Synthesis of (±)-aklavinone and (±)-auramycinone via electron-deficient o-quinonoid pyrones
摘要:
Dehydration of the formyl acid 3 (R = H) with acetic anhydride in benzene at 80 degrees C generates the quinonoid pyrone 4 which can be trapped with norbornadiene, N-phenylmaleimide and enol silyl ethers; the adduct 6 (R = Me, P = TES) and its 9-epimer 10 from 2-(triethylsilyloxy)propene are readily transformed into (+/-)-auramycinone 2 (R = Me) whilst those [6 (R =vinyl, P = TES) and its 9-epimer] from 2(triethylsilyloxy)buta- 1,3-diene are readily converted into the methyl ethers 24, 25, 33 and 34 of which 24, 33 and 34 are known to be readily converted into (+/-)-aklavinone 2 (R = Et).
Concise Formal Synthesis of the Pseudopterosins via Anionic Oxy-Cope/Transannular Michael Addition Cascade
作者:Vincenzo Ramella、Philipp C. Roosen、Christopher D. Vanderwal
DOI:10.1021/acs.orglett.0c00486
日期:2020.4.17
An anionic oxy-Cope/transannular Michaeladdition cascade converts a spirocyclic architecture-readily available by Diels-Alder cycloaddition-into the hydrophenalene carbon skeleton of the pseudopterosin aglycones. Oxidation of the resulting cyclohexenone ring to the phenol that is characteristic of the targets completes a short formal synthesis.
A tandem Diels–Alder/Mannich approach to the synthesis of AE and ABE ring analogues of Delphinium alkaloids
作者:Kirsten J. Goodall、Margaret A. Brimble、David Barker
DOI:10.1016/j.tet.2012.05.037
日期:2012.7
The one-pot TiCl4 catalysed Diels–Alder/Mannich reaction of α-cyanoaminoacrylates with 2-silyloxy-1,4-butadienes gives 6-keto-3-azabicyclo[3.3.1]nonane-1-carboxylates. Reduction of the ketone and alkylation of the resultant alcohol gives 6-alkoxy-3-azabicyclo[3.3.1]nonanes mimicking the AE rings of a number of Delphinium and Aconitum alkaloids, with the same stereochemistry as the natural products
Diels–Alder reactions of three fused nitrogen-containing bicyclic enones: an efficient method toward novel nitrogen-containing angular tricyclic skeletons
作者:Chi-Min Chau、Kuan-Miao Liu
DOI:10.1039/b806773m
日期:——
The syntheses of three fused bicyclic enones, including 1,2,6,6a-tetrahydro-1-tosyl-cyclopenta[b]pyrrol-3(5H)-one, 1,2,3,6,7,7a-hexahydro-4H-1-tosyl-cyclopenta[b]pyridin-4-one and 1,2,5,6,7,7a-hexahydro-3H-1-tosyl-indol-3-one, via anionic cyclization and Diels-Alder reactions with various dienes to construct novel nitrogen-containing angular tricyclic skeletons are described.
作者:Angie R. Angeles、Stephen P. Waters、Samuel J. Danishefsky
DOI:10.1021/ja8048207
日期:2008.10.15
adhesion inhibitor, peribysin E, has been achieved from carvone. Highlights of the synthesis include a Diels−Alderreaction to generate a cis-decalin framework, followed by semipinacol-type ring contraction to secure the stereochemistry of the C7 quaternary center. Potential mechanistic pathways for the critical ring contraction were studied through deuterium incorporation studies. In addition, an optimized
Synthesis of anthracyclinones via o-quinonoid pyrones
作者:David W. Jones、Christopher J. Lock
DOI:10.1039/c39910001509
日期:——
Dehydration of the acid 3(R = H) with acetic anhydride at 80 °C generates the o-quinonoid pyrone 4 which can be trapped with several alkenes; the adduct 6(R = Me, P = SiEt3) and its 9-epimer from 2-triethylsilyloxypropene are readily transformed into (±)-auramycinone whilst those [(6; R = vinyl, P = SiEt3) and its 9-epimer] from 2-triethylsilyloxybuta-1,3-diene are readily converted into the methyl ethers 12, 13, 14 and 15 of which 12, 14 and 15 are known to be readily converted into (±)-aklavinone.
酸3(R = H)与乙酸酐在80℃下脱水生成邻醌型吡喃酮4,它可以被多种烯烃捕获;加合物 6(R = Me, P = SiEt3) 及其来自 2-三乙基甲硅烷氧基丙烯的 9-差向异构体很容易转化为 (±)-金霉素酮,而那些 [(6; R = 乙烯基, P = SiEt3) 及其 9-差向异构体]由2-三乙基甲硅烷氧基丁-1,3-二烯生成的产物很容易转化为甲基醚12、13、14和15,其中已知12、14和15很容易转化为(±)-aklavinone。