonio J. Macías-Sánchez、Daniel J. Mobbs
DOI:10.1021/jo0155557
日期:2001.6.1
oxide (7). The novel rearrangement reactions of compounds 11 and 14 under TCNE-catalyzed solvolysis conditions and the reactions of compounds 15 and 16 under superacid conditions (HSO3F/Et2O, -63 degrees C) have been investigated. The ginsenol derivative 17 is obtained from compounds 11 and 14 under TCNE-catalyzed conditions. The rearrangement of compounds 15 and 16 under superacid conditions leads to
Biotransformation of Caryophyllene Oxide by <i>Botrytis cinerea</i>
作者:Rosa Duran、Elena Corrales、Rosario Hernández-Galán、Isidro G. Collado
DOI:10.1021/np980104b
日期:1999.1.1
Biotransformation of caryophyllene oxide (1) with B. cinerea afforded 15 products (2-16). Ten of these (3-5, 7, 9-11, and 14-16) are reported here for the first time. The main reaction paths involved stereoselective epoxidation at C-8/C-13 and hydroxylation at C-7. A rearranged compound was found, which was a cyclization product 16 possessing the caryolane skeleton.
Total Synthesis and Computational Investigations of Sesquiterpene-Tropolones Ameliorate Stereochemical Inconsistencies and Resolve an Ambiguous Biosynthetic Relationship
作者:Christopher Y. Bemis、Chad N. Ungarean、Alexander S. Shved、Cooper S. Jamieson、Taehwan Hwang、Ken S. Lee、K. N. Houk、David Sarlah
DOI:10.1021/jacs.1c02150
日期:2021.4.21
approach to a series of sesquiterpene mono- and bistropolones, including (−)-epolone B, (+)-isoepolone B, (±)-dehydroxypycnidione, and (−)-10-epi-pycnidione. Alongside the development of a general strategy to access this unique family of metabolites were computational modeling studies that justified the diastereoselectivity observed during key cycloadditions. Ultimately, these studies prompted stereochemical
Four-Step Access to the Sesquiterpene Natural Product Presilphiperfolan-1β-ol and Unnatural Derivatives via Supramolecular Catalysis
作者:Leonidas-Dimitrios Syntrivanis、Ivana Némethová、Dario Schmid、Shani Levi、Alessandro Prescimone、Fabian Bissegger、Dan T. Major、Konrad Tiefenbacher
DOI:10.1021/jacs.0c01464
日期:2020.3.25
su-pramolecular resorcinarene capsule as catalyst for the key step. This syntheticapproach also allows access to unnatural derivatives of the natural product, which would not be acces-sible through the biosynthetic machinery. Additionally, this study provides useful insight into the biosynthesis of the presilphiperfolanol natural products, including the first ex-perimental evidence consistent with the